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Oxygen consumption levels and metabolic rate temperature curves of various lizard species from three different climatic regions were examined in relation to ambient temperature. The species used in this research were as follows: Anguis fragilis, Lacerta vivipara, Lacerta agilis (cool temperate species); Blanus cinereus, Podarcis hispanica, Podarcis lilfordi brauni, Podarcis lilfordi lilfordi, Podarcis muralis, Psammodromus algirus, Tarentola mauritanica (warm temperate species); Chalcides ocellatus, Acanthodactylus opheodurus, Acanthodactylus schmidti (desert species). A double chamber volumetric closed system was used to measure the resting oxygen consumption of the lizards. Acute oxygen consumption determinations were made, that is the lizards were not allowed to acclimate to the test temperatures. Interspecific differences in levels of resting oxygen consumption and in the characteristics of the metabolic rate temperature curves were examined in relation to methods of thermoregulation and in relation to the ecology of the respective species. Evidence for `temperature dependent shifts` and `low thermal dependence` was found in the metabolic rate temperature curves of some species. A diminishing Q10 at or below the voluntary body temperatures suggests some degree of metabolic homeostatsis and energy conservation.

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The composition of the food of Genetta genetta was studied from 17 groups of droppings with more than 2000 remains of animals and an undeterminated number of plants. On the small island of Cabrera lizards form the main diet. On the other islands mammals (Rodentia) and lizards (Lacertidae, Geckonidae) are the most common prey animals, followed by various insects. Plant material has been found more regularly on Ibiza. Genetta certainly is an euryphagous animal, but this behaviour pattern may alter to a stenophagous phase in certain environments.

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Caves are prone to preserve fossils, mainly of vertebrates. On the Balearic Islands the Pliocene and Quaternary vertebrate fossil record allows to study the faunal composition and faunistical turnover on each island. On the Gymnesic Islands Myotragus balearicus was an endemic fossil Caprinae that lived until human arrival. It was the key species to understand the islands` ecology. The terrestrial vertebrate fauna that lived with Myotragus comprised a dormouse and a shrew, as well as an endemic lizard and the ferreret. The Upper Pleistocene and Holocene vertebrate fauna from the Pityusic Islands was only composed by birds, bats, and a lizard species. The absence of terrestrial mammals in this fauna constitutes the greatest faunistical anomaly in the whole Mediterranean.

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In this paper we present a biogeographical analysis of the herpetological biota of the Balearics and Pityusics. Baleaphyne muletensis, Lacerta (Podarcis) lilfordi and Lacerta (Podarcis) pityusensis are considered as palaeoendemics and, plausibly, they colonized our islands during the Messinian. All the remaining species of the present day herpetological biota must have inmigrated to Balearics and Pityusiccs due to the intervention of man.

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Dietary studies are essential to unravel the functioning of ecosystems and ultimately to understand biodiversity. This task, which at first may seem simple, becomes especially complex in those cases of omnivorous species with highly variable diets. In this regard, the emergence of next-generation DNA sequencing methodologies represents a powerful tool to address the problem. Here we implement a high-throughput metabarcoding strategy based on the analysis of four molecular markers aimed at sequencing both mitochondrial (animal prey) and chloroplast (diet plants) genome fragments from fecal samples of two lizard species endemic to the Balearic Archipelago (Podarcis lilfordi and P. pityusensis) obtained through non-invasive methods. The results allowed for the characterization of their diets with a high degree of taxonomic detail and have contributed a large number of new trophic records. The reported diets are based mainly on the consumption of arthropods, mollusks and plants from a diversity of taxonomic orders, as well as carrion and marine subsidies. Our analyses also reveal inter- and intra-specific differences both in terms of seasonality and geographical distribution of the sampled lizard populations. These molecular findings provide new insights into the trophic interactions of these threatened endemic lizards in their unique and isolated ecosystems.

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The diets of insular lizards are extremely varied, depending on the different environmental characteristics of each island population. This is particularly evident in the case of the populations of small coastal islets of the Balearic Islands, where the Balearic lizard, Podarcis lilfordi, is found. The study of trophic ecology carried out by means of traditional tools, such as morphological analysis of feces, has made it possible to detect numerous prey and nutritional elements. However, these methods are clearly insufficient, as some rare groups are not detected. It is also difficult to identify remains of marine subsidies or of foods contributed to these small islands by other predators, such as seabirds. The current study demonstrates the advantages of combining morphological diet analysis with the molecular study of individual feces samples obtained from the same populations. We obtained a greater diversity of prey groups using the combined methodologies, with each method identifying prey items that were not detected using the other method. Particularly, the study of diets at the molecular level identified plant species consumed by lizards that were, occasionally, not identified in morphological analyses. Conversely, the traditional morphological study of an equivalent number of fecal samples allowed for the identification of several prey groups that had not been detected in the molecular study. From this viewpoint, the advantages and disadvantages of each methodology are discussed.

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Gut microbial communities provide essential functions to their hosts and are known to influence both their ecology and evolution. However, our knowledge of these complex associations is still very limited in reptiles. Here we report the 16S rRNA gene faecal microbiota profiles of two lizard species endemic to the Balearic archipelago (Podarcis lilfordi and P. pityusensis), encompassing their allopatric range of distribution through a noninvasive sampling, as an alternative to previ- ous studies that implied killing specimens of these IUCN endangered and near-threatened species, respectively. Both lizard species showed a faecal microbiome composition consistent with their omnivorous trophic ecology, with a high representa- tion of cellulolytic bacteria taxa. We also identified species-specific core microbiota signatures and retrieved lizard species, islet ascription, and seasonality as the main factors in explaining bacterial community composition. The different Balearic Podarcis populations are characterised by harbouring a high proportion of unique bacterial taxa, thus reinforcing their view as unique and divergent evolutionary entities.

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Vorarbeiten über Schädlingsfauna der Kriehtieren (Reptilien) in der Türkei -- Die Kriehtiere leben meistens auf dem Lande. Viele sind Insektenfresser. Zahlreiche Arten nehmen tierische und pflanzliche, oder ausschliesslich pflanzliche Nahrung zu sich. Ihre wirtschaftliche Schäden an Kulturpflanzen sind gelegentlich. Die besonderen Arten von Pflanzenschädlingen, die in der Türkei leben, sind noch nicht genugend untersucht. Darüber findet man heute sehr wenige und nur zerstreute Veröffentlichungen und Beobachtungen in der Hand. In dieser Vorarbeit sind die bisheute bekannten pflanzenschädliche Arten von Kriehtieren bzw. Eidechsen und Schildkröten, in ihren Verbreitungsgebieten und ihre Nährpflanzen zum erstenmale zusammengestellt. Selbstverstândlioh sind darüber weitere und vertiefte Beobachtungen erforderlich. -- Die Arten der Eidechsen: Agama stellio L. (Schleuderschwanz). Verbreitung: Anatolien, Ankara (Ebner 1919, Kerville 1939). Nährpflanzen: Die süssen Früchten wie Feigen, Pfirsiche, Zuckermelonen, und andere Früohte, Salate, Lattichsalate.,- Agama stellio stellio L. Verbreitung: Süd - und west Türkei, Amasya, Nigde, Diyarbakir, Kayseri, Çanakkale (Bodenheimer 1946 und andere). Nährpflanzen: Wie bei Agama stellio L. -- Agama ruderata Oliv. (Ankara, Kerville 1939), Agama ruderata ruderata Oliv. Ankara, Eregli (Konya), Mardin, Nusaybin, Gaziantep und Malatya (Bodenheimer 1946), Eine Probe in Eregli (Konya) wurde vom Verfasser gefunden. Nährpflanzen: Noch nicht festgestellt, vielleicht wie bei Agama stellio L. -- Lacerta viridis Laur. var. major D. und B. (Srnaragdeidechse). Verbreitung: Westanatolien, andere Fundorte sind nicht bekannt. Nährpflanzen: Weintrauben, Feigen, Kirchen und andere süsse Früchten. Note: Noch mehrere Lacerta Arten wurden in der Türkei gefunden, ob sie pflanzliche Nahrung zu sich nehmen oder nicht, ist unklar. -- Die Arten der Schildkröten. Testudo graeca L. (Grichische Schildkröte). Verbreitung: Fast in allen Geblieten der Türkei. Nährpflanzen: Steppenpflanzen, junges Getreide - Baumwolle -Luzerne - Pflanzen, Gemüsen, Weintrauben, Blätter und Juruge Triebe von vielen jungen Pflanzen. -- Emys orbicularis L. (Surnpf-oder Europäische Schildkröte). Verbreuitung: Ankara (Kerville 1939), Manisa, Bursa, Kayseri, Eski¬sehir, Adapazari, Turhal (Bodenheimer 1946 und andere). Nährpflanzen: Wedntrauben, Zucker-und Wassermelonen. - Note: Noch andere Arten der Schâldknöten leben auch in der Türkei, aber ihre Nahrung ist nicht bekannt.

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The sensory innervation of the pineal organ of adult Lacerta viridis has been investigated. Some specimens of Lacerta muralis lillfordi were also used. In the pineal epithelium, a small number of nerve cell pericarya of a sensory type are present. They lie either solitary or in small clusters close to the basement membrane. The axons originating from the nerve cell bodies, i. e. the pineal sensory nerve fibers, first course in the intraepithelial nerve fiber layer which is only locally present and contains a restricted number of unmyelinated fibers. In Lacerta viridis, the pineal fibers generally leave the epithelium at the proximal part of the organ proper. They then form small bundles which run along the outer surface of the basement membrane in the leptomeningeal connective tissue covering. At the proximal end of the pineal stalk the single bundles assemble constituting the pineal nerve. In Lacerta muralis the fibers leave the pineal epithelium at the proximal end of the stalk running farther down within the epithelium. Many fibers become myelinated after leaving the pineal epithelium. The pineal nerve runs ventralward in the midplane just caudal to the habenular commissure to which no fibers are given off. Continuing their ventralward course between the habenular commissure and the rostral end of the posterior commissure which is traversed by some of them, the pineal fibers reach the dorsal border of the subcommissural organ. Small separate aberrant pineal bundles traverse the posterior commissure at various more caudal levels. Having reached the dorsal border of the subcommissural organ, part of the pineal fibers continue their ventralward course directly running along the lateral sides of this organ to reach the periventricular nerve fiber layer lateral and ventral to it. A restricted number of fibers first turns in a caudal direction running between the base of the posterior commissure and the base of the subcommissural organ before turning ventralward to reach the periventricular layer. Most probably, pineal fibers do neither join the posterior commissural system nor innervate the subcommissural organ. Once having reached the periventricular layer, some pineal fibers curve in a rostral direction while others, before doing so, send a collateral in a caudal direction. Both, the main fibers and the collaterals, contribute to the formation of the periventricular layer. The sites of termination of the pineal fibers could not be ascertained. From the presence of intraepithelial sensory nerve cell bodies and from literature data on the ultrastructure of pineal neurosensory cells it is concluded that the adult pineal organ of Lacerta has a, although rudimentary, (photo)sensory function. The demonstration by our guest-worker Dr. W. B. Quay, of the intraepithelial presence of a tryptamine compound, probably serotonin, points, moreover, to a secretory function of this organ. In adult Lacerta a well-developed parietal nerve connects the parietal eye with the left lateral habenular nucleus. It traverses the habenular commissure.

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Algyroides fitzingeri, Algyroides marchi, Algyroides moreoticus, Algyroides nigropunctatus, Lacerta agilis, Lacerta lepida, Lacerta princeps, Lacerta schreiberi, Lacerta strigata, Lacerta trilineata, Lacerta viridis, Lacerta andreanszkyi, Lacerta armeniaca, Lacerta bedriagae, Lacerta brandtii, Lacerta cappadocica, Lacerta caucasica, Lacerta chlorogaster, Lacerta cyanura, Lacerta danfordi, Lacerta derjugini, Lacerta dugesii, Lacerta fraasii, Lacerta graeca, Lacerta horvathi, Lacerta jayakari, Lacerta laevis, Lacerta monticola, Lacerta mosorensis, Lacerta oxycephala, Lacerta parva, Lacerta perspicillata, Lacerta praticola, Lacerta rudis, Lacerta saxicola, Lacerta vivipara, Gallotia atlantica, Gallotia galloti, Gallotia simonyi, Podarcis erhardii, Podarcis filfolensis, Podarcis hispanica, Podarcis lilfordi, Podarcis melisellensis, Podarcis milensis, Podarcis muralis, Podarcis peloponnesiaca, Podarcis pityusensis, Podarcis sicula, Podarcis taurica, Podarcis tiliguerta, Podarcis wagleriana, Psammodromus algirus, Psammodromus blanci, Psammodromus hispanicus, Psammodromus microdactylus.

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The ability to shed (autotomize) all or part of the tail, usually in response to predator attack, and often to subsequently regenerate it is widespread in lizards and amphisbaenians and also occurs in a few snakes and in the tuatara. Most species possess a sophisticated intravertebral autotomy mechanism which seems to be primitive in the Squamata. This appears to have been independently lost in members of many groups, but some agamids and snakes have regained the ability to shed their tails by a simpler intervertebral means and a -number of agamids have also redeveloped tail regeneration as well. Breakable tails are used to evade capture in two main ways: by enabling reptiles to break away from predators that have grasped them by the tail and by providing a distraction which deflects the attention of the attacker away from the vulnerable head and body. It is argued that loss of caudal autotomy has occurred when the costs of tail shedding outweigh its benefits. Likely costs include the expense of regrowing the tail and the loss of a variety of possible tail functions that may cause partial incapacitation, at least until the tail regenerates. Benefits of autotomy are liable to be low if predation is rare, if the animal is able to protect itself effectively in other ways, if it is too slow to evade further pursuit after the tail is shed, or if the tail is small or unpalatable and consequently not likely to distract a predator. Benefit variation may well be greater than cost variation and therefore more important in initiating the loss of autotomy mechanisms. Many taxa that do not shed the tail appear to conform to the above interpretation, but in some cases, such as the Platynota, Agamidae and Chamaeleonidae, lack of intravertebral autotomy may reflect the history of these groups rather than being a direct result of present ecological pressures. The distribution of intervertebral autotomy in the Agamidae suggests that it may have evolved only in rather special circumstances where tail fragility is advantageous even in the absence of the ability to regenerate. Restriction ot autotomy planes to the tail-base, so that the whole organ is lost, a condition found in a number of relatively slow-moving geckoes, is interpreted as a means of ensuring that enough of the tail is shed to distract a predator from further pursuit. The stimulus necessary to induce autotomy can vary rapidly in individual lizards and at least some of these changes probably maximize the effectiveness of the tail-shedding mechanism. Differences in the readiness with which all or part of the tail is shed exist between species and are likely to reflect the balance of costs and benefits in particular cases. Variations in incidence of broken tails between species and populations may be due to such differences in fragility but many other factors may play a part, including the age structure of samples, incidence of unsuccessful attacks by predators and ability to evade predators after autotomy. There is a clear tendency for climbing lizards, especially those living on rock surfaces, to have higher incidences of broken tails than ground-dwelling species, perhaps because the tail is usually less important in locomotion in the first group. Many lizards possess conspicuously coloured tails and tail movements that seem likely to help distract attention from the head and body. Conspicuous tail colouring is more frequent and often better developed in young animals, which tend to be more vulnerable than adults, and in active species from open habitats where crypsis may not always be very effective. Conspicuous tails usually have contrasting light and dark areas in nocturnal forms but are often a single bright colour in diurnal ones, probably reflecting the visual capacities of their respective predators. The predominance of blue tails in day-active species may be because this colour is striking close to but not very arresting at a distance, so it may not attract predators from far away while still drawing their attention at close quarters.

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Twenty-four species of lacertid lizards were examined at 31 sites in western Yogoslavia, Greece and Iberia. Comparative observations were made on over 4500 individual lizards, noting such features as times of activitiy, hunting methods, diet, micro- and macrohabitat, refuges used and body temperature. These data are used as a basis for assessing resource partition in related sympatric species, for find out whether different systematic groups have characteristic types of niche, and for comparing cumminity structures in the peninsulas of southern Europa. Acanthodactylus erythrurus, Algyroides marchi, Algyroides moreoticus, Algyroides nigropunctatus, Lacerta agilis, Lacerta graeca, Lacerta horvathi, Lacerta lepida, Lacerta monticola, Lacerta oxycephala, Lacerta mosorensis, Lacerta schreiberi, Lacerta trilineata, Lacerta viridis, Lacerta vivipara, Podarcis bocagei, Podarcis erhardii, Podarcis hispanica, Podarcis melisellensis, Podarcis milensis, Podarcis muralis, Podarcis peloponnesiaca, Podarcis sicula, Podarcis taurica, Psammodromus algirus, Psammodromus hispanicus.

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The Lacertidae appear to be most closely related to the worm lizards (Amphisbaenia) and then the Teiodea. Living forms fall into four main units, a basal Gallotiinae, and the Lacertinae, Tykadromus, and Eremiainae. Relationships among these and available fossils suggest lacertids arose in Europe, where they have been present for at least 50Myr and then spread independently to East Asia (Takydromus) and the Afrotropical region (Eremiainae). The ancestors of living species probably had a broad structural niche involving some climbing ability in mesic situations. There were later multiple shifts to ground-dwelliung and specialised climbing on open surfaces and in vegetation matrixes, and to xeric habitats. Gallotiinae includes the west Mediterranean Psammodromus and the Canary Island Gallotia which has produced an adaptive radiation in this archipelago including giant and herbivorous species. The Lacertinae occur mainly in Europe and mesic areas nearby. They appear to have initially spread in the Miocene and speciated rapidly to produce many largely allopatric units that are assigned to Lacerta s. lat. All except L. (Darevskia) of the Caucasus and neighbouring regions have relatively few present species. Three of four units have spread more widely including L. (Lacerta), L. (Timon), Algyroides and Podarcis. These have distinctive ecological features that enable them to coexist with the other forms. Podarcis may have been responsible for the restriction of some small-bodied Lacerta s. lat. And Algyroides to small distributions in specialised habitats. Surviving members of Takydromus probably speciated in the late Miocene. They primitively have many derived morphological and behavioural features functionally associated with climbing in vegetation matrixes but some lineages have become secondarily ground-dwelling. A DNA-based phylogeny shows the group has many anatomical parallelisms and reversals. The Eremiainae are characterised by a distinctive ulnar nerve pattern and hemipenis structure. The group intially spread into mesic habitats in the Afrotropical region. Forms concerned are Omanosaura (E. Arabia), Australolacerta (S. Africa), the Equatorial group (central Africa), Poromera (W. Africa) and Tropidosaura (S. Africa). The Equatrorial African group includes Adolfus, Gastropholis and Holaspis, the latter having many derived features functionally associated with gliding and others that are exaptations to this activity. One clade derived from mesic Eremiainae shifted into xerioc ground niches and developed many adaptations to these. Within this units, Latastia, Phiolochortus, Heliobolus and Pseuderemias may form a clade centred on northeast Africa, while Ichnotropis, its sister Meroles, and Pedioplanis occur in the south of the continent. One large clade invaded Asia giving rise to Eremias, Ophisops, Acanthodactylus and Mesalina, the last three of which later colonised dry areas of North Africa, sometimes on more than one occasion. There are several series of ecomorphs in the Lacertidae, each of which has developed between 2 and 8 times, although sometimes to varying extents. They involve adaptations to dense vegetation on the ground, climbing in vegetation matrixes, forest environments, large size, rocky situations, and Aeolian sand. Lineage history and character lability have both been important in determining how lacertids have adapted. The relatively limited ecological and morphological diversity in the group is likely to have been due to restricted opportunity rather than limited ability to evolve.

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DNA sequence indicates the Lacertidae contain two subfamilies, Gallotiinae and Lacertinae, the latter comprising two monophyletic tribes, the Eremiadini of Africa and arid southwest and central Asia, and the Lacertini of Europe, northwest Africa and southwest and east Asia. Relationships within the 108 species of Lacertini are explored using mtDNA (291 bp cytochrome b; 329 bp 12S rRNA for 59 nominal species, and reanalysis of the data of Harris et al. 1998, and Fu 2000). The morphology of the tribe is reviewed and 64 of its characters (equivalent to 83 binary ones) also used to assess relationships. The Lacertini are assigned to 19 monophyletic units of 1 to 27 species, recognised here as the following genera (contents are indicated in brackets): Algyroides, Anatololacerta gen. nov. (L. danfordi group), Apathya (L. cappadocica group), Archaeolacerta (L. bedriagae), Dalmatolacerta gen. nov. (L. oxycephala), Darevskia (L. saxicola group), Dinarolacerta gen. nov. (L. mosorensis), Hellenolacerta gen. nov. (L. graeca), Iberolacerta (L. monticola group), Iranolacerta gen. nov. (L. brandtii and L. zagrosica), Lacerta s. str. (sand and green lizards, L. agilis group), Parvilacerta gen. nov. (L. parva and L. fraasii), Phoenicolacerta gen. nov. (L. laevis group), Podarcis (wall lizards), Scelarcis (L. perspicillata), Takydromus (Asian grass lizards), Teira (L. dugesii), Timon (ocellated lizards, L. lepida group) and Zootoca (L. vivipara). Both mtDNA and morphology indicate that Lacerta and Timon are sister taxa, and DNA suggests further possible relationships among genera (Fig. 1, p. 6). Neither DNA nor morphology indicates that the archaeolacertas (sometimes formalised as Archaeolacerta sens. lat.) form a clade. Instead, they are representatives of an ecomorph associated with living on rock exposures and using the narrow crevices that these contain. The Lacertidae probably arose in the European area, with the Gallotiinae later reaching Northwest Africa and the Canary Islands, and the ancestor of the Eremiadini invading Africa in the mid-Miocene. The Lacertini spread through much of their present European range and diversified, perhaps largely by repeated vicariance, around 12–16 My ago, producing the ancestors of the present mainly small-bodied genera, which then underwent often modest speciation. Three units spread more widely: the Lacerta-Timon clade of large-bodied lizards probably dispersed earliest, followed by Algyroides and then Podarcis. Overall, European Lacertidae show a pattern of repeated spread, often accompanied by restriction of previous groups. Expansion of Lacertini may have displaced earlier lacertid lineages from all or much of Europe; while spread of Podarcis may have restricted many other genera of Lacertini. The earlier expansion of the Lacerta-Timon clade probably did not have this effect, as difference in adult body size restricted competitive interaction with other forms. Several invasions of more distant areas also occurred: of East Asia by Takydromus over 10 My ago, and more recently of northwest Africa by Podarcis, Scelarcis and Timon, and Madeira by Teira. Relationships within the Eremiadini estimated from both mtDNA, and nDNA differ considerably from those based on morphology. They indicate relatively mesic forms may have diversified widely across Africa and given rise to at least three independent invasions of arid habitats. MtDNA also indicates that Lacerta andreanskyi belongs in the Eremiadini and may occupy a basal position there. It is assigned to a further new genus, Atlantolacerta gen. nov.

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The European Union is one of the world`s largest markets for live reptiles, such as snakes, lizards and tortoises, and the exotic and scaly animals have become increasingly fashionable as pets since the early 1990s. Even though captive-breeding efforts have improved significantly in the last few decades, a large proportion of the reptiles offered in pet shops in the EU still originate from the wild and hence the live reptile trade can have a considerable impact on the conservation status of these species.

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The family Lacertidae is today represented by seven genera at Mediterrranean islands: Acanthodactylus, Algeroides, Lacerta (Archeolacerta included), Ophisops, Podarcis, Psammodromus and Timon (if we accept the validity of this taxon). These genera include 32 different species. The fossil record of lacertid lizards at these islands includes 66 citations from Lower Miocene (Lacertidae sp. From Sardinia) to Historic times. In spite of this relatively large amount, the citations are only from two genera, Lacerta (Archeolacerta included) and Podarcis; 8 present day species: Lacerta cf. viridis (=trilineata) from the Lower Pleistocene and the Holocene of Sicily; L.(Archeolecerta) bedriagae, from the Upper Pliocene of Sardiniaand the Middle Pleistocene of Corsica; Podarcis lilfordi (including probably its ancestor) from the Miocene and Pliocene of Mallorca and Minorca; P.erhardii from the Holocene of Crete; Podarcis pityusensis (including probably its ancestor) from the Pliocene of Ibiza; P.sicula from the Holocene of Corsica and P.tiliguerta from the Middle Pleistocene of Corsica and the Upper Pleistocene of Sardinia, as well as two fossil species, L.siculimelitensis from the Pleistocene s.l. of Malta and the Middle and Upper Pleistocene of Sicily and Lacerta n.sp. from the Middle Pleistocene of Corsica. Finally, a summary of different hypotheses regarding the origin of lacertid lizards at Mediterranean islands is given.

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Here we describe a new genus and species of Lacertidae, Maioricalacerta rafelinensis, gen. et sp. nov, a large-sized lizard with amblyodont teeth from the early Pliocene (Zanclean) of Mallorca (Balearic Islands, western Mediterranean Sea). The presence of amblyodont teeth separates Maioricalacerta from recent species of Lacertidae. Maioricalacerta differs from the amblyodont lacertids of the European Tertiary (Quercycerta, Escampcerta, Mediolacerta, Pseudeumeces, Dracaenosaurus, Amblyolacerta, and Ligerosaurus) in the anteroposterior and mediolateral widening of the teeth and in the wide lateral wall of the dentary, which is massive, relatively short, and robust. Dracaenosaurus displays a similar morphology of the dentary, but the number of teeth is lower and they are more amblyodont than in Maioricalacerta. The dentition observed in Maioricalacerta suggests that the diet of the species was related to a consumption of hard prey, perhaps molluscs. The length reduction of the dentary constitutes an evolutionary biomechanical advantage to consume this kind of prey as it improves jaw-closing force. However, its movement is likely to have been slower but potentially more accurate. The robustness of the dental structures in Maioricalacerta also contributes to enhance the resistance of the bone against the increased static pressure to which it is subjected during jaw closure. Maioricalacerta is the most Recent amblyodont lacertid known and the only one described from the Pliocene of Europe.

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Compositional variation of the gut microbiota across host allopatric populations can reflect both adaptation and stochasticity since the time of separation. Major factors shaping this variation include the host phylogeographic and demographic history, the microbiota inheritance, environmental inputs and dispersal of bacteria. Here we explored the impact of these factors in driving gut community diversity in seven allopatric populations of the omnivorous lizard Podarcis lilfordi from the Menorcan coastal islets, all descending from an ancestral mainland population. Using 16S rRNA Illumina sequencing, we showed that ‘islet’ and ‘age’ (time since islet separation from mainland) were the only significant variables in microbial community clustering, suggesting a partial islet-restricted diversification following these lizards phylogeography. Despite a significant variation, islets/populations were characterized by a remarkably low bacterial uniqueness (2.4% of total OTUs) and a minor differential enrichment of taxa, indicating a negligible impact of local inputs and important host common constraints. Overall, the extant pattern of similarity/dissimilarity among islets is compatible with partial retention of the ancestral mainland microbial pool, with differences among islets potentially explained by a differential loss of bacteria following population fragmentation and bottlenecks (i.e. ecological drift). While more quantitative data are needed to validate this hypothesis, this study unveils the importance of considering both neutral and niche-driven processes in driving contemporary patterns of gut metacommunity diversity.

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Background. Integrative studies of animals and associated microbial assemblages (i.e., the holobiont) are rapidly changing our perspectives on organismal ecology and evolution. Insular vertebrates provide ideal natural systems to understand patterns of host-gut microbiota coevolution, the resilience and plasticity these microbial communities over temporal and spatial scales, and ultimately their role in the host ecological adaptation. -- Methods. Here we used the endemic Balearic wall lizard Podarcis lilfordi to dissect the drivers of the microbial diversity within and across host allopatric populations/islets. By focusing on three extensively studied populations/islets of Mallorca (Spain) and fecal sampling from individually identified lizards along two years (both in spring and autumn), we sorted out the effect of islet, sex, life stage, year and season on the microbiota composition. We further related microbiota diversity to host genetics, trophic ecology and expected annual metabolic changes. -- Results. All the three populations showed a remarkable conservation of the major microbial taxonomic profile, while carrying their unique microbial signature at finer level of taxonomic resolution (Amplicon Sequence Variants (ASVs)). Microbiota distances across populations were compatible with both host genetics (based on microsatellites) and trophic niche distances (based on stable isotopes and fecal content). Within populations, a large proportion of ASVs (30–50%) were recurrently found along the four sampling dates. The microbial diversity was strongly marked by seasonality, with no sex effect and a marginal life stage and annual effect. The microbiota showed seasonal fluctuations along the two sampled years, primarily due to changes in the relative abundances of fermentative bacteria (mostly families Lachnospiraceae and Ruminococcaceae), without any major compositional turnover. -- Conclusions. These results support a large resilience of the major compositional aspects of the P. lilfordi gut microbiota over the short-term evolutionary divergence of their host allopatric populations (<10,000 years), but also indicate an undergoing process of parallel diversification of the both host and associated gut microbes. Predictable seasonal dynamics in microbiota diversity suggests a role of microbiota plasticity in the lizards’ metabolic adaptation to their resource-constrained insular environments. Overall, our study supports the need for longitudinal and integrative studies of host and associated microbes in natural systems.

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Es gibt sicherlich verschiedene Möglichkeiten, im Terrarium gehaltene Eidechsen zu überwintern. Der eine schwört auf seinen Keller, der andere auf eine laubgefüllte Grube in seinem Garten. Nun, wem beides nicht zur Verfügung steht, dem kann auch ein Kühlschrank ganz ausgezeichnete Dienste leisten. Freilich ist nicht gemeint, die Eidechsen frei zwischen Wurst und Käse zu betten, vielmehr bedarf es einiger Vorbereitungen. Im wesentlichen stellen sich zur Überwinterung von Eidechsen 4 Fragen: 1. wen? 2. wann? 3. wie? Und 4. wie lange? Auf diese 4 Fragen soll im in diesem Bericht eine Antwort gegeben werden.

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Es gibt sicherlich verschiedene Möglichkeiten, im Terrarium gehaltene Eidechsen zu überwintern. Der eine schwört auf seinen Keller, der andere auf eine laubgefüllte Grube in seinem Garten. Nun, wem beides nicht zur Verfügung steht, dem kann auch ein Kühlschrank ganz ausgezeichnete Dienste leisten. Freilich ist nicht gemeint, die Eidechsen frei zwischen Wurst und Käse zu betten, vielmehr bedarf es einiger Vorbereitungen. Im wesentlichen stellen sich zur Überwinterung von Eidechsen 4 Fragen: 1. wen? 2. wann? 3. wie? Und 4. wie lange? Auf diese 4 Fragen soll im in diesem Bericht eine Antwort gegeben werden.

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The longevity of several lacertid lizard species in captivity is reported. The conditions of keeping, which have been successful throughout many years, are briefly presented.

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The Columbretes archipelago consists of a group of small volcanic islets located in the western Mediterranean near the east of the Iberian Peninsula. Four of its islands are inhabited by the wall lizard Podarcis liolepis, whose populations have been considered vulnerable. The purpose of this study was to assess the level of genetic diversity across the archipelago and the possible evolutionary origin of the Columbretes lizard populations. Additionally, we investigated the evolu-tionary ecology of these populations using a DNA-based metabarcoding approach to characterise both their microbiota and trophic interactions. The genetic results reported very low genetic diversity and corroborated the conspecificity between insular populations and P. liolepis from the mainland (Peñagolosa region). The results of the metabarcoding analyses based on faecal samples were in accordance with an omnivorous ecology, suggesting that specific microbiota communities in the insular populations might be correlated with differences in host ecology and phylogeny. These results are a valuable contribution to the current understanding of the evolution of Columbretes’ lizards and provide important information for conservation management.

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Genomic divergence was studied in 10 small insular populations of the endangered Balearic Islands lizard (Podarcis lilfordi) using double digest restriction-site associated DNA sequencing. The objectives were to establish levels of divergence among populations, investigate the impact of population size on genetic variability and to evaluate the role of different environmental factors on local adaptation. Analyses of 72,846 SNPs supported a highly differentiated genetic structure, being the populations with the lowest population size (Porros, Foradada and Esclatasang islets) the most divergent, indicative of greater genetic drift. Outlier tests identified ~ 2% of loci as candidates for selection. Genomic divergence-Enviroment Association analyses were performed using redundancy analyses based on SNPs putatively under selection, detecting predation and human pressure as the environmental variables with the greatest explanatory power. Geographical distributions of populations and environmental factors appear to be fundamental drivers of divergence. These results support the combined role of genetic drift and divergent selection in shaping the genetic structure of these endemic island lizard populations.

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Genomic divergence was studied in 10 small insular populations of the endangered Balearic Islands lizard (Podarcis lilfordi) using double digest restriction‐site associated DNA sequencing. The objectives were to establish levels of divergence among populations, investigate the impact of population size on genetic variability and to evaluate the role of different environmental factors on local adaptation. Analyses of 72,846 SNPs supported a highly differentiated genetic structure, being the populations with the lowest population size (Porros, Foradada and Esclatasang islets) the most divergent, indicative of greater genetic drift. Outlier tests identified ~ 2% of loci as candidates for selection. Genomic divergence‐Enviroment Association analyses were performed using redundancy analyses based on SNPs putatively under selection, detecting predation and human pressure as the environmental variables with the greatest explanatory power. Geographical distributions of populations and environmental factors appear to be fundamental drivers of divergence. These results support the combined role of genetic drift and divergent selection in shaping the genetic structure of these endemic island lizard populations.

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A complete catalogue is provided for the type specimens of lacertid lizards in the herpetological collection of the Zoological Museum, Berlin, as of December, 1993. The collection contains a total of 514 type specimens, representing 63 taxa, of which 42 are currently regarded as valid at the specific or subspecific level. Types representing an additional four taxa appear to have been lost from the collection. The collections are especially rich in African lacertid types and in historically significant specimens collected early in the Nineteenth Century by Pallas, Eversmann, and Hemprich & Ehrenberg. Also present are the type series of many subspecies of Podarcis lilfordi and P. pityusensis described by Eisentraut.

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Here we address the validity of the assumption of the founder effect hypothesis that considerable phenotypic variation exists in the source population. Specifically, we examine variation in color pattern within the population of Podarcis lilfordi that inhabits Cabrera, the largest island occupied by this species. The population of Cabrera was the putative source for the other islets of the Cabrera archipelago. During the last glaciations, these islands were all connected by land bridges and presumably inhabited by a single population. Because the size of Cabrera exceeds that of the other islets by a factor 10 to 10.000, it seems reasonable to assume that its lizard population retains characteristics of the historical source population. We provide quantitative information on the within population variation in dorsal and ventral coloration and examine three sources of individual differences in coloration: size related shifts, sexual differences, and microgeographic variation. We also develop hypotheses about the re!ationship between the observed within population variation and the among population differences in color patterns.

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Oganismal performance abilities occupy a central position in phenotypic evolution; they are determined by suites of interacting lower-level traits (e.g., morphology and physiology) and they are a primary focus of natural selection. The mechanisms by which higher levels of organismal performance are achieved during evolution are therefore fundamentally important for understanding correlated evolution in general and coadaptation in particular. Here we address correlated evolution of morphological, physiological, and behavioral characteristics that influence interspecific variation in sprint speed in a clade of lacertid lizards. Phylogenetic analyses using independent contrasts indicate that the evolution of high maximum sprinting abilities (measured on a photocell-timed racetrack) has occurred via the evolution of (1) longer hind limbs relative to body size, and (2) a higher physiologically optimum temperature for sprinting. For ectotherms, which experience variable body temperatures while active, sprinting abilities in nature depend on both maximum capacities and relative performance levels (i.e., percent of maximum) that can be attained. With respect to temperature effects, relative performance levels are determined by the interaction between thermal physiology and thermoregulatory behavior. Among the 13 species or subspecies of lizards in the present study, differences in the optimal temperature for sprinting (body temperature at which lizards run fastest) closely matched interspecific variation in median preferred body temperature (measured in a laboratory photothermal gradient), in- dicating correlated evolution of thermal physiology and thermal preferences. variability of the preferred body tem- peratures maintained by each species is, across species, negatively correlated with the thermal-performance breadth (range of body temperatures over which lizards can run relatively fast). This pattern leads to interspecific differences in the levels of relative sprint speed that lizards are predicted to attain while active at their preferred temperatures. The highest levels of predicted relative performance are achieved by species that combine a narrow, precise distribution of preferred temperatures with the ability to sprint at near-maximum speeds over a wide range of body temperatures. The observed among-species differences in predicted relative speed were positively correlated with the interspecific variation in maximum sprinting capacities. Thus, species that attain the highest maximum speeds are (1) also able to run at near-maximum levels over a wide range of temperatures and (2) also maintain body temperatures within a narrow zone near the optimal temperature for sprinting. The observed pattern of correlated evolution therefore has involved traits at distinct levels of biological organization, that is, morphology, physiology, and behavior; and trade- offs are not evident. We hypothesize that this particular trait combination has evolved in response to coadaptational selection pressures. We also discuss our results in the context of possible evolutionary responses to global climatic change.

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In this article an introduction is given on the geological history leading to the separation of Podarcis lilfordi (GÜNTHER, 1874) and Podarcis pityusensis (BOSCÁ, 1883) as separate species, as well as a Holocene sea level rise model which combined with bathymetric data leads to an estimation of recent divergence time in populations of the Balearic lizards.

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New data on estimated divergence times of the populations of lacertid lizards in the Balearic Islands are provided in this second update of the October 2011 article: Estimating recent divergence time in populations of Podarcis lilfordi (GÜNTHER, 1874) and Podarcis pityusensis (BOSCÁ, 1883) (VAN DEN BERG 2011), which received its first update May 2012. In most cases better estimations of divergence times were available by using the NAVIONICS SonarCharts™webapp.

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In this article we make some notes on the smallest islet populations of Podarcis pityusensis (BOSCÁ, 1883) and Podarcis lilfordi (GÜNTHER, 1874), with a first description of two populations on Escull de Figueretes (Ibiza) and Carbó Petit (Menorca).

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It is reported about the rediscovery of a population of the Balearic Lizard (Podarcis lilfordi) on the Illa de Ses Mones in the harbour of Port d´Addaia. This population has been considered to have become extinct during the 1990s due to the introduction of the Italian Wall Lizard (Podarcis siculus). Descriptions of the island and the lizards are given and for the first time it is reported about the sympatric occurrence of Podarcis lilfordi and P. siculus. Because in quite a lot of publications the nearby Illot d´en Carbó has been confused with the Illa de Ses Mones the taxonomic status of the rediscovered Podarcis lilfordi population from the Illa de Ses Mones is discussed in this paper.

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We report on our observations on Podarcis lilfordi (GÜNTHER, 1874) during our 8 day trip to the natural park of s’Albufera des Grau (Spain/Menorca) and give preliminary conclusions on the status of some populations.

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We report on our observations on Podarcis lilfordi (GÜNTHER, 1874) and other Menorcan herpetofauna during our 12 day trip to Menorca (Balearics, Spain). 13 populations of Podarcis lilfordi were surveyed, 101 specimens were measured and photographed in detail, from which 84 specimens were “buccal-swabbed” for DNA samples. The subspecific status of Hemidactylus turcicus spinalis from Addaia Gran is discussed and rejected.

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More than three decades of fascination for the endemic Balearic sisterspecies Podarcis lilfordi (GÜNTHER, 1874) and Podarcis pityusensis (BOSCÁ, 1883), resulted in 30 trips (1980-2013) to the home of these lacertid lizards, in which we studied their ethology as well as their distribution and geographical differences in pattern and coloration. In comparison to prior scientific studies that led to an inflationary description of subspecies, we often found wide variations within populations and their subspecific characteristics. The question “To be distinct, or not to be distinct” is, to our opinion, not answered correctly in most cases. In order to gather data for a future revision of the present subspecific order, we started in 2011 to collect data of these lizards in a structured way, and storing this data in a free accessible database (www.pityusensis.nl). Later in 2011 we enhanced our dataset by gathering tissue samples of the lizards, using the non invasive technique of buccal swabbing, for future accompanied DNA research.

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Fifteen microsatellite loci are described for the lizard Podarcis lilfordi from the Balearic Islands. Loci were isolated from partial genomic libraries that had been enriched for AAAG and ACAG repeat sequence. All loci were highly polymorphic (six to 19 alleles) in a sample of 26 individuals from the island of Dragonera. Observed and expected heterozygosities ranged from 0.46 to 0.92 and 0.78 to 0.95, respectively. These loci will be used to study the evolutionary history of different forms, the occurrence of cross-islet introductions, and the validity of subspecific designations in this species.

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As aconsequence of the general popularity of classic Greek and Roman culture in the 19th century Germany, a renewed interest arose also for the Mediterranean fauna. Along with the Darwinian influence on evolutionary biology in the second half of the 19th century, Mediterranean lizards, particularly lacertids, became favoured study objects. The lizards served as model organisms for the earliest steps of speciation (formation of `varieties` or `races`) and shed light on adaptations to extreme, in particular insular, environments.Together with the contemporarily emerging concept of the geographical subspecies, the number of intraspecific taxa described and names erected grwe considerably. I review the relevant work of the most important zoologists from the German-speaking zone who took part in the exploration of Mediterranean amphibians and reptiles. Many of them had a much wider scope, both systematically and geographically, but nevertheless contributed significantly to Mediterranean herpetology. I lay special emphasis to the study of Balearic Islands lacertids through German-speaking authors.

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In the herpetological collection of ZFMK 528 scientific species group names are represented by type materi- al. Of these, 304 names are documented by primary type specimens (onomatophores) while for 224 further names sec- ondary type specimens (typoids) are available, ranging chronologically from 1801 to 2010. The list is a shortened pred- ecessor of a comprehensive type catalogue in progress. It lists name bearing types with their catalogue numbers includ- ing information on further type series members also in other institutions, while secondary types are listed only by pres- ence, both in ZFMK and other collections including holotype repositories. Geographic origin and currently valid names are also provided.

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We here reply to the arguments put forward by ARNOLD (2000) and LANZA & BOSCHERIN (2000) concerning the gender of the genus Podarcis. ARNOLD`S argument that a change of endings ot adjective flectible species names threatens stability is rejected by clearly following the articles of the current edition of the Code (ICZN 1999). We finally conclude that the gender of Podarcis must be masculine for the following reasons: (1) WAGLER (1830) did not determine the gender by combination with any species name nor by statement, (2) the name Podarcis is of common variable gender, (3) the Principle of First Reviser does not apply to determination of gender of names, (4) the Code clearly states that a name of common variable gender is to be treated as masculine.

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Some notes are given on keeping P. lilfordi in captivity. These animals inhabit the small islands around Mallorca and Menorca. Many subspecies have been described from different islands. Keeping these animals is rather easy, but breeding is more difficult, since less than a third of the eggs is fertilized. It`s my experience, that they lay more clutches with often more eggs than suggested in Boh me (1986). Clutches consisting of six eggs and a yearly production of up to six clutches are reported. On average 3.5 clutches consisting of 3.25 eggs are produced each year during most of their reproductive life. Incubation time ranges from 26-65 days, depending on breeding temperature. At 29°C they tend to hatch at 30-35 days, but sometimes incubation lasts for more than 40 days. Most eggs are laid in April, but some clutches are produced as early as the beginning of March or as late as the beginning of June. On average different clurches of a female are separated by 21 days. In spite of the not optimal breeding results, the amount of animals taken care of by the author is increasing yearly. All the individual animals take part in the studbook lilfordi. The founder-animals of this studbook-population are seven males and four females. Together with nine other people, including two in England, a total population of 156 animals was accounted for in 1998. It is difficult to find new studbook participants, that can adopt some offspring.

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Reptiles and amphibians from temperate zones can be kept in outdoor terrariums. Outside there is often more room for larger dwellings than inside the house. Measures have ro be taken to prevent mice, moles, cars and so on ro gain access to rhe interior. At some spot the animals have to find refuge during high temperatures and during hibernation. The author prefers glass covered terrariums, for instance glass-houses, for sunlight can create high tempera- tures even in early spring and late autumn. During rhe summer, part of the glass is removed to prevent excessive hearing. In winter a thick layer of dry lea- ves is applied when it starts freezing. Good results are obtained with Podarcis sicula, Podarcis lilfordi and Lacerta viridis in this way. On several spots the weekly highest and lowest tem- peratures are registered, for instance in a sunny spot, in the shadow and in rhe place of hibernation. Diagrams are shown representing rhe yearly varia- tion in these temperatures. Keeping animals this way gives an extra dimension to our hobby.

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Extensive studie on the natural values of Illa de l`Aire and proposals for conservation.

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Lacertid lizards frequently shed the outer layers of the epidermis of the paired male intromittent organs, the hemipenes. The hemipenial sloughs so formed are saclike and reproduce all the external features of the hemipenes in great detail. Sloughs are deposited immediately after the first defecation of the day and are produced almost every morning during the breeding season. I have observed these in 48 lacertid species, including members of the genera Acanthodactylus, Adolfus, Algyroides, Gallotia, Holaspis, Lacerta s.l., Latastia, Podarcis, Psammodromus, and Takydromus. As these forms represent all three subfamilies of the Lacertidae, the phenomenon is likely to have been present in the common ancestor of the family. It may even be a general squamate feature, as it has also been observed in the distantly related varanid Varanus acanthurus. Frequent shedding of hemipenial sloughs violates pan-epidermal synchrony, the belief that the epidermis of squamates is shed simultaneously over all parts of the body, and indicates that the hemipenial epidermis is under different hormonal control from the rest of the skin. The function of frequent shedding of the hemipenial epidermis is not known for certain, but there is a wide range of possible hypotheses. Some of these are involved in increasing the efficiency of copulation and ameliorating its costs, while others emphasise the possible signalling function of the hemipenial sloughs.

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The interspecific relationships among female size, clutch size, egg size, and hatchling size were examined for 64 European lacertids. The eggs of all species increased linearly in both linear dimensions and mass during incubation. Across species initial egg mass was positively correlated with juvenile mass, with an allometric relationship exponent of 0.87. Initial egg mass across species increased proportionally with female mass to the power of 0.57. Moreover, an increase in maternal mass was also accompanied by an increase in clutch size. The number of eggs per clutch across species scaled with female mass to the power of 0.39. Removing the effect of female mass resulted in a negative correlation between egg mass and clutch size. Species for which the average egg size was lower than expected on the basis of female mass, tended to have larger relative clutch size. The total egg mass per clutch was about one third of female mass (exponent 0.94).

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The Balearic Islands are an archipelago located in the Western Mediterranean Sea. Their isolation from the mainland allowed the establishment of different faunas on each island. In Mallorca, the Pliocene fauna was composed of the so-called Myotragus-fauna (mainly consisting of a bovid, a glirid and a soricid). In Menorca, it was constituted by the giant rabbit-fauna (mainly consisting of a giant rabbit and a tortoise), and in the Pityusics by a tortoise, a lizard and two rodents. A main faunal turnover took place during the Late Pliocene or Early Pleistocene: the Myotragus-fauna reached Menorca and replaced the giant rabbit fauna. In the Pityusics, all mammals and the tortoise became extinct before the Late Pleistocene for unknown reasons, leaving birds and the lizard as the only vertebrates of these islands. Almost all the endemic vertebrates of the Balearics became extinct probably due to the first human arrival to the islands.

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The Herpetological Collection of the Trieste Natural History Museum has almost 700 specimens of European Sauria belonging to about 33 taxa, including all the lacertids of northern Adriatic re- gions. The origin of the collection dates back to the foundation of the Museum of Trieste in 1846, but it was increased mainly between 1871 and 1939. The Herpetological Collection of the Trieste Natural History Museum has a great scientific and historical importance; it documents the varia- tion of the composition and distribution of northern Adriatic Sauria fauna during this century, in- cluding endemic varieties typical of little islands.

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1. Ecological energetics and water fluxes were compared between populations of the lacertid lizard Podarcis lilfordi from the Menorcan islets of Aire (Illa de l`Aire) and Nitge (Illa des Porros) (Balearic Islands. Spain) during a non-reproductive summer period using the doubly labelled water technique. 2. Lizards from Aire (Illa de l`Aire) were larger than those from Nitge (Illa des Porros) (9.6±0.58 g vs 5.1±0.38 g, respectively) and consequently had higher field metabolic rates (FMR) (1.739±0.151 kJ daysup-1/sup vs 1.255±0.977 kJ daysup-1/sup). 3. FMR were lower in the Aire (Illa de l`Aire) population, when the effects of the differing body masses were removed. 4. There were substantial differences in food availabilities between the two islets and this was reflected in strong dietary differences between the lizard populations. 5. Feeding constraints were potentially lower in Aire (Illa de l`Aire) owing to (a) greater arthropod availability, (b) greater abundance of edible flowers, and (c) lower lizard density. 6. We suggest that a reduction in constraints on food intake could enable more efficient foraging by Aire (Illa de l`Aire) lizards, and so explain their lower mass-independent FMR. 7. Although omnivory in Aire (Illa de l`Aire) lizards appeared to increase the amount of preformed water obtained from the food, no differences in mass-independent water flux were found, probably because drinking represented the primary source of water intake.

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Population density in the lacertid lizard Podarcis lilfordi on the Mediterranean islet of Nitge (Illa des Porros), Menorca, Balearic Islands, was found to be 12 190 ind · ha-1 (SE, ±2135), exceeding densities reported for other island or mainland lizard populations. Field metabolic rates in P. lilfordi were measured by the doubly labeled water method, allowing estimation of a population metabolizable energy demand of 13.86 MJ · ha-1 · day-1-only 9.8% of that for a theoretical mammal population of the same body mass and density. Energy demand was considerably higher than that estimated for other lizard populations, primarily due to high population density but also because of high individual daily energy expenditure (1255 KJ · day-1; body mass=5.13 g). Field metabolic rates were partitioned into maintenance and activity components by respirometry of captive animals at field body temperatures. Activity metabolism formed the main component (77.4%) of total respiratory metabolism resulting from a combination of long daily activity periods (ca. 12 h), and greatly elevated metabolism during activity (5.7 times greater than resting levels). It is hypothesized that low food availability per individual constrains the time-energy budget of this species, obligating long periods of intense foraging.

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Phylogenetic relationships and timings of major cladogenesis events are investigated in the Balearic Island lizards Podarcis lilfordi and Podarcis pityusensis using 2675 bp of mitochondrial and nuclear DNA sequences. Partitioned Bayesian and Maximum Parsimony analyses provided a well-resolved phylogeny with high node-support values. Bayesian MCMC estimation of node dates was investigated by comparing means of posterior distributions from different subsets of the sequence against the most robust analysis which used multiple partitions and allowed for rate heterogeneity among branches under a rate-drift model. Evolutionary rates were systematically underestimated and thus divergence times overestimated when sequences containing lower numbers of variable sites were used (based on ingroup node constraints). The following analyses allowed the best recovery of node times under the constant-rate (i.e., perfect clock) model: (i) all cytochrome b sequence (partitioned by codon position), (ii) cytochrome b (codon position 3 alone), (iii) NADH dehydrogenase (subunits 1 and 2; partitioned by codon position), (iv) cytochrome b and NADH dehydrogenase sequence together (six gene–codon partitions), (v) all unpartitioned sequence, (vi) a full multipartition analysis (nine partitions). Of these, only (iv) and (vi) performed well under the rate-drift model. These findings have significant implications for dating of recent divergence times in other taxa. The earliest P. lilfordi cladogenesis event (divergence of Menorcan populations), occurred before the end of the Pliocene, some 2.6 Ma. Subsequent events led to a West Mallorcan lineage (2.0 Ma ago), followed 1.2 Ma ago by divergence of populations from the southern part of the Cabrera archipelago from a widely-distributed group from north Cabrera, northern and southern Mallorcan islets. Divergence within P. pityusensis is more recent with the main Ibiza and Formentera clades sharing a common ancestor at about 1.0 Ma ago. Climatic and sea level changes are likely to have initiated cladogenesis, with lineages making secondary contact during periodic landbridge formation. This oscillating cross-archipelago pattern in which ancient divergence is followed by repeated contact resembles that seen between East-West refugia populations from mainland Europe.

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The author describes his observations on Podarcis lilfordi on Mallorca. Podarcis lilfordi gigliolii was found in great numbers on the island Dragonera, west of Mallorca. The melanistic P. l. jordansi was found in the port of Colònia de Sant Jordi in Mallorca. There it inhabits a small remaining part of the former small island ‘Frailes’, that is now connected to the main island.

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This thesis comprises part of a wider project that addresses the evolution of Mediterranean lizards of the genus Podarcis (Wagler, 1830), and is mainly focused on insular populations. This genus is widespread across the Mediterranean basin. They exhibit a great intraspecific variability in morphological traits. In particular, melanic and non-melanic populations (which are completely green or brown, and/or with intermediate coloration) are found on different islands. The causes for this variability remain unknown. The Podarcis genus contains various insular endemism such as Podarcis tiliguerta from Corsica and Sardinia islands, and P. lilfordi and P. pityusensis from the Balearic archipelago. The Mediterranean basin is considered a biodiversity hotspot due to the presence of an exceptional number of endemic species and Podarcis provides an important component of this biodiversity. It can provide information on the effects of fragmentation and/or degradation of habitat. Analyses of Podarcis also have important implications for conservation of the group itself: understanding the evolutionary framework provides a basis for future conservation actions. The present thesis is focused on the molecular study of the evolution of several Mediterranean Podarcis. It aims to build on and extend previous studies that made evolutionary inferences from just the mitochondrial DNA. This is achieved by analysing several nuclear markers (MC1R, RAG1, APOBE28, BLC9L, KIAA2018 and KIF24) in combination with mtDNA data. The main aim is to address two important evolutionary questions: i) Factors determining melanism in insular populations P. lilfordi and P. pityusensis present an important colour variation and polymorphism in the MC1R gene has been related to pigmentation in other species. Therefore, the relationship between DNA substitutions and melanism in different populations was studied. We did not detect any differences in the MC1R sequence that we analysed and so this sequence does not appear to be the basis of the colour variation in these Balearic Podarcis. Differences in gene expression were also compared between melanic and nonmelanic individuals, but no differences that were directly related to MC1R expression were detected. Nevertheless, the transcriptome profiles of melanic and non-melanic individuals from two populations of P. lilfordi did show some differences. The main differences found between the two groups were: non-melanic samples showed overexpression of stress-response genes, while melanic individuals had higher metabolic rates and an increased inflammatory response to exogenous antigens. Despite finding differences in expression, our study was unable to reveal major insights into the genetic basis of melanism in these island lizards. ii) Phylogeny and phylogeography of different endemic species. This work contributes important findings relevant to the systematics and evolution of the species P. tiliguerta endemic to Corsica and Sardina. Using Bayesian phylogenetic dating, we determined that this species originated ~11 Ma ago. Both markers (nuclear genes and mtDNA) showed a high level of intraspecific divergence, especially between Corsica and Sardinia. Ancient divergence (which was estimated at 9.5 Ma ago) and associated high levels of between-island lineage sorting in nuclear markers support the view that Corsican and Sardinian populations should be recognized as two different species. Podarcis were also studied from the Columbretes archipelago, a small island group off the coast east of Spain. Populations were previously recognized as a subspecies of P. hispanica or as P. atrata species. However, the suitability of this taxonomic designation has been made unclear by recent systematics studies of Podarcis that have led to major taxonomic changes. We used nuclear and mitochondrial genes to define their phylogenetic relationships. Columbretes populations were found to be most closely related to the new taxon P. liolepis.

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The association between polymorphism at the mc1r locus and colour variation was studied in two wall lizard species (Podarcis lilfordi and P. pityusensis) from the Balearic archipelago. Podarcis lilfordi comprises several deep mitochondrial lineages, the oldest of which originated in the Pliocene, while much shallower mitochondrial lineages are found in P. pityusensis. Here, we examined whether specific substitutions were associated with the melanic colouration found in islet populations of these species. Homologous nuclear sequences covering most of the mc1r gene were obtained from 73 individuals from melanic and non-melanic Podarcis from different populations (the entire gene was also sequenced in six selected individuals). MtDNA gene trees were also constructed and used as a framework to assess mc1r diversity. Mc1r showed greater polymorphism in P. lilfordi than in P. pityusensis. However, we observed no substitutions that were common to all melanic individuals across the two species. Only one significant association was detected in the mc1r partial sequence, but this was a synonymous A/G mutation with A alleles being more abundant in melanic populations. In addition, there were no associations between the main dominant phenotypes (green and brown, blue and yellow spots and ventral colour) and synonymous or non-synonymous substitutions in the mc1r gene. There was no statistical evidence of selection on mc1r. This study suggests no relationship between mc1r polymorphism and colour variation in Balearic Podarcis.

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Aim  The genetic structure of many plant species is heavily dependent on their pollinators and seed dispersers, and can thus be altered if either of the associated mutualistic interactions is disrupted. In this study we assess the genetic diversity and structure and infer the seed/pollen gene-flow patterns among insular populations of Daphne rodriguezii, a shrub pollinated and dispersed by animals that has lost its only disperser (the lizard Podarcis lilfordi) in most of its populations. Location  The island of Menorca and the islet of Colom (Balearic Islands, Western Mediterranean). Methods  To assess the contribution of gene flow via pollen and seeds to the genetic structure of D. rodriguezii we used amplified fragment length polymorphisms (AFLPs; seeds and pollen) and plastid DNA sequences (cpDNA; seeds). We sampled individuals from all population nuclei of the species (12–19 adults per population): one population in Colom, where the plant–lizard interaction persists, and four in Menorca, where the seed dispersal mutualism disappeared with the extinction of the lizard. Results  The highest heterozygosity values were found in Colom and in its closest population (Favàritx), whereas values were lower in the smallest Menorcan populations, which also had higher relatedness among individuals. We found distinct genetic signals between AFLP and cpDNA analyses. While AFLP markers showed low differentiation between populations, cpDNA showed a clear differentiation between them. Main conclusions  Our results point to negative impacts of the disperser loss on genetic diversity and relatedness in the smaller and more isolated populations. They also suggest an old isolation by seeds, probably occurring well before the extinction of the lizard (c. 2000 years ago). Gene flow was maintained via pollination; however, the seed disperser loss may ultimately hinder pollinator-mediated gene flow, as a result of reduced probabilities of effective pollination among increasingly distant and scarce individuals.

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West European Rock lizards, Lacerta (Iberolacerta) have small widely separated ranges in highland areas. Mitochondrial and nuclear DNA sequences corroborate the monophyly of the group and show it is not closely related to any of the other Rock lizards with which it was formerly placed in Archaeolacerta, an assemblage for which there is no evidence of clade status. L. (Iberolacerta) consists of four main units: L. (I.) horvathi of NW Croatia and neighbouring regions; the Pyrenees species, L. (I.) bonnali, L. (I.) aranica and L. (I.) aurelioi; L. (I.) cyreni of the Iberian Sistema Central, with distinctive populations in the Sierras de Béjar,Gredos and Guadarrama; and L. (I.) monticola of the Serra da Estrela of Central Portugal and NWSpain, this unit also contains L. (I.) cyreni martinezricai of La Peña de Francia, W. Spain and a distinctive population in the Montañas de Sanabria. L. (Iberolacerta) has persisted in some mountain ranges for at least 4.2±1.4Ma and may have been restricted tomountains by competition from Wall lizards (Podarcis). Its clade status shows it has lost range extensively and has produced few external branches since its initial fragmentation. In contrast, Podarcis diversified about the time L. (Iberolacerta) fragmented, producing a series of widespread lineages that have persisted until the present time. The mainly European subfamily Lacertinae, to which both L. (Iberolacerta) and Podarcis belong, diversified rapidly 13–9 Ma ago, probably largely replacing other lacertid lizards of earlier origin. As another round of replacement started at approximately 9 Ma ago with the spread of Podarcis, this may be a recurrent phenomenon in the evolution of some lizard communities.

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A parasitological survey was carried out to determine the relationships between the helminth fauna and biological traits of the hosts in three Algerian populations of Podarcis lizards belonging to two different evolutionary lineages. Size, sex, and locality of collection, as well as the infracommunities and component communities, were analyzed. Very low values of parasite infection parameters and diversity were found in all three populations. This is in accordance with the feeding habits of these lizard hosts, which only eat animal prey and no plant matter. Spauligodon saxicolae (Nematoda: Pharyngodonidae), a specialist in lizards, is reported here for the first time in Africa. This nematode was the dominant parasite species for the three populations of lizards regardless their phylogenetic lineage, size, sex, and environmental conditions.

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Una nueva especie, Spauligodon cabrerae n. sp. se describe en el intestino de Podarcis lilfordi kuligae Muller, 1927, lacertido de la isla de Cabrera (Islas Baleares). El macho se caracteriza por la presencia de cono genital con cortinilla, ausencia de espicula y papilas adanales con la base expandida. La hembra presenta espinas en la cola y los huevos son alargados y con extremos redondeados.

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This study exarnines whether rhe lit.ard kxhrcis lilfonli is a legitimate dispenier ol`the rare lüediterranean planlWithania frutescens by using the biochemical tes of rriphenyl-2H-tetraz-oliunt chloride lirr testing seed viability- This lizard eals the fiesh fiuits of the plants and defecates intact seeds which have been retained I to 3 d in their gut. Viability of seeds recoveretj fr0m tbeces was very high and comparable to lhe viability of liesh seeds. Seed dispersal by this lizard in the Balearie islands nrav tncilitate population expansiort ol`this rare plaDt in the Balearics.

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I tested predictions of the hypothesis that a longer seed passage time through the gut of the lizard Podarcis lilfordi enhances germination performance in the plant Withania frutescens. I compared germination success and germination time between seeds that were ingested by lizards and control seeds that were not. I also explored relationships between natural variation in seed passage time and germination performance. Germination success did not differ between ingested (63 %) and non-ingested seeds (56 %); there was no significant relationship between germinability and retention time. Germination time did not differ between ingested and non-ingested seeds, and was unrelated to retention time. Hence, I found no support for the hypothesis that prolonged retention times should improve germination performance. In addition, this is a pilot study stressing the importance of reptiles as seed dispersers, at least in certain habitats.

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We report reproductive characteristics (clutch frequency, clutch size, egg and hatchling sizes) of the island lizard Podarcis lilfordi, originating from Cabrera, and studied in the laboratory. Individual females produced two or three consecutive clutches, composed of 2-4 eggs with an average mass of 0.63 g. Both clutch size and average egg mass were independent of female body length, and did not differ between the first and subsequent annual clutches. Among-clutch differences in egg mass were negatively correlated with clutch size, and this trade-off is independent of female size. Larger clutches were also composed of less elongated (i.e., rounder) eggs than are smaller clutches, suggesting that limitations posed by the females` body volume, rather than by restrictions of energy availability, induce the phenotypic trade-off between egg size and numbers. Egg shape was also related to female size: larger females laid shorter but wider eggs than smaller individuals, suggesting that egg width is constrained by the width of the female`s pelvic girdle. Relative to other European lacertids with similar adult female body length, P. lilfordi produces clutches that are composed of very few, but extremely large eggs.

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We discuss three aspects of the thermal biology of lacertid lizards. First, we provide an overview of the available data on field body temperatures (Tb), the thermal sensitivity of various performance functions and selected body temperatures in different species of lacertid lizards. We also briefly summarise information on the mechanisms of thermoregulation. Second, we discuss recent developments to estimate the »precision« of thermoregulation, and the contribution of distinct behavioural mechanisms. Finally, we revise available evidence for the existence of evolutionary adjustments of thermal characteristics in lacertid lizards. Existing studies have mainly dealt with within- and among-species differences in thermoregulatory behaviour (selected temperatures) and thermal physiology of adults (optimal temperatures, heating rates). Available data provide only limited evidence for clear-cut evolutionary shifts in thermal physiology characteristics along climatic gradients.

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his study examines whether the lizard Podarcis lilfordi is a legitimate disperser of the rare Mediterranean plant Withania frutescens by using the biochemical test of triphenyl-2H-tetrazolium chloride for testing seed viability. This lizard eats the fresh fruits of the plants and defecates intact seeds which have been retained 1 to 3 d in their gut. Viability of seeds recovered from faeces was very high and comparable to the viability of fresh seeds. Seed dispersal by this lizard in the Balearic islands may facilitate population expansion of this rare plant in the Balearics.

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I examined, under laboratory conditions, the effect of the Balearic lizard Podarcis lilfordi, on germination performance of the plant Lycopersicon esculentum (Solanaceae). The time of germination was significantly reduced after ingestion by lizards, but the final percentage of germination (after 10 days) did not differ betwe- en seeds consumed by lizards (91 %) and those not ingested (98 %). The amplitude of daily temperature fluctuations to which seeds were exposed had a significant effect on germination time, but not on the final percentage of germination. Small daily temperature fluctuations (± 3,5 °C) reduced germination time compared to lar- ger ones (± 5,7 °C). Because P. lilfordi improves germination performance of L. escu- lentum, this lizard is a legitimate and efficient disperser of this plant. I also discuss how legitimate dispersers can be potential agents for the introduction of alien plants in association with human activities.

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The introduction of carnivorous mammals has led many native island species to extinction. In the Balearic Islands, the introduction of carnivorous mammals in the main islands has contributed to the extinction of the endemic lizard Podarcis lilfordi, which is an important seed disperser of many plant species. One of the introduced mammals, Martes martes (pine marten), is also known to disperse seeds and may replace the native lizard in this role in islands. However, little is known on the patterns of seed dispersal by these two different species and their possible implications for plant regeneration ability and population structure. We have compared the quality of seed deposition provided by both to the vulnerable Mediterranean shrub Cneorum tricoccon, by studying the pattern of seed distribution among sites generated by both dispersers as well as the suitability of those sites for seedling emergence and establishment. The study was carried out in two types of habitats (coastal shrublands and pine forests) and two islands (Mallorca and Dragonera). Lizards and mammals showed contrasting patterns of seed deposition and, where lizards were absent, mammals played their role as seed dispersers in pine forests but not in coastal shrublands. The lack of seed dispersal in the coastal shrubland seriously limits recruitment, by concentrating seeds under conspecifics and hindering colonisation opportunities, marking a long-term trend towards decline. The introduced predator replaces the native seed disperser in its service where it has gone extinct, although with important differences in the dispersal service provided.

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Lacertid lizards can identify and acces the quality of food, potential predators, and conspecifics using chemical cues. Lingually mediated prey chemical discrimination occurs in all species tested, with one posible exception. Omnivorous species identify both prey and plant foods using chemical cues, but carnivorous species identify only prey chemicals, suggesting that correlated evolution may have occured betwen plant diet and chemosensoryresponse to plant cues.Protein and fat elictelevated tongue-flicking and biting, whereas sugar solutions induce concentration-dependent licking. Lacertids also detect plant defensive compounds, which may enable them to avoid intoxication. At least one lacertid can also locate fruit using airborne cues. Some lacertids that detect chemical cues from snakes that eat lizards exhibit increased rates of tongue-flicking, indicating investigation, and perform several behaviours that presumably reduce the probability of being captured. These responses are innate, appearing in hatchlings not previously exposed to predators or their chemical cues, and are known only in lacertids. Pheromonal communication is known to occur in a few lacertid species. The evidence includes elevated tongue-flicking ates in cages previously occupied by conspecifics, diffrenial tongue-flick rates indicating discrimination between chemical cues from conspecific males and females, and chemical discrimination between closely related species. There is also evidence for recognition of maternal chemical cues and those from familiar sibling by one species. Differential tongue-flick rates of fecal pellets also reveal an ability to discriminate between and individual`s own pheromones and those of other individualsn of the same sex and to detect size differences among individuals.

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Lizards use chemical cues to locate and identify prey and plant food, assess the nutritional quality of food, and detect plant toxins. Among insectivorous lizards, all actively foraging species studied respond strongly to prey chemicals sampled lingually, but ambush foragers do not. Much recent research has been devoted to assessing differential responses to food and nonfood chemicals (i.e., food-chemical discrimination) by omnivorous and herbivorous species and determining whether correlated evolution has occurred between plant diet and plant-chemical discrimination. We conducted experimental studies of food-chemical discrimination by two species of teiid lizards, the omnivorous Cnemidophorus murinus and the actively foraging insectivorous Ameiva ameiva. The omnivore distinguished both prey and plant chemicals from control substances. The insectivore exhibited prey-chemical, but not plant-chemical, discrimination, as indicated by tongue-flicking and biting. A comparative analysis using concentrated-changes tests showed that correlated evolution has occurred between plant consumption and plant-chemical discrimination in a major lizard taxon, Lacertiformes. These results extend and strengthen previous findings of similar correlated evolution to a new group and add to a growing database indicating that omnivorous lizards use chemical cues to assess both prey and plant foods.

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Escape theory predicts that flight initiation distance (FID = predator-prey distance when escape begins) increases as predation risk increases. We tested effects of variation of approach speed and directness, predator persistence, concealment, and weather conditions on FID in the Balearic lizard (Podarcis lilfordi) by ourselves simulating predators. We examined effects of directness of approach on probability of fleeing and of repeated approach on entering refuge and distance fled. As predicted, FID was greater for faster approach speed, more direct approach, during second than first approaches, and when lizards were exposed than partially concealed. Other effects of directness of approach and repeated approach also were as predicted by greater assessed risk by the lizards. The proportion of individuals that fled was greater for direct than indirect approaches. The proportion of lizards that entered refuges and distance fled were greater during the second of two successive approaches. Effects of weather on FID were complex. FID was shortest in the warmest conditions with no noticeable wind, when lizards were active. Lizards were inactive and basked in the other conditions. FID was longest at 20°C without wind, and intermediate FID occurred at 18°C in windy conditions. We present hypotheses for weather effects. Tests are needed to unravel effects of temperature and wind speed. All predictions of escape theory for simple risk factors, i.e., all except than weather conditions, were confirmed. Escape theory successfully predicts FID for these risks in P. lilfordi, other lacertids, and more broadly, in ecologically and taxonomically diverse lizards.

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Escape theory predicts flight initiation distance (FID, predator-to-prey distance when escape begins) based on fixed functions relating costs and benefits of fleeing to distance between a prey and an approaching predator. Theory accurately predicts effects of costs for fixed functions and changes in functions due to changes in predator behavior approach. Less obvious is how the effect of starting distance (predator-to-prey distance when approach begins) on FID can be explained when predator behavior does not change during approach. We simulated predators to study effects of starting distance on FID in Balearic lizards (Podarcis lilfordi). Starting distance and approach speed affected FID interactively. It increased as starting distance increased during faster, but not slower, approaches. Because risk functions are considered fixed for a given approach speed, we must explain why FID varies with starting distance, why only for rapid approach, and how risk is assessed. Because prey approached slowly assess risk as small until the predator is very close, approach from greater distance has little effect on risk curves. Because continued rapid approach suggests that the predator has detected the prey and is attacking, not merely approaching, risk varies with starting distance. Theoretical difficulty in explaining the effect of starting distance on FID disappears if risk curves vary among starting distances at faster approach speeds, but each curve is fixed. This might occur if prey use a temporal rule of thumb assigning increasing risk as duration of rapid approach increases.

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Prey often exhibit reduced escape behavior on islands where predators are absent or scarce. Models of escape and refuge use predict that prey from populations having lower predation pressure have shortened flight initiation distance (FID; distance between a predator and a prey when escape begins), reduced distance fled and tendency to enter refuge, and shortened hiding time before emerging from refuge. By ourselves simulating approaching predators, we tested these predictions for two populations of the Balearic lizard, Podarcis lilfordi (Müller, 1927), on the islets of Rei (higher predation pressure) and Aire (lower) adjacent to Menorca. FID, distance fled, and hiding time were shorter and probability of entering refuge was lower on Aire than on Rei, confirming all predictions. All effect sizes were large, indicating major differences in antipredatory behavior between islets. These findings are consistent with data for other lizards on FID and limited data on distance fled and refuge entry. The effect of predation pressure on hiding time is a novel finding. Our results and those of previous studies suggest that relaxation of predation pressure leads to reduced natural selection for maintenance of antipredatory behavior at all stages of predator–prey interactions over a relatively short time span.

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Escape theory predicts that prey monitoring an approaching predator delay escape until predation risk outweighs costs of fleeing. However, if a predator is not detected until it is closer than the optimal flight initiation distance (FID = distance between predator and prey when escape begins), escape should begin immediately. Similarly, if a change in a nearby predator’s behavior indicates increased risk, the optimal FID increases, sometimes inducing immediate escape. If a predator that has been standing immobile near a prey suddenly turns toward the prey, greater risk is implied than if the predator turns away. If the immobile predator suddenly moves its foot without turning, it might be launching an attack. Therefore, we predicted that frequency of fleeing and preparation to flee are greater when a predator turns toward than away from prey and that frequency of fleeing when a predator suddenly moves decreases as distance between predator and prey increases. We verified these predictions in the Balearic lizard Podarcis lilfordi in field experiments in which an investigator simulated the predator. Lizards fled and performed alerting responses indicating readiness to flee more frequently when the predator turned toward than away from them, and fled more frequently the nearer the predator.

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Cost–benefit models predict that hiding time in refuge increases with predation risk. Studies of diverse prey confirm this prediction for various single risk factors, but much less is known regarding joint effects of variation in multiple factors. For single risk factors, we predicted that Balearic lizards (Podarcis lilfordi) hide longer after faster and more direct approaches by predators and when predators attack persistently or remain close to the refuge. We predicted that effects of approach speed on hiding time would interact with those of directness of approach and predator proximity to the refuge. We simulated attacking predators by approaching lizards ourselves. Predictions for all single risk factors were confirmed: hiding time was greater after faster and more direct approaches, second than first attacks, and when an investigator stood closer to the refuge. These findings agree with those for other prey that are ecologically and phylogenetically diverse, suggesting that optimality theory is broadly applicable to refuge use. The predictions of interaction of approach speed were confirmed for both directness of approach and predator proximity, but the interaction between approach speed and predator proximity was opposite that predicted. Knowledge of the shapes of curves relating joint risks to hiding time are needed to use optimality theory to predict joint effects of multiple risk factors, but these shapes are unknown. Comparative studies are needed to detect quantitative effects of ecological and phylogenetic differences on hiding time.

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When a predator is immobile near an immobile prey, the probability that the predator will detect and attack increases over time. The prey’s cost of moving, thereby abandoning crypsis due to immobility, therefore decreases. Cost of not moving increases over time if movement is required for prey to conduct fitness-enhancing activities. We tested a cost-benefit model that predicts effects of factors that affect predation risk and cost of not moving on a prey’s latency to flee. Acting as simulated predators, we conducted experiments on the lizards Iberolacerta cyreni and Podarcis lilfordi. All predictions for 5 risk factors and a cost of moving factor were verified. Lizards fled sooner when the predator stood closer, approached rapidly rather than slowly before stopping, approached directly rather than indirectly, and gazed at the lizard rather than away from it, and after the second of 2 successive approaches. Latency to move was shorter in the presence than absence of a mealworm, suggesting the importance of opportunity cost of immobility. The effect of standing distance has 2 components, greater rate of detection by the predator and greater risk of being captured if detected at shorter distances. Escape theory has been highly successful in predicting how close a prey allows a predator to approach before fleeing. Our model extends an economic approach to study of escape decisions in response to an immobile predator that may be an ambush forager or an active forager that has stopped moving nearby.

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Actively foraging lizards are capable of identifying prey using only chemical cues sampled by tongue-flicking, and the relatively few omnivorous and herbivorous lizards tested similarly can identify both animal and plant foods from chemical cues. Whether lizards that eat plants respond to cues specific to preferred plant types and whether there is geographic variability in responses to cues from various plants correlated with the importance of those plants in local diets is unknown. In three populations of an omnivorous lacertid, the Balearic lizard Podarcis lilfordi, we studied chemosensory sampling and feeding responses to chemical cues from plant and animal foods presented on cotton swabs. Each lizard population is endemic to one islet off the coast of Menorca, Balearic Islands, Spain. Lizards in all three populations discriminated chemical cues from plant and animal foods from control substances. Our results extend findings of prey chemical discrimination and plant chemical discrimination in omnivores, increasing confidence that correlated evolution has occurred between plant diet and chemosensory response to palatable plants. There were no consistent differences among populations in tongue-flicking and biting responses to stimuli from flowers of syntopic and allopatric plant species. The lizards may respond to cues indicative of palatability in a wide range of plant species rather than exhibiting strong responses only to locally available plant species. Nevertheless, tongue-flicking and biting frequencies varied among plant species, perhaps indicating food preferences. In addition, there were differences among populations in tongue-flick rates, latency to bite, and licking behavior. Licking was observed in only one lizard population as a response to floral chemicals from only one of the plants species tested, raising the possibility of a population-specific linkage between identification of a particular plant species and performance of an appropriate feeding response.

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Although squamate reptiles are known to locate conspecifics by scent-trailing and to locate and identify prey by tongue-flicking substrates, an ability to locate food using only airborne cues has previously only been suspected based on observations that dead animals can be used as bait for Komodo dragons and that some nocturnal geckos aggregate on flowers. We conducted a simple field test of the ability of the omnivorous lizard Podarcis lilfordi from Aire islet (Illa de l`Aire) to find fruit hidden under opaque cups. When a board having two identical cups spaced 1 m apart, one empty and the other hiding a freshly cut piece of apricot, was placed in the habitat, lizards first contacted the cup hiding fruit at well above chance frequency. Upon contact with a cup, lizards were significantly more likely to stay next to the cup, tongue-flick at high rates, climb the cup, and attempt to bite the cup if it hid a piece of apricot. The ability to follow a concentration gradient of airborne volatile chemicals to its source is very likely mediated by olfaction, but participation by or primacy of vomerolfaction cannot be excluded.

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Specialist predators may respond strongly to sensory cues from preferred prey, but responses by generalist predators, although predicted to be less specific, are poorly known. Among squamate reptiles, diet and strength of response to chemical prey cues covary geographically in snakes that are specialist predators. There have been no previous studies of correspondence between diet and chemosensory response in lizards that are prey generalists. Actively foraging lizards discriminate between prey chemicals and control substances. It has been speculated that differential responses among prey species are unlikely in typical species that are dietary generalists. We examined this relationship in Podarcis lilfordi, an omnivorous lacertid that consumes a wide variety of animal prey. In experiments in which chemical stimuli were presented on cotton swabs, lizards responded more strongly to chemicals from a broad spectrum of prey types than to deionized water, an odorless control. These findings plus previous data showing that P. lilfordi is capable of prey chemical discrimination suggest that P. lilfordi can identify a wide range of potential prey using chemical cues. However, there was no evidence of differential response to stimuli among prey species, even in comparisons of prey included in the natural diet and potential prey not in the diet. The results, although limited to a single species, are consistent with the hypothesis that lizard species that are prey generalists do not exhibit the differential response strengths to chemical prey cues observed in snakes that have more specialized diets.

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Here we report the findings of field experiments on kleptoparasitism in the Balearic lizard, Podarcis lilfordi, from Aire, an islet offshore from Menorca.

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Optimal escape theory predicts that prey permit closer approach by predators when fleeing is more costly, but does not predict other aspects of escape such as distance fled or the likelihood of returning to the initial site in the presence or absence of a resource such as food. Because a lizard preparing to feed may lose the feeding opportunity, optimal escape theory predicts that the lizard should allow a predator to approach closer before fleeing when a stationary food source is present than in its absence. In addition, we predicted that when a predator was nearby, lizards would flee a shorter distance and return more often when food was present than absent. We presented adult males of the omnivorous Balearic lizard, Podarcis lilfordi, with a tethered piece of pear or a pebble of similar size and shape. One of us approached a lizard in a standardized manner, stopping and remaining still when the lizard fled. The other investigator recorded escape and return behaviors. Lizards in the presence of food permitted closer approach before fleeing, fled a substantially shorter distance, and were far more likely to return to the site of stimulus presentation than when a pebble was presented. These findings suggest that prey may alter several aspects of escape behavior to reduce costs due to lost opportunities, and present a likelihood that interspecific variation exists in the combination of aspects of antipredatory behavior that are modified.

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Many predation risk factors to affect escape behavior by lizards, but effects of some potential risk factors are unknown or are variable among species. We studied effects of several risk factors on escape responses by the Balearic lizard (Podarcis lilfordi, Lacertidae) on escape responses. Escape was elicited by an approaching experimenter who recorded flight initiation distance (predator-prey distance when escape begins) and distance fled. When an experimenter approached from above (upslope), flight initiation distance and distance fled were longer than when the experimenter approached from below. This novel effect suggests that lizards exposed to aerial predation might have been naturally selected to respond rapidly to predators approaching from above or that effects of path inclination of escape ability may differ between predators and prey in a manner requiring a larger margin of safety during approaches from above than below. Although sex differences in aspects of escape occur in some lizards, including lacertids, no sex difference was observed in P. lilfordi. Because vigilance and some other aspects of antipredatory behavior exhibit cortical lateralization, we tested effects of approach from the left and right sides of lizards. As predicted by optimal escape theory, side of approach did not affect flight initiation distance. Because many lizards have color vision and respond to pigmentation of conspecifics in social settings, researchers have often worn only drably colored clothing when simulating predators. This precaution may be unnecessary because flight initiation distance did not differ among investigator shirt colors (red, orange, olive).

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Island tameness (reduced escape behaviour on islands where prey have experienced prolonged relaxation of predation pressure) is known in several taxa, although the relationships between recent predation pressure and escape on islands are poorly known. We investigated escape by numerous populations exposed to differing predation pressure of two sister species of Podarcis lizards in the Balearic Islands. Our main findings are that flight initiation distance was greater in Podarcis pityusensis than Podarcis lilfordi and increased as predation pressure increased in P. pityusensis. Island tameness led to extinction of P. lilfordi on Menorca and Mallorca following anthropogenic introduction of predators; this species is extant only on nearby islets. The lack of relationship between recent predation pressure and flight initiation distance in P. lilfordi indicates that the historically acquired deficit in the ability to adjust escape behaviour to predation pressure still exists. Podarcis pityusensis, which was exposed to greater natural predation pressure before human introduction of predators, survives on Ibiza and Formentera, as well as on islets. Retention of the ability to respond to predation pressure is consistent with our finding that flight initiation distance increases as predation pressure increases among current populations.

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During encounters with predators, prey must balance the degree of risk against the loss of fitness-enhancing benefits such as feeding and social activities. Most studies of tradeoffs between risk and cost of escaping have measured flight initiation distance and time to emerge from refuge, for which theory provides robustly supported predictions. Tradeoffs involving other aspects of encounters, including distance fled and time between escape and return to a food source, have received little theoretical or empirical attention. By adapting models of flight initiation distance and time between entry into refuge and emergence, we predict effects of predation risk and cost on distance fled and time to return to a source of benefit after fleeing. Acting as simulated predators that approached at a fixed speed, we conducted an experimental field study to test the hypotheses that flight initiation distance, distance fled, and time to return to food by Balearic lizards (Podarcis lilfordi) decrease with the presence and amount of insect food. Predictions of the models were strongly supported, including those for distance fled and return time, but predictions for other cost factors and predation risk factors remain to be tested. The study site was conducted on Aire (Illa de l`Aire), an islet off the coast of Menorca, Balearic Islands, Spain in early May 2005 on sunny days between 8:45 AM and 3:50 PM when lizards were active and foraging. Aire is an ideal site for studies of tradeoffs between antipredatory behavior and foraging because the exceedingly high population density of the Aire population facilitates data collection.

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The number of simultaneously attacking simulated predators and their approach speeds and angles affected escape trajectories and flight initiation distance in Balearic Lizards (Podarcis lilfordi). Our findings confirmed predictions prey flee in directions maximizing distance from predator(s). During slow approaches, escape angle was 45° when approached by two predators at right angles and 90° when approached from opposite directions. Escape at close to 45° by lizards approached at slower speed by a single predator supports the hypothesis that prey use escape trajectories allowing them to visually monitor predators. Flight angles were closer to being straight away from a predator during faster approaches, suggesting that distance maximization may be more important than monitoring predator position when risk is great. When predators approached from opposite directions, flight angle shifted away from the faster predator, suggesting that lizards may have equalized risk from both predators based on positions and speeds. Flight initiation distance was greater for approach by predators side by side than by one only during faster approaches, suggesting that risk is a joint function of predator number and speed. Flight initiation distance was greater when predators approached at right angles than side by side, perhaps because of difficulty of monitoring multiple predators in different locations. Distance fled did not differ among treatments and may have been affected by distance to refuge. Thus, Balearic Lizards adjusted flight initiation distance and escape trajectories in ways that enhanced their abilities to avoid predation during simultaneous approaches by two predators.

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Foraging modes were described originally for insectivorous lizards, but many species are omnivorous or herbivorous. Because seeking and consuming plants might alter foraging, we studied foraging by the omnivorous Podarcis lilfordi at two sites: one where lizards licked nectar from flowers of Euphorbia paralias and the other where they sought insects. Movements per minute (MPM) did not differ among groups. Proportion of time spent moving (PTM) was similar in lizards that licked flowers and those that did not. Average speed (AS) was slower, and speed while moving (MS) was faster when foraging for nectar than for insects. Lizards foraging for nectar did not eat insects; those foraging for insects frequently ate them. For lizards foraging for prey, MPM increased as PTM, AS, and capture attempts increased and as PTM decreased. PTM increased as AS and capture attempts increased and decreased as MS increased. AS increased as MS increased. For lizards that licked, proportion of time licking (PTL) was unrelated to MPM, PTM, or AS but increased marginally as MS increased. Lizards foraging for nectar retained the PTM of lizards foraging for prey, but added a large PTL. The ancestral active foraging mode has been retained for hunting insects but modified to search for and lick nectar. While foraging for nectar, lizards greatly reduce attacks on insects, suggesting that, at a given time, an individual forages exclusively for nectar or prey. Reduced predation pressure on islands may have freed lizards to expand the diet by reducing risk during intervals exposed to view while climbing plants and licking nectar.

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Many lizards can identify food using chemical cues, but very little is known about the chemical constituents used for this purpose. We experimentally investigated responses to several lipid stimuli by the omnivorous lacertid lizard Podarcis lilfordi, which had been shown previously to be capable of identifying prey using only chemical cues and to respond to pork fat by tongue-flicking and biting. In 60-s trials in which stimuli were presented on cotton swabs, the lizards responded very strongly to pure pork fat and to oleic acid, but not to cholesterol or glycerol. Latency to bite swabs, the number of individuals that bit swabs, and the tongue-flick attack score, TFAS(R), which combines effects of tongue-flicks and bites, showed stronger responses to fat than to cholesterol, glycerol, and distilled water but did not differ significantly from responses to oleic acid. Several lines of evidence show that oleic acid elicited strong chemosensory and feeding responses. For individuals that did not bite, the number of tongue-flicks was significantly greater for oleic acid than for distilled water or glycerol, and nearly so for cholesterol. Latency to bite was significantly shorter for oleic acid than for distilled water, and TFAS(R) was significantly greater for oleic acid than for distilled water and glycerol. In combination with pilot data indicating no strong response to the waxy, saturated palmitic acid, these findings suggest that oleic acid in particular and probably other unsaturated fatty acids found in animal fat contribute strongly to the food-related responses to lipids.

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Many lizards are capable of identifying food using only chemical cues from food surfaces, but almost nothing is known about the types of compounds that are effective stimuli. We experimentally studied lingual and biting responses by a lacertid lizard, Podarcis lilfordi, to single representatives of three major categories of food chemicals, sucrose as a carbohydrate, pure pork fat as a mixture of lipids, and bovine gamma globulin as a protein. In 60-sec trials in which stimuli were presented on cotton swabs, the lizards detected all three stimuli, exhibiting more tongue-flicks, licks, or bites, or a greater tongue-flick attack score (TFAS; overall measure of response strength to prey stimuli) than to deionized water. The initial response to all stimuli was tongue-flicking, but the lizards discriminated among the types of chemical stimuli. After preliminary tongue-flicks, the lizards responded to sucrose solutions by licking at high rates, to pure pork fat by biting, and to protein by a combination of additional tongue-flicks and biting. Biting is a feeding response to prey or solid plant material. Licking is a feeding response to sugars in nectar or ripe fruit. Its frequency increased with sucrose concentration. Our data suggest that lizards can identify several types of chemicals associated with food and direct feeding attempts to sources of such chemicals in the absence of visual cues.

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Costly anti-predatory defences are used in ecological time and maintained in evolutionary time by natural selection favouring individuals that survive through their use. Autotomy of expendable body parts is a striking example of a defence having multiple substantial costs, including loss of ability to use the same defence, loss of energy, and decreased growth, reproductive success and survival following autotomy, plus the energetic cost of replacing the lost body part in species capable of regenerating them. Our study shows that autotomy in the lacertid lizard Podarcis lilfordi reduces sprint speed, indicating decreased capacity to escape as well as the loss of energy. Autotomy carries substantial cost, and thus should be avoided except as a last resort. Ease of autotomy and post-autotomic movements were studied in three populations of lacertid lizards. Two were islet populations of Podarcis lilfordi from Aire (Illa de l`Aire) (lowest predation pressure) and Colom (Illa d`en Colom) (intermediate predation pressure) off Minorca. The third was a mainland population of Podarcis hispanica, a closely related species from the mainland of the Iberian Peninsula where predation pressure is higher than on the islets. As predicted, a suite of autotomic traits increases the effectiveness of autotomy as a defence as predation pressure increases. With increasing predation pressure, the frequency of voluntary autotomy increases, latency to autotomy decreases, pressure on the tail needed to induce autotomy decreases, vigour of post-autotomic tail movements increases, and distance moved by the shed tail increases. Additional changes that might be related to predation pressure, but could have other causes, are the presence of tail coloration contrasting with body coloration except under the lowest predation pressure (Aire) and longer tails in the mainland species P. hispanica. Correspondence between predation pressure and the suite of autotomic traits suggests that autotomy is an important defence that responds to natural selection. Comparative data are needed to establish the generality of relationships suggested in our study of only three populations.

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An ability to detect plant toxins and thereby avoid eating chemically defended plants would be very beneficial for omnivorous and herbivorous lizards. We studied the ability of the omnivorous Podarcis lilfordi to detect compounds belonging to three classes of common plant toxins, as well as responses indicating aversion. Solutions of the alkaloid quinine, saponin, and the phenolic coumarin, as well as distilled water (odorless control), were presented to lizards on cotton swabs. The lizards detected all three toxins as indicated by significantly decreased tongue-flick rates and tongue-flick attack scores in comparison with distilled water. Several other variables revealed aversion to saponin, including a low number of individuals that bit swabs, avoidance of swabs after tongue-flicking, performance after tongue-flicking the swab of repeated short-excursion tongue-flicks that were directed away from the swab and did not contact any substrate, failure to respond at all in the next trial, and wiping the snout on the floor of the terrarium. Reasons for apparent differences in tongue-flicking behavior between P. lilfordi and two other omnivorous lizard species are discussed. We also showed experimentally that saponin depresses the tongueflick rate in the omnivorous Bonaire whiptail lizard, Cnemidophorus murinus. Tongue-flicking enables at least one lizard species to detect specific chemicals representing three major classes of plant toxins. It is hypothesized that this ability is a widespread adaptation to reduce ingestion of plant toxins.

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One of Darwin`s most widely known conjectures is that prey are tame on remote islands, where mammalian predators are absent. Many species appear to permit close approach on such islands, but no comparative studies have demonstrated reduced wariness quantified as flight initiation distance (FID; i.e. predator–prey distance when the prey begins to flee) in comparison with mainland relatives. We used the phylogenetic comparative method to assess influence of distance from the mainland and island area on FID of 66 lizard species. Because body size and predator approach speed affect predation risk, we included these as independent variables. Multiple regression showed that FID decreases as distance from mainland increases and is shorter in island than mainland populations. Although FID increased as area increased in some models, collinearity made it difficult to separate effects of area from distance and island occupancy. FID increases as SVL increases and approach speed increases; these effects are statistically independent of effects of distance to mainland and island occupancy. Ordinary least-squares models fit the data better than phylogenetic regressions, indicating little or no phylogenetic signal in residual FID after accounting for the independent variables. Our results demonstrate that island tameness is a real phenomenon in lizards.

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Animal diets crucially affect fitness, yet many aspects of their ultimate determinants are unknown. The distribution and extent of herbivory in lizards, its evolutionary history, and ecological factors that may favour it are discussed. Most lizards are exclusively or primarily carnivorous, yet many species eat some plants and a few are almost exclusively herbivorous. Based on a literature survey of diets of over 450 lizard species, the distribution and degree of omnivory and herbivory are described. Some plants occur in the diets of slightly over half of lizard species, and plants formed 10% or more of the dietary volume of 12.1% of species, and 90% or more of the diet of 0.8% of species. The greatest percentage of omnivorous species (> 10% plant diet), over 30% in each, and highest mean percentage plant matter in the diet are in Iguanidae, Corytophanidae, Gerrhosauridae, Agamidae, Xantusiidae, and Tropiduridae. Numerous other omnivores occur in Lacertidae and Scincidae and fewer in several additional families. Herbivorous lizards (> 90% plant volume) tend to be folivorous and to possess adaptations for processing leaves, including specialized dentition for cutting or reducing leaves, elongated intestines, colic valves that slow passage of food, and intestinal flora that digest cellulose. Omnivorous lizards lacking such specializations may eat some leaves, but consume much more fruit, flowers, and seeds, plant parts that are easy to digest, likely to be very abundant seasonally, and may be highly nutritious. Some lizards eat nectar and pollen; even sap is eaten by at least one gecko. Ontogenetic increase in plant consumption and decrease in prey consumption is known, but its generality has been controversial. Such ontogeny has been demonstrated in three iguanid species, a skink, a lacertid, two tropidurids, a phrynosomatid, and two corytophanids, but it does not occur in some other species. Thus, the presences of ontogenetic variation must be evaluated for each species. The importance of specific foods may also vary with age. Omnivory and/or herbivory have originated in many lizard families, with at least nine origins in Iguania and 23 in Scleroglossa. Origins have been rare in Gekkonoidea and Anguimorpha and common in Scincomorpha, especially in Lacertidae and Scincidae. Losses of omnivory have been much less frequent than gains. Only a few origins can account for all the herbivory in lizards. Concentrated changes tests show that there is a significant association in Lacertidae, Lacertiformes, Lacertoidea, Scincidae, and Scleroglossa between insularity and omnivory. Insular lizards may broaden their diets to compensate for limited availability of prey. Addition of other factors that reduce availability of prey, i.e. extreme aridity and cave-dwelling, to insularity, strengthened the relationship to omnivory in Lacertidae and Lacertoidea. We were unable to demonstrate a role of aridity independent of insularity, but present anecdotal evidence suggests that it may promote evolution of plant consumption. Large body size in lizards has long been associated with herbivory, and more recently, with omnivory in lacertid lizards. Using a conventional regression approach in which each species is considered to supply an independent data point, this relationship was confirmed for all lizards. Although larger species have diets with more plants, plant consumption accounts for only 9% of the variation in body length, which is not surprising given that other factors such as predation, competition, and sexual selection affect body size. The frequency of transitions body size associated with transitions to ominivory or carnivory was also examined. In Iguania, Scleroglossa, and all lizards, transitions supporting the hypothesis that omnivory favours increase in body size were significantly more frequent than nonsupporting transitions. This suggests that substantial plant consumption favours evolution of larger size, probably because of the energetic considerations first presented by Pough (1973). Because actively foraging lizards move widely through the habitat to locate prey and tongue-flick to locate prey by chemical cues, we hypothesized that they may be more likely to evolve omnivory than ambush foragers, which wait motionless for prey and do not tongue-flick to locate or identify prey. The basis of this prediction is that the wider searching of active foragers predisposes them to contact with a greater variety and quantity of plants and that chemosensory tongue-flicking used by omnivores to identify plant food might be easier to evolve in active foragers that already use pre-chemical discrimination. The prediction is supported by a significantly greater per species frequency of origins of omnivory by active foragers than by ambushers. A scenario for the progressive evolution of omnivory and herbivory from ancestrally carnivorous lizards is discussed.

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We report here a case of spontaneous limb regeneration in a wild Podarcis lilfordi lizard from the Balearic Islands. The animal had lost a hind limb, which regenerated posteriorly into a tail-like appendage. Despite not representing a functional regeneration, the growth of this structure after limb amputation suggests that survival of the individual may have been favored by the less restrictive conditions prevailing in insular environments. Nevertheless, such cases are extremely rare in lizards, with no reported cases over the last 60 years.

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The Mediterranean Sea, in particular along its northern coasts contains may archipelagos, islands, islets and rocks. Also along Spain and the north African and Levant coasts some islands are present. Most of these islands are inhabited by lacertid lizards, 39 species are known at present. Many of the species living on islands are also distributed on the mainland, while others are endemic (Algyroides fitzingeri, Lacerta bedriagae, Podarcis artratus, Podarcis filfolensis, Podarcis gaigae, Podarcis lilfordi, Podarcis milensis, Podarcis pityusensis, Podarcis raffonei, Podarcis tiliguerta, Podarcis waglerianus). There are also species introduced by man like Teira perspicillata onto Menorca. Insular populations are often restricted and due to their isolation status constantly under drought conditions. In the present paper some factors that could affect island populations are discussed. As lizards are good models to study insular ecosystems they deserve particular attention.

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The aim of the present study is to synthesise the available data on the occurrence of lacertid lizards on Mediterranean islands better to understand how far human influence is involved in the present distributional patterns of insular lacertid lizard fauna. At present, the Mediterranean islands are inhabited by several lacertid genera, including endemic species of the genera Algyroides (viz. fitzingeri), Lacerta [Archaeolacerta] (viz. bedriagae) and Podarcis (atratus, filfolensis, gaigae, lilfordi, milensis, pityusensis, raffonei, tiliguerta, waglerianus). Recently reported data shed new light on the relationships between these endemics and some continental species that have recently colonised the islands. The arrival of the latter might be directly related to the progressive human colonisation of these islands. The arising conservation problems are also considered.

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This work deals with a synthesis of data on the late Quaternary occurrence of endemic herpetofauna reported, shed new light on the permanence and extinction of autochthonous species and the arrival of continental ones. Their arrival might be directly related to the progressive advent of human colonisation of the islands, Hence, the question is how is the present insular herpetofauna connected to human intervention? In this review we show the close connection between human occupation of Mediterranean islands and present-day herpetofauna.

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Studies of the effects on insularity on the design of animal signals are scarce, particularly in lizards. Here we use Lilford’s wall lizard from Dragonera (Podarcis lilfordi gigliolii) to ask how insularity has affected its repertoire of social signals relative to mainland Podarcis. We focused on two visual signals shared by many Podarcis: UVblue patches (UBP) and visual displays. The latter include foot shakes and the raised body displays used to expose the UBP. We examined if the number or spectral characteristics of the UBP are associated with morphological traits related to individual quality. We also used visual models to measure sexual dichromatism in the UBP. We did not observe foot shakes or any other visual displays. The UBP did not covary with body condition or fighting ability in males, suggesting that this coloration does not signal individual quality. We also found very little sexual dichromatism, females having malelike UBP. We hypothesize that this pattern of reduced social signaling is due to the high population density of P. lilfordi gigliolii, which discourages territorial behavior and promotes extreme social tolerance, making most social signals unnecessary.

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Studies of the effects of insularity on animal signals are scarce, particularly in lizards. Here, we use Lilford’s wall lizard from Dragonera (Podarcis lilfordi gigliolii) to ask how island conditions have affected its repertoire of social signals, focusing on two visual signals shared by many Podarcis species: ultraviolet (UV)–blue-reflecting ventrolateral colour patches and visual displays. We examined whether the number or spectral characteristics of the UV–blue patches are associated with traits related to individual quality. We also used visual models to assess visual conspicuousness and to measure sexual dichromatism. We did not observe foot shakes or any other visual displays usually found in continental Podarcis. We found that none of the UV–blue patch variables covaried with morphometric variables indicative of fighting ability or body condition in males, suggesting that this coloration does not signal individual quality. We also found very little sexual dichromatism. In particular, the UV–blue patches of females seem over-expressed and more similar to those of males than those of continental Podarcis. Ancestral state reconstruction reveals that the lack of sexual dimorphism in the UV–blue patches is a derived condition for P. lilfordi gigliolii and other Podarcis living on small islands. Our results thus show a pattern of reduced social signalling in P. lilfordi gigliolii relative to mainland Podarcis, with some signals being lost or under-expressed (visual displays) and others losing their signalling function (UV–blue patches). We hypothesize that these changes are attributable to the high population density of P. lilfordi gigliolii, which discourages territorial behaviour and promotes extreme social tolerance, making most social signals unnecessary. More work will be needed to determine whether this is a common pattern in lizards inhabiting small and densely populated islands.

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Lizards and Eleonora’s falcon occur on many Mediterranean islets. Data given in literature and new observations concerning their asymmetrical interactions, which have been reviewed and illustrated, allow to regard those as a commensal relationship typical on these micro-insular ecosystems. Some considerations on the ecological, ecomorphological and phenological traits involved on this commensalism are also briefly discussed.

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Comparative analyses were carried out about the variability of the pileal shields of different species belonging to the family Lacertidae. The results of the comparisons have been evaluated in respect to the phylogenetical relationships existing between the different genera and species of the family.

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Several species of vertebrates exhibit spontaneous longitudinal body axis alignment relative to the Earth’s magnetic field (i.e., magnetic alignment) while they are performing different behavioural tasks. Since magnetoreception is still not fully understood, studying magnetic alignment provides evidence for magnetoreception and broadens current knowledge of magnetic sense in animals. Furthermore, magnetic alignment widens the roles of magnetic sensitivity in animals and may contribute to shed new light on magnetoreception. In this context, spontaneous alignment in two species of lacertid lizards (Podarcis muralis and Podarcis lilfordi) during basking periods was monitored. Alignments in 255 P. muralis and 456 P. lilfordi were measured over a 5-year period. The possible influence of the sun’s position (i.e., altitude and azimuth) and geomagnetic field values corresponding to the moment in which a particular lizard was observed on lizards’ body axis orientation was evaluated. Both species exhibited a highly significant bimodal orientation along the north-northeast and south-southwest magnetic axis. The evidence from this study suggests that free-living lacertid lizards exhibit magnetic alignment behaviour, since their body alignments cannot be explained by an effect of the sun’s position. On the contrary, lizard orientations were significantly correlated with geomagnetic.

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Ecological network analysis can be used to study several ecological aspects such as food web structure, mutualistic plant-pollinator interaction and the transmission of infectious diseases. However, many networks are species based, which means that individuals in the network are considered to be identical. Several studies have shown that this might be wrong. Large individual variation in a population has been observed for many species and may be due to differences between each individual in sex, age, behavior, and size. This individual variation may affect the dynamic of a population both ecologically and evolutionarily and therefore downscaling from species level to individual level may be important when studying ecological aspects for an ecological community. In this study, the diet of the endemic lizard of the Balearic Islands, Podarlis lilfordi, was examined in an individual-based network analysis. This was carried out on two islets, Na Moltona and Na Guardis, south of Mallorca, for two years (two spring seasons, one summer season and two autumn seasons). The population’s niche was expected to be determined by one of two mechanisms: that individuals would be as generalized as the population or that individuals would be more specialized than the population. Networks were made for all seasons, male individuals, female individuals, and juvenile individuals on both islets. The results showed that individuals on both islets were more specialized than their population. The all season network on Na Moltona was both nested and showed modularity. Individual body size varied much and may have been the driver of the nested pattern seen in the network. The all–season network on Na Guardis was non-nested, but showed modularity. The individual body size did not vary that much on this islet, with may be explained by the non-nested pattern of the network, due to the different monopolizing of food resources and then reduced intraspecific competition. The modularity seen on both islets emphasize the individual niche specialization, but the different modules could not be explained by grouping of individuals at same sex, age or size. Instead, the grouping seemed to be made up by a few males, some females and some juveniles, maybe genetically close related individuals, i.e. family groups restricted in space. In conclusion, the downscaling from species level to individual level when analyzing ecological aspects such as population niche width has been shown to be important. Individuals in a population differ and this individual specialization can have strong effects on the dynamics in their interacting networks.

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Background. The western Mediterranean archipelagos have a rich endemic fauna, which includes five species of reptiles. Most of these archipelagos were colonized since early historic times by anthropochoric fauna, such as ship rats (Rattus rattus). Here, I evaluated the influence of ship rats on the occurrence of island reptiles, including non-endemic species. Methodology. I analysed a presence-absence database encompassing 159 islands (Balearic Islands, Provence Islands, Corso-Sardinian Islands, Tuscan Archipelago, and Galite) using Bayesian-regularized logistic regression. Results. The analysis indicated that ship rats do not influence the occurrence of endemic island reptiles, even on small islands. Moreover, Rattus rattus co-occurred positively with two species of non-endemic reptiles, including a nocturnal gecko, a guild considered particularly vulnerable to predation by rats. Overall, the analyses showed a very different pattern than that documented in other regions of the globe, possibly attributable to a long history of coexistence.

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Mediterranean islands have complex reptile assemblages, but little is known about the factors that determine their organization. In this study, the structure of as-semblages of Squamata was evaluated based on their species richness and two measures of phylogenetic diversity (variability and clustering). I evaluated the com-position of the assemblages comparing distinct biogeographic subregions within the Mediterranean: Adriatic, Aegean, Balearic, Corsica–Sardinia, Crete, Gulf of Gabés, Ionian Sea, Ligurian Sea, Malta, Sicily, and Tyrrhenian Sea. The effect of island en-vironments and geographical isolation on the diversity metrics was assessed using generalized linear models. The analyses indicated that species richness was mostly influenced by island area and geographical isolation. Assemblages on smaller islands were poorer in species and phylogenetically dispersed, possibly as an effect of inter-specific competition. The species composition of the assemblages was determined by similar environmental drivers within the biogeographic subregions, including is-land area, island elevation, geographical isolation, and aridity. In several subregions, significant patterns of phylogenetic attraction were found in species co-occurrences, caused by the limits imposed by the island size on large predatory species

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Background Lizards of the genus Podarcis are widespread in the Mediterranean region, including islands and island archipelagos. These small-bodied lizards have a predominantly protective green-brown colouration. However, some populations display unusual patterns, in which the colouration is predominantly blue or uniformly black. This study explores the factors that influence this chromatic variation, whether environmental (climate and island conditions) or evolutionary (phylogenetic trait conservatism). The colouration of 1400 individuals (27 species) was analysed in the CIELAB colour space. Results Pagel’s λ indicated that colouration is weakly conserved within phylogenetic lineages. Although the island surface plays a key role in the chromatic variability of these lacertids, geographic isolation and climate hold less influence. The colouration of some small island populations tends to be uniform and dark, possibly due to intense intraspecific competition and lower predatory pressure. Conclusions This study highlights the importance of island populations in understanding the processes that favour the emergence of extreme phenotypes in small ectothermic vertebrates.

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En las últimas décadas se han introducido tres especies de serpientes en las Islas Baleares a través del comercio de viveros desde la Península Ibérica, su área de distribución nativa. La culebra de escalera Zamenis scalaris fue citada por primera vez en 2006 en Formentera, la culebra de herradura Hemorrhois hippocrepis en 2003 en Ibiza y la culebra bastarda Malpolon monspessulanus en 2006 en Mallorca. Actualmente, cualquier especie de la familia Colubridae que habita en Ibiza y Formentera es considerada legalmente invasora. Desde 2016, en estas dos islas se llevan a cabo campañas de control y erradicación mediante trampas cebadas con ratones vivos. Por el contrario, las especies de serpientes exóticas que habitan en Mallorca no son consideradas legalmente invasoras. En este caso, campañas de control y erradicación a pequeña escala se iniciaron en Mallorca en 2017. En el presente trabajo se resumen los estudios realizados en relación con la monitorización e impacto de estas especies en las islas de Ibiza, Formentera y Mallorca. Los resultados sugieren que el proceso de invasión se ha completado con éxito para H. hippocrepis y Z. scalaris, ya que ambas especies están bien establecidas en Ibiza y Formentera, respectivamente. La combinación de introducciones múltiples, un potencial reproductivo elevado, la gran plasticidad trófica y su adaptación climática habrían contribuido al proceso de invasión. En cuanto a M. monspessulanus, aún no se ha descrito su completa expansión en Mallorca aunque se ha comprobado su naturalización. Sin embargo, rasgos como la eurifagia y la capacidad adaptación a ecosistemas alterados, sugieren una muy probable expansión por toda la isla en el futuro. Entre los impactos se han detectado respuestas antidepredatorias comportamentales y fisiológicas de la salamanquesa común Tarentola mauritanica expuesta al olor de H. hippocrepis, hecho que evidenció que reconoce las señales químicas de la culebra de herradura. La legislación actual se ha mostrado ineficaz en cuanto a la prevención y la aplicación de protocolos de rápida actuación contra estas especies. Sin embargo, se cree que la fuerte presión de captura desde 2016 ha provocado una disminución de las densidades de población, especialmente de Z. scalaris en Formentera. El presente trabajo sugiere propuestas adicionales para gestionar las poblaciones de serpientes establecidas en las Islas Baleares y también para prevenir futuras introducciones tanto de éstas como de otras especies.

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The Balearic lizard (Podarcis lilfordi) is a native species of the Gymnesics islands, it has been cataloged as endangered by the IUCN. Because of its small population size and almost extinct in the major islands of Mallorca and Menorca. The aim of this work is to analyze the population variability, the phylogenetic relationships and the genetic structure of Podarcis lilfordi to the Cabrera Archipelago, through the use of molecular markers such as the mitochondrial DNA control region. The results reveal the presence of three clades within the archipelago, a relationship between the intrapopulation genetic variability and the surface of the islands and also it is shared haplotypes of Cabrera Gran, which suggesting that the island acted as a genetic reservoir.

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We provide a fi rst complete list of the present and lost reptile type material of the Zoologische Staatssammlung München (ZSM) and discuss various problems involved. The collection currently houses primary types of 184 taxa (128 holotypes, 44 lectotypes, and 12 taxa based on syntype series), 112 of them currently considered valid. Furthermore, 63 taxa are exclusively represented by secondary types (paratypes, paralectotypes). The ZSM collection strongly suffered from losses during World War II. Approximately 90 primary reptile type specimens or primary type series are considered to be destroyed during that time. The historical focus of the collection is the South American region. This is primarily based on material collected by Spix and Martius during their expedition to Brazil from 1817 to 1820. Primary types of 83 reptile taxa were collected during this expedition – approximately half of them described by J. G. Wagler – but currently specimens of only 53 taxa are still present in Munich. Subsequently, herpetological research in South America was continued during the fi rst half of the 20th Century by L. Müller und W. Hellmich, who deposited primary type material of 95 reptile taxa (49 from South America, among them 26 of the iguanid genus Liolaemus) in the ZSM, 47 of them still represented by primary types. Another geographical focus of the reptile type collection is the Mediterranean area, the Macaronesian region and the Middle East with a total of 46 extant primary types. Herpetological research in this area dates back to descriptions by G. Jan in 1863 and was continued by L. Müller, H. H. Schleich, A. Beutler, and especially J. F. Schmidtler and their respective collaborators.

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Double mutualism (DM) is a recently observed and considered phenomenon in ecology, in which a same animal species pollinates and disperses a same plant species. Very few DMs have still been reported, and little is known about their occurrence and species involved. Generalist and opportunist animal species, which have broad diet niches and sometimes act as efficient pollinators and seed dispersers, might be particularly good candidates to stablish double interactions, as they more likely may consume nectar, pollen and fruits of a same plant. Still little information exists, however, about their effectiveness compared to specialised species. This thesis aims to improve knowledge on the novel phenomenon of double mutualism, paying special attention on the importance of opportunistic nectarivores. Specifically, the thesis has three main research questions: Where DMs are more frequent and which are the taxa mainly involved in them (chapter 1)? We conducted a systematic review of published and unpublished data to provide geographical, taxonomical and ecological baseline information for future research on DMs. Most DMs occur in tropical and island ecosystems, involving mainly opportunistic vertebrate nectar consumers and generalist plants. Moreover, nearly 30 % of the species involved in DMs are threatened. High prevalence of DMs on islands and their vulnerability suggest that many DMs are also threatened with still unknown consequences for the maintenance of community composition and ecosystem functioning. How important opportunistic animals can be as double mutualists (chapters 2 - 3)? We analysed the role of a nectar-opportunist lizard (Podarcis lilfordi) who visits the flowers and consumes the fruits of the plants Ephedra fragilis and Cneorum tricoccon. Given that conspecific individuals may have different potential roles in pollination and seed dispersal, and, thus may have different consequences for plant success, intraspecific variation was integrated in the observational work and analyses. Our results show that P. lilfordi acted as an effective double mutualist, however, lizards were differently involved in both pollination and seed dispersal. On E. fragilis, adult lizards were the most involved; but, on C. tricoccon female and juveniles were the main nectar consumers, and consequently pollinators, while males were the main fruit consumers and seed dispersers. Our results support the hypothesis that intraspecific differences in mutualistic species constitute important differences which may result in different mutualistic roles. Thus, studies performed at the species level might mask the real function of intraspecific groups and/or individuals on mutualistic interactions. How important nectarivore opportunist vertebrates can be relative to specialists and insects (chapter 4)? We measured and compared pollination effectiveness (PE) of vertebrate and insect pollinators of three plant species in the Seychelles archipelago (Thespesia populnea, Polyscias crassa and Syzygium wrightii), measuring quantity and quality components. Our study indicates that some Seychelles plant species depend on insects and specialised vertebrate pollinators, but also on opportunistic vertebrate nectar-feeders. The data on T. populnea and S. wrightii supported the hypothesis that specialist nectar feeders have higher PE than opportunistic nectar-feeding species; by contrast, the generalist geckos were more effective pollinators than specialist animals on P. crassa. Furthermore, we showed that PE of a particular pollinator species varies depending on the plant species, regardless of its feeding behaviour. Results also highlight the vulnerability of pollination interactions to invasive alien species, as the ABSTRACT 28 PE of vertebrate pollinators was compromised by the presence of the invasive yellow crazy ant, Anoplolepis gracilipes, which primarily reduced their flower visitation rates. This thesis contributes with a wide picture of DMs around the World, and with some analysed examples. It also underlines that measuring effectiveness of interactions and their components is important and need to be integrated in mutualistic studies, as well as focus such studies at intraspecific level, otherwise the real function of each intraspecific group is masked. We hope that this thesis is the beginning of a change in the way of perceiving and studying mutualisms and, in general, ecological interactions.

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An increasing number of double mutualisms (i.e. two interacting species benefiting each other in two different functions, e.g. pollination and seed dispersal) have been reported, mainly from island ecosystems, although we still lack much information on how effective such species are in both processes. Here, we assessed the pollination effectiveness of a double mutualism between an ancient Mediterranean gymnosperm, Ephedra fragilis Desf., and a lizard, Podarcis lilfordi L. On the one hand, we assessed the lizard contribution to different fitness measures (seed set and germination success), relative to that of insects and the wind effect; on the other, we determined the lizards’ seed removal rate (i.e. the quantity component of seed dispersal effectiveness). In both processes, we further tested for differences in their contributions among male, female and juvenile lizards. Ephedra fragilis showed to be mostly anemophilous, lizards and insects playing only a minor role on seed set. However, lizards qualitatively contributed to pollination success, as seeds coming from lizard-pollinated cones germinated at higher rates than those pollinated by wind or insects, although this was detected only for small seeds (<8mg). The plant produced a low seed set (c. 23%), which was compensated by a high seed germinability (c. 70%). Adult male lizards were those most implicated in pollination, quantitatively more important than insects, and in seed dispersal. This work, thus, reports the importance of a lizard species in one of the few double mutualisms found in the world involving a gymnosperm, and it represents the first documentation of a double mutualism in the Mediterranean region. Our findings further contribute to highlight the role of both inter- and intra-specific differences in the effectiveness of mutualistic interactions.

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Although most plants depend on different animals for pollination and seed dispersal, sometimes the same animal species provides both functions, being thus involved in what has been termed a ‘double mutualism’. Very little is known on the effectiveness of such species as both pollinators and seed dispersers, and even less on the intraspecific level differences at the contribution of an animal mutualist to plant fitness. In this study, we focused on the interaction between a Mediterranean shrub Cneorum tricoccon (Rutaceae) and the Balearic lizard Podarcis lilfordi (Lacertidae) in order to assess: 1) the role of this lizard as a legitimate pollinator of the plant (previously thought to be exclusively insect‐pollinated), and 2) the intraspecific variation in the use of flowers and fruits by lizard individuals, comparing males, females and juveniles. We further evaluated whether lizards show different fruit size selection depending on sex and age, with potential consequences for seed germination. Lizards visited more flowers and selected more hermaphrodite flowers than insects did, leading to relative increases in both fruit and seed set. Interestingly, female and juvenile lizards were the main flower visitors, whereas males were the main fruit consumers. Males selected the largest fruits (bearing the largest seeds) though this did not increase seed germination, which was only ca 15%. We concluded that P. lilfordi acts as a legitimate pollinator of C. tricoccon and, thus, confirm that this system constitutes a new case of double mutualism, especially common in island compared to mainland systems. Moreover, our findings show a large variation among conspecific individuals in their role as either pollinators or seed dispersers, with potential implications for plant reproductive success. Our study, therefore, highlights the importance of evaluating plant–animal interactions at the intraspecific level, and calls for more in‐depth studies on the consequences of such intraspecific variation.

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A first complete list of the reptile type specimens preserved in the Museo Nacional de Ciencias Naturales (CSIC) of Ma-drid (updated until 15 July 2012) is provided. The collection houses a total of 319 type specimens representing 24 taxa belonging to 6 families and 12 genera. There are 22 taxa represented by primary types (19 holotypes, 2 neotypes and 1 lectotype) and at least one paratype, and only two taxa are exclusively represented by one secondary type (paratype). The collection is specially rich in Spanish endemisms. Special attention is deserved by the type series of many subspecies of Podarcis lilfordi described by A. Salvador and V. Pérez-Mellado. All type specimens are housed in the Herpetological collection except Blanus mariae and Psammodromus occidentalis type series and Psammodromus hispanicus (neotype) which are preserved in the DNA/Tissues Collection.

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The aim of this study is to assess the health status of different populations of P. lilfordi, an endemic lizard of the Balearic Islands. The health status and potential environmental stress to which these populations are subject estimaatendiendo four independent indicators, putting both to test its reliability and searching for the possible relationship between them. These four indicators are: the so-called state of condition of individuals, the parasite load, immune response and the degree of fluctuating asymmetry observed in bilateral characters. Also, relationships are established with adaptive responses in terms of features of behavioral ecology, including: strategies to secure food, defense capabilities and tactics of escape from predators.

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Parasites are important in understanding population dynamics and ecology of hosts. In several Mediterranean islands, little is known about lizards’ blood parasites. We studied the relations between haemoparasites and an endemic lizard host, Podarcis lilfordi (Günther, 1874) on Aire Island (Menorca, Balearic Islands, Spain). The infection intensity was about 1% of the red blood cells and 95% of the individuals were infected. These values are higher than in continental populations of the genus Podarcis. The reduced genetic variability and/or the high density in islands are proposed to explain such differences. More adults than juveniles were infected, probably because they were more often exposed to parasites during their lifetime. In adult lizards, prevalence was higher in males, may be as a consequence of their higher activity levels and more frequent physical contacts during male–male interactions. We found that infected individuals were larger than uninfected ones. A higher prevalence in adults is responsible of these differences. The intensity of infection was similar between age and sex classes. Prevalence remains stable between seasons, while parasite load increases in summer, as the availability of resources and body condition decreases. We found a relation between prevalence, intensity and body condition, with a higher prevalence and parasite load in individuals with lower condition.

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The spatial distribution of a population of lizards is influenced by the distribution of resources and the individuals’ skills to gain access to them. On several Mediterranean islands with food scarcity and unpredictable resource availability, some resources can be extremely important during some periods of the year, as, e.g., the dead horse arum, Dracunculus muscivorus, on Aire Island, Spain. In this study, we analysed parasite infestation in an endemic lizard, Podarcis lilfordi, in relation to the distribution of D. muscivorus during spring. We found a higher prevalence of parasitism in males from a central area where the plant was significantly more abundant. Also, in this area, males were more abundant and larger than in two areas with lower plant densities. Moreover, overall differences appeared in the intensity of infection, which was higher in individuals from the central area, and we found a relationship between body size and parasite load, with more infected cells in larger individuals. Spatial distribution of individuals due to differential availabilities of D. muscivorus is proposed as an explanation for the observed differences.

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Parasites are able to negatively affect the locomotor performance of their hosts, and consequently, their biological fitness. In this study, we examine the relationship between parasitism and burst speed in an insular population of Lilford’s Wall Lizard (Podarcis lilfordi (Günther, 1874)). Podarcis lilfordi is normally infected with haemogregarine blood parasites and mites in our study location, Aire Island (Balearic Islands, Spain). Unlike the results from other studies on lizards, we found a significant negative correlation between intensity of infection by haemogregarines and burst speed. Body condition is also significantly related to burst speed. Thus, lizards with a lower blood parasite load and better body condition show a faster sprint speed. Intensity of infection by haemoparasites shows a lack of correlation with both body condition and mite load. Our results are compared with those from other lizard species living in different habitats. We discuss the influence of insular environmental conditions on locomotor performances, such as low predation pressure, lack of competitors, and high lizard densities

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In animals, developmental stability is frequently assessed by the level of fluctuating asymmetry. Several environmental and genetic stress factors can increase the developmental instability in a population. Anyhow, the use of fluctuating asymmetry as a measurement of developmental instability and its relationship to other measurements of genetic and environmental stress, remain controversial. We studied this subject in the Balearic lizard, Podarcis lilfordi, and examined four populations inhabiting different coastal islets of Minorca (Balearic Islands, Spain). These populations show clear ecological and genetic differences that allowed us to study factors potentially determining the level of fluctuating asymmetry. We examined the following predictions: (1) fluctuating asymmetry will increase on smaller islands; (2) fluctuating asymmetry will increase on islands with a higher lizard density; (3) fluctuating asymmetry will increase on islands with more heavily parasitized lizards; and (4) populations with higher inbreeding levels would be more susceptible to environmental stress. Our results would partially support the fourth prediction of a higher fluctuating asymmetry in populations with lower genetic variability and, consequently, a higher inbreeding level. Probably, other environmental factors modulate this relationship.

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Many wild populations of lizards in the Mediterranean Basin inhabit small islands frequently visited by humans. Reptiles respond to humans as potential predators by escaping to refuges or by increasing antipredator behaviours which lead to a loss of body condition and may have important consequences for fitness. We assessed effects of human pressure on parasitism and body condition of the endangered insular lizard Podarcis lilfordi in Aire Island (Balearic Islands, Spain). Two areas differing in the number of visitors were compared at different seasons: spring, with almost no human pressure, and summer, when the major bulk of visitors arrive. Compared across seasons, the lizards from areas frequented by humans suffered a greater loss of body condition and showed a less parasitism reduction compared to individuals from the undisturbed area. Therefore, human disturbance seems to have deleterious effects on body condition and other fitness-related drivers, as parasitism. Results evidence important consequences of tourism for short- and long-term fitness of individuals and should be considered when designing conservation plans or management strategies.

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Economic escape models predict escape decisions of prey which are approached by predators. Flight initiation distance (FID, predator–prey distance when prey begins to flee) and distance fled (DF) are major variables used to characterize escape responses. In optimal escape theory, FID increases as cost of not fleeing also increases. Moreover, FID decreases as cost of fleeing increases, due to lost opportunities to perform activities that may increase fitness. Finally, FID further increases as the prey`s fitness increases. Some factors, including parasitism, may affect more than one of these predictors of FID. Initially, parasitized prey may have lower fitness as well as impaired locomotor ability, which would avoid predation and/or reduce their foraging ability, further decreasing the opportunity of fleeing. For example, if parasites decrease body condition, prey fitness is reduced and escape ability may be impaired. Hence, the overall influence of parasitism on FID is difficult to predict. We examined relationships between escape decisions and different traits: parasite load, body size and body condition in the Balearic lizard, Podarcis lilfordi. Lizards that showed higher haemogregarines load had longer FID and shorter DF. Although results did not confirm our initial predictions made on the basis of optimal escape theory, our findings suggest that parasites can alter several aspects of escape behaviour in a complex way.

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From childhood to adulthood we receive a lot of information on animal key species with a high charismatic value. Flagships species are also frequently used to raise awareness, stimulate conservation and to increase political support for conservation issues. Since flagship species do not, in many cases, represent the local ecological community, there is the risk that exotic species are more readily identified than local ones and this could be problematic, as knowledge is critical to promote conservation. Conservation is especially crucial on islands, where populations may be more prone to extinctions than in the mainland, and where isolation may favor endemism. To test the hypothesis that exotic species are better known than local ones, we surveyed high school children in the Balearic Islands, a biodiversity hot spot for conservation priorities. We quantified children’s knowledge of native and exotic vertebrate groups by using a computer-aided multiple choices questionnaire. We found that exotic species are better known than local fauna, even when local fauna is broadly common or of greater conservation concern. We also found strong differences in knowledge between different vertebrate groups: the best known were mammals whereas fishes were the least known. Surprisingly, even if less known than mammals, local amphibians and reptiles were better known than exotic ones. Children’s poor knowledge on the local fauna in relation to other exotic vertebrates may lead them to associate wildlife and its conservation with exotic species. We suggest increasing efforts on environmental education and focussing on direct experience of children in their local environment to increase their knowledge of the local fauna, and engage their interest in their own natural world.

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This paper reviews the ecological literature published during the last 15 years on pollination and seed dispersal by lizards, in order to determine the possible effects of these animals on plant reproduction. This review is only limited to these years because articles on plant-lizard interactions during this period have used more rigorous experimental approaches than those made previously. All compiled data were analyzed considering the conceptual framework provided by the quantity and quality components of pollination and seed dispersal (i.e., effectiveness), since this information is essential to have an idea of the relative contribution of animals to plant fitness. Results showed that 34 species of lizards feed on nectar and fruits of plants. While lizards consume these plant materials, they could effectively pollinate flowers or disperse seeds to sites away from parent plants. However, more studies on particular aspects of these interactions should be conducted in order to completely understand the ecological and evolutionary effects of lizards on plants.

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In recent years there has been an exponential increase in the amount of published DNA sequences, as it has become one of the most popular sources of data for reconstructing phylogenies. A number of studies have attempted to resolve the relationships of groups of lacertids using mitochondrial DNA sequence data, in particular Podarcis and Gallotia (e.g. THORPE et al., 1994; 1996; GONZALEZ et al., 1996; FU et al., 1997; HARRIS, 1997; HARRIS et al., 1998a; 1999; CASTILLA et al., 1999a,b). Reassessment of these data suggest some alternative phylogenies to those previously published, and also highlight possible problems. Two studies have attempted to unravel the phylogeny of the whole family using mitochondrial DNA sequences (FU, 1998; HARRIS et al., 1998b). By combining these essentially congruent data sets, and reanalysing levels of support for the phylogenies produced, a more complete estimate of relationships across the family is produced. This is then compared to alternative sources of evidence, primarily morphological (ARNOLD, 1989), biochemical (MAYER & BENYR, 1994) and karyological (OLMO et al., 1993). Reasons for discrepencies are discussed, as are the relative advantages and disadvantages of the different sources of phylogenetic inference.

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Mitochondrial DNA sequence data support conclusions based on morphology, that Podarcis is a clade and is derived from the paraphyletic genus Lacerta, its immediate outgroups being Lacerta andreanszkyi and then the sister species L. perspicillata and L. dugesii. Within Podarcis, there are four geographically coherent clades: the Western island group-filfolensis (lilfordi, pityusensis), tiliguerta; the Balkan group-[(melisellensis, taurica) (gaigeae, milenis) and perhaps wagleriana and (erhardii, peloponnesiaca)]; the Italian group-sicula, (raffonei, muralis); and the Southwestern group-(atrata, bocagei), hispanica.

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DNA sequences from parts of the 12S, 16S and cytochrome b mitochondrial genes, which totalled 1049 aligned base pairs, were used to estimate the relationships of 49 species of Lacertidae, including representatives of 19 out of the 23 recognized genera and 23 species of the paraphyletic genus Lacerta. These data were used, together with morphological information, to estimate the relationships within the family. Molecular evidence corroborates the monophyletic status of many genera and species groups originally based on morphology. It indicates that Psammodromus forms a clade with Gallotia, which is the sister taxon of all other lacertids. These comprise three units: the primarily Afrotropical armatured group; the largely Oriental Takydromus; and the west Palaearctic Lacerta and its derivatives, Podarcis and Algyroides. Morphology also supports the first three assemblages, but suggests that they are derived from a paraphyletic Lacerta. Within Lacerta and its allies, DNA sequence analysis corroborates the affinity of some members of each of the subgenera Lacerta s. str. and Timon, and of the L. saxicola group. It also supports the relationship of L. monticola, L. bonnali and L. horvathi, and suggests that the L. parva–L. fraasi clade and L. brandti are not related to Psammodromus–Gallotia, as morphology indicates, but instead are associated respectively with the L. danfordi and L. saxicola groups. DNA sequence data provide additional evidence that the eastern Arabian `Lacerta` jayakari and `L.` cyanura are members of the armatured clade and also sister species. Our analysis supports an origin for present lacertids in west Eurasia. The armatured clade invaded Africa, probably in the mid-Miocene, spreading widely and evolving increasingly xeric-adapted forms, one lineage of which later moved back into the Palaearctic. `Lacerta` jayakari and `L.` cyanura are assigned to Omanosaura, Lutz and Mayer 1986. The name Gallotiinae Cano, Baez, Lopez-Jurado and Ortega, 1984 is available for the Gallotia–Psammodromus clade, Eremiainae Shcherbak 1975 for the armatured clade and Lacertinae for Lacerta, Podarcis and Algyroides. Two new subgenera of Lacerta are proposed here: Caucasilacerta for L. saxicola and its allies, and Parvilacerta for L. parva and L. fraasi.

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The occurrence of Apicomplexan parasites in Podarcis wall lizards from the Iberian Peninsula and Balearic islands was studied by amplification and sequencing of the 18S rRNA gene. Species from three genera, Hepatozoon, Sarcocystis and Eimeria were detected. The phylogenetic analysis of the 18S rRNA gene provides unexpected insights into the evolutionary history of these parasites. All Hepatozoon specimens were recovered as part of a clade already identified in lizards from North Africa. The Sarcocystis species, detected in Podarcis lilfordi from Cabrera island, in the Balearic Islands, appears related to Sarcocystis gallotiae, known only from endemic Gallotia lizards from the Canary Islands. Based on the lack of snake predators on this island, this parasite form presumably presents an atypical transmission cycle that uses the same host species as both intermediate and final host through cannibalism, like S. gallotiae. Eimeria is reported for the first time from Podarcis lizards. This study shows the power of detecting multiple different Apicomplexa parasites through screening of tail tissue samples and blood drops that are often collected in reptiles for other purposes.

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Conclusions Podarcis tiliguerta appears to be a species complex. Further morphological and molecular analyses will be needed to confirm this. Podarcis sicula is not sister taxon to P. muralis, nor is P. wagleriana a genetic lineage within P. filfolensis as has been previously suggested. However relationships between most Podarcis species remain unresolved.

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scape theory predicts that a prey should start escaping (flight initiation distance = FID) from a predator when the costs of fleeing and the cost staying are equal or until future fitness is maximized. Consequently, prey escape performances and current reproductive asset can affect FID. We tested effects of body condition, morphology, and whether the tail was regenerated or original on FID in the Balearic lizard (Podarcis lilfordi) by ourselves simulating predators. Lizards with better body condition had longer FID and lizards with longer intact tails had shorter FID. Lizards with regenerated tail presented shorter FID than lizards with intact tails. These results suggest that impaired escape performance is counterbalanced by fitness costs of tail regeneration or by alteration of escape behaviour. The weak association between morphology, body condition and FID suggest that escape performances and asset protection have relatively small effect on P. lilfordi escape decisions.

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Feeding specializations such as herbivory are an often cited example of convergent and adaptive evolution. However, some groups such as lizards appear constrained in the evolution of morphological specializations associated with specialized diets. Here we examine whether the inclusion of plant matter into the diet of omnivorous lacertid lizards has resulted in morphological specializations and whether these specializations reflect biomechanical compromises as expected if omnivores are constrained by functional trade-offs. We examined external head shape, skull shape, tooth structure, intestinal tract length and bite performance as previous studies have suggested correlations between the inclusion of plants into the diet and these traits. Our data show that omnivorous lacertid lizards possess modifications of these traits that allow them to successfully exploit plant material as a food source. Conversely, few indications of a compromise phenotype could be detected, suggesting that the evolution towards herbivory is only mildly constrained by functional tradeoffs.

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Invasive species currently account for a major threat to global biodiversity, and island ecosystems are among the most vulnerable, because of the frequency and success of species introductions on islands. Within Mediterranean islands, reptiles not only are frequently introduced species but are also among the most threatened because of these introductions. The Balearic archipelago is a good example of this, since only two of its current 16 species of reptiles are native. Thirteen years ago, the snake Hemorrhois hippocrepis was introduced by cargo in Ibiza island, and it is in expansion. Individuals obtained from an early eradication campaign showed a fast expression of phenotypic plasticity and acquired larger sizes than those of the source population, probably due to a high prey availability and predator scarcity. The species is thriving at the expense of a small variety of native and non-native prey, but the predation pressure on the endemic Podarcis pityusensis, the only native reptile in the island, is very high, as this lizard represents 56% of the prey in frequency, which might threaten its survival on the long term. Our results on the feeding ecology of the snake are of sufficient concern to justify the maintenance of actions to eradicate this invader.

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A survey about the helminthfauna of Podarcis lilfordi (Günther, 1874) (Sauria, Lacertidae) in the Gimnesic Islands (Balearic Islands, Spain) has been carried out. Eleven species of helminths were found, two Digenea, eight Nematoda and one Acanthocephala. Data of prevalence of each helminth species are indicated. The nematodes Skrjabinodon medinae and Spauligodon cabrerae show the highest values of prevalence and abundance. Host-parasite relationships are discussed, and the absence of cestodes is pointed out.

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The life and work of the Alsatian Louis Amédée Lantz (1886-1953), a pioneer of European herpetology. A trained and professional research-chemist, the Alsatian Louis Amédée Lantz was an active and particularly dynamic herpetologist. His residence of nearly twelve years in Russia enabled him to make several field trips to regions such as the Caucasus and Iran. He always carried with him a home made telescopic net that he used to catch lizards. That net became symbolic of Lantz for most people around him. He realized significant herpetological collections mainly deposited in the Museum of the Zoology Institute of the Russian Academy of Sciences in St. Petersburg. Soon after the Russian Revolution in 1917, he had to leave the country and stayed for a few years in France before joining England. During this period, Lantz visited the French Pyrenees and the Mediterranean border (Hyeres Islands, Bandol), enabling him to discover for the first time oviparous populations of common lizard and also to describe a new species of lizard from the French Pyrenees. Lantz is also at the origin of the discovery of unisexual reproduction by parthenogenesis in reptiles. His collaboration with the Swedish amateur herpetologist Otto Cyrén, whom he met through the German herpetologist Willy Wolterstorff, was particularly successful throughout his career. Lantz died at the age of 66 years, in Switzerland, as he was about to join the team of herpetologists at the Natural History Museum in Paris.

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Dans cette note on étudie les squamates du Pliocene, Pléistocene et Holo- cene des Baléares. Mallorca et Menorca ont été envahies vraisemblemblement pendant le Miocene supérieur par uné espece du genre Lacerta. Mallorca pendant le passage Plio-Pléis- tocene est peuplée par une population de lézards qui anoncent déja l`espece actuelle (Lacer- ta (Pordareis) afi. lilfordi). Les gisements du Pléistocene supérieur et de I`Holocene ont li- vré restes de l`espece vivante Lacerta (Podareis) lilfordi qui est disparue actuellement de cette ile et aussi de Menorca (oú on a trouvé aussi des restes holocenes de la meme espece) et occupe seulement des ilots aux voisinages de deux iles majeures. La population holocene de la Cova de Muleta (Mallorca) présente des particularités (taille plus robuste, nombre des dents plus élevé soit sur le maxillaire soit sur le dentaire) qui permettent sa séparation au niveau subspécifique, Lacerta (Pordacis) lilfordi muletensis ssp. n. Quelques rares restes du Pléistocene inférieur de Menorca sont classifiés comme Lacerta (Podareis) sp. La disparition de Lacerta lilfordi de Mallorca et Menorca est due probablement a l`introduction de ser- pents dans les iles de la part de l`homme. Enfin un stock des lézards baléariques a envahi probablement pendant le Pliocene ou le Pléistocene, Eivissa et les ilots voisins et a donné naissance a Lacerta (Pordacis) pityusensis.

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Experimental studies about any species could not be carried out without a solid foundation about its biology and natural history. However, a great amount of time, energy and perseverance are recquired in order to collect these data, especially in long-term studies at individual level. This kind of studies monitor individually recognisable animals, which allows to get repeated measures of the studied traits. Thus, access to enough numbers of recognisable individuals with known life histories provides the possibility of asking, and answering, a wide range of novel questions that are otherwise inaccesible, allowing to conduct statistical analyses and/or experiments that isolate the effect of particular traits, impossible to perform on a sample of unknown individuals. In this thesis, we aim to know in a precise way the life-history traits of a population of Lilford’s wall lizard, Podarcis lilfordi, as well as its dynamic at individual level. To do so, a capture-recapture study spanning three years from April to September was carried out on an experimental plot. During the study period, information about several aspects of the lizards’ natural history, such as their home ranges, their coloration and seasonal variability, the traits of sexual dimorphism and their pairing patterns, was gathered. Through the use of these data the influence of such individual traits on intraespecific interactions and thus, their effect on dominance, will be stablished. General results show that the studied population of Lilford’s wall lizard moves around small-sized home ranges, to which individuals are faithful. The value given to said home ranges decides the outcome of aggresive interactions among neighbours invariably favoring the residents of the home range. Additionally, reduced aggression between neighbours is observed. However, when residency factor is nonexistent, dorsal coloration predicts the outcome of male contests, much more colourful than females. Nevertheless, both sexes manifest seasonal change in their dorsal coloration, although for different reasons. Evidences for mate guarding, as well as remarkable fidelity among observed pairs, were also found during mating season. Lastly, dominance is subject to mate choice and, in females only, mate dominance appears as the only significative factor regarding females own dominance.

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The genus Hepatozoon Miller, 1908 (Apicomplexa: Adeleorina) is composed of intracellular haemogregarine parasites that are widely distributed among all tetrapod groups. The present study combines microscopic and molecular data on haemogregarine parasites from lizards in the western Mediterranean. We screened tissue samples and examined blood smears for the presence of species of Hepatozoon from four lizards, namely Algyroides marchi Valverde, endemic to Southeast Spain, Podarcis bocagei Seoane from Spain and Portugal, P hispanica Steindachner from Spain, and P lilfordi Günther from Cabrera, Balearic Islands (Spain). Our results show that prevalence and intensity of Hepatozoon parasites vary between and within lizard species from different regions. Algyroides marchi and P bocagei from Spain had the lowest values, whereas P hispanica had the highest. Phylogeny based on 18S rRNA gene sequences indicates that most of the new Hepatozoon sequences are part of a clade exclusive from North African and Iberian lizards, except for a single P bocagei isolate that is found related to another clade including isolates from other reptile host species and rodents. Interestingly, isolates from Algyroides form a distinct monophyletic subgroup, which could be a signal of strict host-specificity within this host genus.

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Many lizards use femoral gland secretions in intraspecific communication. Although there is a consistent interspecific variation in chemical composition of secretions, considerable variation is also often found between populations, which may affect conspecifc recognition and lead to speciation processes. Balearic lizards (Podarcis lilfordi) are currently distributed only in several isolated islets offshore of the main islands with different environmental conditions (vegetation, diet, density of population, etc). Also, there is a high genetic variability between populations. We examined whether there was a similar variation in the composition of the femoral secretions of male lizards, and which could be the causes of such variation. By using GC–MS analyses, we found 75 lipophilic compounds in femoral gland secretions of male P. lilfordi from three representative island populations. Main compounds were steroids (94.4%), mainly cholesterol, but we also found alkanes, ketones, waxy esters, squalene, carboxylic acids and their ethyl esters, alcohols and other minor compounds. However, there were clear differences between populations with respect to the number and relative proportions of compounds. Using the patterns of presence and abundance of compounds in secretions it is possible to predict the population of origin of a lizard. We discuss how these differences could be explained considering genetic and environmental differences between populations.

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The arrival to the Balearic Islands of new species proceeding from the Iberian Peninsula and other peri-mediterrnean regions supposes a potential threat for the survival of the two endemic lacertids. The accession and rapid expansion of Hemorrhois hippocrepis and Rhinechis scalaris in Ibiza, an island without snakes until a few years ago, might already be affecting the populations of Podarcis pytiusensis. The populations of Podarcis lilfordi on Cabrera and the other islets sur- rounding Majorca might equally in turn be affected by Podarcis siculus, another lacertid species recently introduced in Mallorca.

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Three subspecies of P. lilfordi were observed in their natural habitats. Some fieldnotes and notes on behaviour in captivity are given. Finally it is stated that these three subspecies appear not to be endangered.

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Se ha realizado un estudio ultraestructural sobre la pared quistica de Sarcocystis dugesii, localizado en el musculo estriado de las extremidades posteriores de Podarcis lilfordi. El quiste posee forma ovoide y su pared quistica primaria forma largas protusiones digitiformes. Debido posiblemente a la implantacion del quiste en el musculo, desorganizacion de las miofibrillas, alteracion mitocondrial y presencia de vacuolas. En algunas ocasiones se ha puesto de manifiesto la presencia de haces nerviosos de fibras mielinicas con una marcada alteracion de naturaleza degenerativa. Estos haces nerviosos se localizan cerca del paquete muscular en donde se implanta el quiste. La pared quistica secundaria no ha sido observada.

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Summary of bio-invasions on the Balearic Islands. The endemic lizard from Mallorca and Minorca, Podarcis lilfordi, has been extirpated from the main islands and only survives on islets that have remained free of snakes and carnivores. In addition, the Mallorcan midwife toad, Alytes muletensis only survives in thefew karst canyons.

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Available data regarding conservation status of lizard populations from Balearic Islands, as well as threat factors affecting them are presented. Some populations are highly threatened, due to their intrinsic limitation of island surface occupied and, in addition, there are cases of viable artificial populations. Hence, we propose the translocation of most threatened populations to islets today unoccupied by lizards. We show the critria under which such operation could be performed.

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Endemic lizards from Balearic Islands, Podarcis pityusensis and P. lilfordi, are subjected to legal protection and effective conservation measures in recent decades. Since Martínez-Rica and Cirer (1982) –a paper devoted to the pityusic species, but that would be generalized-, the situation has changed considerably. In this communication, we consider the current legal situation, the habitats what are covered by protected areas (natural parks and reserves), and the factors of threat sug- gested recently. Finally, we enumerate the priorities in the future management of both species -according to the authors-, and which stocks would be those of preferential attention.

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Aim Body size is instrumental in influencing animal physiology, morphology, ecology and evolution, as well as extinction risk. I examine several hypotheses regarding the influence of body size on lizard evolution and extinction risk, assessing whether body size influences, or is influenced by, species richness, herbivory, island dwelling and extinction risk. Location World-wide. Methods I used literature data and measurements of museum and live specimens to estimate lizard body size distributions. Results I obtained body size data for 99% of the world`s lizard species. The body size–frequency distribution is highly modal and right skewed and similar distributions characterize most lizard families and lizard assemblages across biogeographical realms. There is a strong negative correlation between mean body size within families and species richness. Herbivorous lizards are larger than omnivorous and carnivorous ones, and aquatic lizards are larger than non-aquatic species. Diurnal activity is associated with small body size. Insular lizards tend towards both extremes of the size spectrum. Extinction risk increases with body size of species for which risk has been assessed. Main conclusions Small size seems to promote fast diversification of disparate body plans. The absence of mammalian predators allows insular lizards to attain larger body sizes by means of release from predation and allows them to evolve into the top predator niche. Island living also promotes a high frequency of herbivory, which is also associated with large size. Aquatic and nocturnal lizards probably evolve large size because of thermal constraints. The association between large size and high extinction risk, however, probably reflects a bias in the species in which risk has been studied.

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Aim Temperature influences most components of animal ecology and life history – but what kind of temperature? Physiologists usually examine the influence of body temperatures, while biogeographers and macroecologists tend to focus on environmental temperatures. We aim to examine the relationship between these two measures, to determine the factors that affect lizard body temperatures and to test the effect of both temperature measures on lizard life history. Location World-wide. Methods We used a large (861 species) global dataset of lizard body temperatures, and the mean annual temperatures across their geographic ranges to examine the relationships between body and mean annual temperatures.We then examined factors influencing body temperatures, and tested for the influence of both on ecological and life-history traits while accounting for the influence of shared ancestry. Results Body temperatures and mean annual temperatures are uncorrelated. However, accounting for activity time (nocturnal species have low body temperatures), use of space (fossorial and semi-aquatic species are ‘colder’), insularity (mainland species are ‘hotter’) and phylogeny, the two temperatures are positively correlated. High body temperatures are only associated with larger hatchlings and increased rates of biomass production. Annual temperatures are positively correlated with clutch frequency and annual longevity, and negatively correlated with clutch size, age at first reproduction and longevity. Main conclusions Lizards with low body temperatures do not seem to have ‘slower’ life-history attributes than species with high body temperatures. The longer seasons prevalent in warm regions, and physiological processes that operate while lizards are inactive (but warm enough), make environmental temperatures better predictors of lizard life-history variation than body temperatures. This surprisingly greater effect of environmental temperatures on lizard life histories hints that global warming may have a profound influence on lizard ecology and evolution.

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Antipredatory defenses are maintained when benefit exceeds cost. A weak predation pressure may lead insular lizards to tameness. Podarcis lilfordi exhibits a high degree of insular tameness, which may explain its extinction from the main island of Menorca when humans introduced predators. There are three species of lizards in Menorca: the native P. lilfordi, only on the surrounding islets, and two introduced lizards in the main island, Scelarcis perspicillata and Podarcis siculus. In addition, there are three species of snakes, all introduced: one non-saurophagous (Natrix maura), one potentially non-saurophagous (Rhinechis scalaris) and one saurophagous (Macroprotodon mauritani-cus). We studied the reaction to snake chemical cues in five populations: (1) P. lilfordi of Colom, (2) P. lilfordi of Aire, (3) P. lilfordi of Binicodrell, (4) S. perspicillata, and (5) P. siculus, ordered by increasing level of predation pressure. The three snakes are present in the main island, while only R. scalaris is present in Colom islet, Aire and Binicodrell being snake-free islets. We aimed to assess the relationship between predation pressure and the degree of insular tameness regarding scent recognition. We hypothesized that P. lilfordi should show the highest degree of tameness, S. perspicillata should show intermediate responses, and P. siculus should show the highest wariness. Results are clear: neither P. lilfordi nor S. perspicillata recognize any of the snakes, while P. siculus recognizes the scent of M. mauritanicus and reacts to it with typical well-defined antipredatory behaviours as tail waving and slow motion. These results rise questions about the loss of chemical recognition of predators during island tameness and its related costs and benefits for lizards of insular habitats. In addition, this highlights the necessity for strong conservation measures to avoid the introduction of alien predators.

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Conclusión Más allá de la explicación de la distribución de las áreas relevantes de biodiversidad, donde intervienen procesos ecológicos y evolutivos, creemos que estudios como éste pueden ayudar a la identificación de zonas del territorio especialmente valiosas para la conservación de la biodiversidad. En lugares donde no existe tiempo ni recursos económicos para llevar a cabo análisis exhaustivos de la biodiversidad, sugerimos que una estrategia basada en el criterio del índice combinado puede proveer la adecuada protección para muchos grupos de organismos. La coincidencia entre áreas relevantes de diversidad de anfibios y reptiles y la red de ENPs en España peninsular y Baleares deja unos huecos que deben ser corregidos. Los mapas producidos constituyen una herramienta valiosa para el establecimiento de nuevos espacios protegidos, prevención del impacto ambiental y restauración de ecosistemas.

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Unique body characteristics are increasingly used for individual recognition to avoid the effort and the potential negative effects of capture–mark–recapture technique.As a consequence there is a growing demand for computer procedures to assist users in photo-recognition of an individual. We present a new software for photo-matching developed to minimize the pre-processing time and maximize the speed of the matching procedure. In APHIS photos can be processed in batches of hundreds and users can select between two alternative matching procedures, one interactive, built as an extension of existing and freely available software, and one automatic. We assessed its performance in terms of individual recognition and time efficiency and illustrate its use with real capture-photo–recapture studies on a reptile and an amphibian species, the Balearic Lizard Podiarcis lilfordi and the Northern spectacled salamander Salamandrina perspicillata, with contrasting skin patterns.

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The accelerating rate of vertebrate extinctions and population declines threatens to disrupt important ecological interactions, altering key ecosystem processes such as animal seed dispersal. The study of highly specialized mutualistic interactions is crucial to predict the consequences of population declines and extinctions. Islands offer unique opportunities to study highly specialized interactions, as they often have naturally depauperated faunas and are experiencing high rates of human-driven extinctions. In this study, we assess the effect of seed dispersal on seedling recruitment of Ephedra fragilis (Ephedraceae) on a Mediterranean island ecosystem. We used field data and stochastic simulation modeling to estimate seed fate and recruitment patterns of this pioneer shrub typical of arid and semiarid areas, and to estimate the dependence of recruitment on the lizard Podarcis lilfordi (Lacertidae), its only known seed disperser. Ephedra fragilis recruitment highly depended on lizards: lizards produced 3.8 times more newly-emerged seedlings than non-dispersed seeds and no seedlings from undispersed seeds survived the study period. Seed dispersal by lizards was mostly to open sites, which was key for the increased success observed, while undispersed seeds, falling under mother plants, suffered higher predation and lower seedling emergence and survival. The ability of this pioneer shrub to get established in open ground is crucial for vegetation colonization and restoration, especially on degraded lands affected by desertification, where they act as nurse plants for other species. Lizards are key in this process, which has important consequences for community structure and ecosystem functioning.

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Recent data demonstrate that flower-visiting and fruitconsuming lizards are strikingly more common on islands compared with the mainland, making them a true island phenomenon. We believe that different DC responses of insular animals might create this phenomenon. However, to confirm this we need more systematic data sampling from mainland and island. Some lizard -plant interactions might be excellent systems with which to study mutualism and potential coevolution between interacting plants and animals, (e.g. Phelsuma -flower mutualisms and Gallotia -fruit mutualisms). In particular, we need more experimental studies to demonstrate lizards that could cause evolutionary changes in flower and fruit traits in island plants. Many island lizard taxa are threatened by extinction or have already disappeared. The importance of mutualisms between plant-feeding lizards and flowering plants add very strong arguments to more joint conservation efforts for these groups of organisms.

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Ecological and evolutionary interactions between island plants and animals are taken in account. Species dispersing over long distances to remote oceanic islands leave their mainland food web behind. If colonizers are able to fit into the new insular food web in their receiver habitats they become established. This new insular webs include some interactions which are uncommon on the mainland: lizards and birds act as pollinators and seed dispersers more often than was believed until a few years ago. These animals become plant mutualists through a simple series of processess: Low species density on islands leads to relaxed interspecific competition, niche widening and high abundances of some species. The wider niche of predominantly arthropod-eating lizards and birds include nectar, pollen and fruit.

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Aim We discuss biogeographical hypotheses for the Mediterranean lizard species Podarcis and Teira within a phylogenetic framework based on partial mitochondrial DNA sequences. Methods We derived the most likely phylogenetic hypothesis from our data set (597 aligned positions from the 12S rDNA and phenyl tRNA) under parsimony, distance and maximum likelihood assumptions. Results The species usually included in Teira do not form a strongly monophyletic clade. In contrast, the monophyly of the genus Podarcis is rather well supported. Seven lineages are identified in the genus; in order of appearance within the tree, these are: the Balearic pityusensis and lilfordi pair, the sicula complex, a Tyrrhenian tiliguerta and raffonei pair, muralis, the Siculo-Maltese filfolensis and wagleriana pair, the Balkan group (erhardi, peloponnesiaca, milensis, melisellensis and taurica), and the Ibero-Maghrebian group (bocagei, atrata, hispanica and vaucheri). Conclusions The origin of the three European genera of lacertid assayed (Lacerta, Teira and Podarcis) is hypothesized to have occurred in the Oligocene. For Podarcis, a possible scenario of a Miocene diversification is derived from the sequence data, and the zoogeography of the lineages are discussed in relation to the palaeogeography of the Mediterranean. It is hypothesized that in the early history of the genus the main lineages separated by rapid, numerous and close events that produced a starting point very similar to a polytomy, hard to resolve by parsimony analysis of the data set.

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The thermal ecology of ectotherms has been studied for almost two centuries, but additional attention is currently being paid to the issue in order to understand how organisms deal with the environment in a climate change context. However, a consensus is still far away, due to the large number of factors involved and their complex interactions. In this context, three analyses in lacertid lizards were carried out: (1) a meta‐analysis, to test for differences between body and air temperatures from 71 populations, (2) a meta‐analysis concerning correlations between body and air temperatures from 60 populations, and (3) a multimodel inference using thermoregulation effectiveness indices from 45 populations. The importance of different factors, including body size, habitat, insuraliry, altitude, climate, and season, was evaluated in all analyses in order to model the response variables. A strong seasonality effect was observed, with a consistent pattern of less effective thermoregulation in summer compared to other seasons. Altitude was the second most important factor, with a consistent higher thermoregulation effort in populations occurring at high elevations (> 1000 m asl). Other factors, such as insularity or body size, can also be important, but did not exhibit a clear pattern. Finally, thermoregulation was less affected by climate and habitat type.

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Most lizards maintain quite constant body temperatures by behavioural means. Seasonal variations of environmental factors, such as temperature, sunlight exposure and wind intensity, influence lizard thermoregulatory abilities. Understanding how seasonal environmental shifts influence lizards’ thermoregulation helps us to know how they deal behaviourally with environmental changes, in general. We examined seasonal shifts (spring vs. summer) in behavioural thermoregulation in Podarcis lilfordi from Binicodrell islet (Menorca, Spain). Operative temperatures varied between microhabitats and seasons, being lower in spring than in summer, regardless of sunlight exposure. Lizard body temperatures were also lower in spring than in summer. Lizards used sunny microhabitats more frequently in spring and shaded areas in summer. Habitat thermal quality was similar during both seasons, but lizards thermoregulated less accurately in spring than in summer. Thermoregulatory effectiveness was low in spring (0.28) and moderate in summer (0.76). In comparison with previously published results, our findings showed the marked seasonal variation in the effectiveness of thermoregulation amongst island populations, which should be considered in future comparative studies.

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Antipredatory defenses are maintained when benefit exceeds cost. A weak predation pressure may lead insular lizards to tameness. Podarcis lilfordi exhibits a high degree of insular tameness, which may explain its extinction from the main island of Menorca when humans introduced predators. There are three species of lizards in Menorca: the native P. lilfordi, only in the surrounding islets, and two introduced lizards in the main island, Scelarcis perspicillata and Podarcis siculus. Besides, there are three species of snakes, all introduced: one non-sauriophagous (Natrix maura), one potentially non-sauriophagous (Rhinechis scalaris) and one sauriophagous (Macroprotodon mauritanicus). We studied the reaction to chemical cues of snakes of five populations: (1) P. lilfordi of Colom, (2) P. lilfordi of Aire, (3) P. lilfordi of Binicodrell, (4) S. perspicillata, and (5) P. siculus, ordered by increasing level of predation pressure. We aimed to assess the relationship between predation pressure and the degree of insular tameness regarding scent recognition. We hypothesized that P. lilfordi should show the highest degree of tameness, S. perspicillata should show intermediate responses, and P. siculus should show the highest wariness. Results are clear: neither P. lilfordi nor S. perspicillata recognize any of the snakes, while P. siculus recognizes the scent of M. mauritanicus, reacting with typical well-defined antipredatory behaviours. In general, our results suggest that chemical discrimination might be evolutionarily lost sooner than other antipredatory adaptations, such as tail autotomy or escape behaviour.

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Selection of thermally suitable microhabitats plays an important role in the thermoregulation of ectotherms. We studied microhabitat preferences in two populations of the Balearic lizard, Podarcis lilfordi, that live on two coastal islets of Menorca (Balearic Islands, Spain: Aire and Colom). To assess the roles of different microclimatic traits driving lizards’ decisions, we employed a case/control design. We measured microclimate variables in locations used by lizards (cases) and in paired random unused locations (controls). By comparing paired cases vs controls, we prevent spatial and temporal variation of environmental conditions. In order to test if microhabitat selection depends on thermoregulation requirements, we studied lizards in three situations: (1) ‘cold’, when body temperatures (Tb) of lizards were below their preferred temperature range (PTR), (2) ‘optimal’, when Tb were within the PTR, and (3) ‘warm’, when Tb exceeded the PTR. Substrate temperature was the main abiotic trait that determined microhabitat preferences of P. lilfordi, sometimes in conjunction with air temperature, while wind speed and humidity were not significant. ‘Cold’ lizards selected warmer microhabitats than the mean, but only on Colom islet. Notably, ‘optimal’ lizards also preferred microhabitats that were warmer than their surroundings, and ‘warm’ lizards did not select cold microhabitats in order to cool themselves, but rather acted randomly regarding temperature, wind and humidity. These results for ‘optimal’ and ‘warm’ lizards were consistent for both islets. We also studied the beginning and end of lizards’ diel activity. We found that lizards on Aire were active for approximately one hour more per day than lizards on Colom, which might be related to differences in melanism. However, activity started at an air temperature of approximately 17–19°C and finished at approximately the same temperature on both islets.

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During spring and summer, we studied the thermal ecology of two populations of the Balearic lizard, Podarcis lilfordi, from two coastal islets of Menorca (Balearic Islands, Spain): Aire and Colom. We calculated the accuracy of thermoregulation, that is, thFe extent to which body temperatures are close to species` thermal optima, the thermal quality of the habitat as the proximity of operative temperatures to thermal optima and effectiveness of thermoregulation, as the extent to which accuracy is higher than thermal quality of the habitat. We found that seasonality affects thermoregulation differently, depending on the lizard population. Those effects are consistent for all thermal parameters under study. The effects of seasonality were significantly stronger in Aire than in Colom islet. Many factors may be responsible for this different effect of seasonality, from differences on physiological traits to differences in the environmental conditions of the two islets, as their resource availability, predator pressure or habitat structure. Identifying the factors that boost or inhibit those seasonal changes would be important to understand thermoregulation in lizards. Slight changes on two similar populations can lead to great differences in thermal ecology of conspecific ectotherms.

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Islands provide a great system to explore the processes that maintain genetic diversity and promote local adaptation. We explored the genomic diversity of the Balearic lizard Podarcis lilfordi, an endemic species characterized by numerous small insular popula- tions with large phenotypic diversity. Using the newly available genome for this species, we characterized more than 300,000 SNPs, merging genotyping-by-sequencing (GBS) data with previously published restriction site-associated DNA sequencing (RAD-Seq) data, providing a dataset of 16 island populations (191 individuals) across the range of species distribution (Menorca, Mallorca, and Cabrera). Results indicate that each islet hosts a well-differentiated population (FST = 0.247 ± 0.09), with no recent immigration/ translocation events. Contrary to expectations, most populations harbor a considerable genetic diversity (mean nucleotide diversity, Pi = 0.144 ± 0.021), characterized by overall low inbreeding values (FIS < 0.1). While the genetic diversity significantly decreased with decreasing islet surface, maintenance of substantial genetic diversity even in tiny islets suggests variable selection or other mechanisms that buffer genetic drift. Maximum- likelihood tree based on concatenated SNP data confirmed the existence of the two major independent lineages of Menorca and Mallorca/Cabrera. Multiple lines of evi- dence, including admixture and root testing, robustly placed the origin of the species in the Mallorca Island, rather than in Menorca. Outlier analysis mainly retrieved a strong signature of genome differentiation between the two major archipelagos, especially in the sexual chromosome Z. A set of proteins were target of multiple outliers and primar- ily associated with binding and catalytic activity, providing interesting candidates for future selection studies. This study provides the framework to explore crucial aspects of the genetic basis of phenotypic divergence and insular adaptation.

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Reptiles Sobre este grupo existe una enorme diferencia en el grado de conocimiento entre las especies. Mientras que existe mucha información sobre los lacértidos, principalmente sobre la lagartija balear (Podarcis lilfordi), centrándose en distribución, situación actual, reproducción, ecología trófica, genética, ..... e incluso se ha descubierto recientemente una nueva población de una subespecie ya conocida (Illot d`en Mel), Podarcis lilfordi balearica, hay otros grupos sobre los que se tiene un escaso conocimiento.

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Caudal autotomy is an effective antipredator strategy widespread among lizards. The shed tail thrashes vigorously for long periods to distract the predator and facilitate the lizard`s escape. This movement is maintained by energy supplied by the anaerobic conversion of glycogen into lactate. It has been suggested that lactate accumulation serves as an index for the vigor of tail thrashing. We made three predictions: (1) tail loss frequency should be higher under heavier predation regime, (2) the duration of postautotomy tail movement should be extended in populations under heavy predation pressure as an adaptation to the higher risk and the increased need for defense, and (3) as result, lactate in these tail tissues should be concentrated at higher levels. To eliminate the impact of phylogeny and environmental factors on the interpretation of our result, we focused exclusively on one species, the Balearic lizard (Podarcis lilfordi). We studied three populations, Colom (Illa d`en Colom), Aire (Illa de l`Aire), and Sargantana (Illa Sargantana), under different predation pressure but sharing the same climatic conditions. We found no differences among the studied populations either in postautotomy duration of tail movement or in levels of final lactate accumulation while autotomy frequency was higher where predation pressure was more intense. Tail loss effectiveness is directly influenced by the level of predation, while secondary features of the trait appear to remain independent from the impact of environment.

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Aim We describe current interisland similarities of endemic faunas, and elucidate the significance of historical factors and environmental ones in determining the pattern found. Location The six major islands of the Balearics (Western Mediterranean). Method An extensive review of all the endemic fauna ranging from platyhelminthes to mammals is made. From 568 presumed endemic species and subspecies, 230 full species with neither taxonomic nor distributional uncertainty are chosen. Inter-island similarities are determined using such a presence-absence matrix. Finally, relationships between the matrix of faunistic similarity and a number of matrices measuring environmental and historical factors are elucidated. Results Endemic fauna similarities depend clearly on historical factors. Dependence on environmental factors is unclear. Moreover, endemic fauna reveals two clear-cut clusters of islands within the Balearics: the Gymnesic Islands, in the NE, and the Pityusic Islands in the SW. Historical factors cluster the Balearic Islands in the same way. Contrasting, environmental variables show smoothed, no significant differences among the Gymnesics and the Pityusics. Main conclusions Pre-human flora (palynology) and fauna (bird and mammal fossil record) suggest that environmental differences among the Gymnesics and the Pityusics have now been reduced in comparison to the environmental differences at the Pleistocene and Holocene boundary. This environmental homogenization is likely related with human invasion. Historical effects of prehuman differences between Gymnesic and Pityusic Islands are still recognizable on endemic fauna. In contrast, there is no historical effects on interisland similarities using currently breeding birds (as an example of organisms well-dispersed and related to vegetation type). We explain the pattern of interisland similarities of endemic fauna as the result of the independent histories among the two islands groups. Contrasting, successive colonizations and extinctions would determine interisland similarities of breeding birds.

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The development of molecular methods is becoming a promising field in the analysis of parasite fauna in wildlife species. This is especially useful in the case of parasite species where developmental larval stages are difficult to assess using standard methods. In this study we screened for the presence of parasitic nematodes infecting lacertid lizards from the Iberian Peninsula and Balearic islands using nematode-specific 18S ribosomal RNA gene primers on host tissue samples. Sequencing of positive samples revealed the presence of different genera of nematodes. The detection of Strongyloides, a monoxenous genus reported for the first time in Podarcis lilfordi is probably the result of the amplification of larval stages present in the host circulatory system. Two spirurid nematodes, Synhimantus and a new unidentified clade, were also found, suggesting that reptiles might be paratenic hosts of several spirurid species. This study demonstrates the benefits of using specific molecular markers on tissue samples to identify infecting larval stages of nematodes, otherwise difficult to assess using traditional screening methods.

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The ecological characteristics of three coastal islets of Menorca (Balearic Islands) were compared, as well as reproductive variables of their Balearic Lizard populations. Islets under analysis, Aire (Illa de l`Aire), Rey (Illa del Rei) and Colom (Illa d`en Colom), showed differences in trophic availability, human and predator presence, surface and geological age. Population density and female body size were different in the three populations. Howeevr, even under different selective pressures, populations didn`t show differences in clutch size, eggs size and mass, or reproductive effort. Wefound a lengthy reproductive period (May to July) and multiple cutches (2 annual clutches). Three islets had a mean clutch size of 2.12 ± 0.13 eggs (ranging between one and four eggs per clutch). We did not detect a relation between clutch size and female body size. We saw a elationship between length or mass, and the clutch size.

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Understanding the evolution of conspicuous colour patterns has been a major challenge in evolutionary biology since darwin’s formulation of naztural and sexual selection 150 years ago. A striking case of conspicuous colouration is the structural blue colour found in lizards belonging to several families, including lacertids (Lacertidae). Blue colouration can be restricted to discrete patches, as those found in the flanks or head of many lacertids, or can extend over large areas of the integument as in several insular populations of Lacertini. Recent research has shown that the blue flank and head patches of many lavcertids have their peak of reflectance in the ultravolet (UV) range. It has been suggestes that these UV-blue patches may be part of a private (i.e. available only to receptors with UV vision) communication system. In contrast, nothing is known about the spectral characteristics of those species in which all or large portions of the body surface are blue. Using objective methods of colour measurement and analysis, we studies the spectral characteristics of blue colouration in Podarcis lilfordi kuligae and compared them with those from other blue lacertids. The ventral surface and flank patches of P. lilfordi kuligae are both UV-blue, but their spectral shape is strikingly different, possibly reflecting different underlying selewctive pressures and colour production mechanisms. To our knowledge, this is the first recorded case of polychromatism in the UV part of the electromagnetic spectrum. Our results show that a wide range of spectrally different colouration belie human-perceived blues in lacertids. We analyse visual interactions among lacertid colours and habitat natural backgrounds and propose some hypothesis for the evolution of lizard blue and UV-blue colouration.

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Many animals display complex colour patterns that comprise several adjacent, often contrasting colour patches. Combining patches of complementary colours increases the overall conspicuousness of the complex pattern, enhancing signal detection. Therefore, selection for conspicuousness may act not only on the design of single colour patches, but also on their combination. Contrasting long- and short-wavelength colour patches are located on the ventral and lateral surfaces of many lacertid lizards. As the combination of long- and short-wavelength-based colours generates local chromatic contrast, we hypothesized that selection may favour the co-occurrence of lateral and ventral contrasting patches, resulting in complex colour patterns that maximize the overall conspicuousness of the signal. To test this hypothesis we performed a comparative phylogenetic study using a categorical colour classification based on spectral data and descriptive information on lacertid coloration collected from the literature. Our results demonstrate that conspicuous ventral (long wavelength-based) and lateral (short wavelength-based) colour patches co-occur throughout the lacertid phylogeny more often than expected by chance, especially in the subfamily Lacertini. These results suggest that selection promotes the evolution of the complex pattern rather than the acquisition of a single conspicuous colour patch, possibly due to the increased conspicuousness caused by the combination of colours with contrasting spectral properties.

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Through 17 years and from a sample of 7,790 faecal pellets and 26,346 prey items, we studied the diet of the Balearic lizard Podarcis lilfordi in Aire Island (Menorca, Balearic Islands, Spain). We analysed the diet in terms of prey frequencies, as well as by their volume and biomass contributions. The diet of the Balearic lizard was extremely variable through the years, months and areas under study. The dominance of small clumped prey, particularly ants, was confirmed. However, the main contribution by volume corresponded to beetles, with a relevant role for Diplopoda and terrestrial Isopoda during some months and at particular areas of the island. Several prey items were probably captured at the base of shrubs, under stones or inside rock crevices. Therefore, our estimations of electivity would only be reliable for epigeal and flying prey. The capacity of the Balearic lizard to include marine subsidies in its diet, such as coastal crustaceans, is noteworthy. Also, its consumption of carrion from carcasses of gulls and rabbits and leftovers from human visitors is remarkable. Juvenile conspecifics can also be a sporadic food resource, especially during the second half of summer, whereas the consumption of vegetal matter is constant for each whole year. The shifts of vegetal exploitation among areas of the island and months take place according to availability of different plant species at each area or during a given period. Thus, lizards are able to conduct a thorough monitoring of plant phenology, exploiting a large variety of plant species. Omnivory does not imply the indiscriminate inclusion of any edible food in its diet. Rather, the inclusion of several food items means the adoption of a wide range of foraging behaviours adapted to the exploitation of each food resource.

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A more generalized diet, as well as higher plant consumption by lizards in islands with poor trophic resources, has been widely documented. From some years ago, it has been ob- served individuals of the Balearic lizard, Podarcis lilfordi (Lacertidae), climbing to Carlina corym- bosa (Asteraceae) in Aire Island (Menorca, Balearic Islands, Spain) and foraging on their owers during the blooming period, from early July to late August. Through focal observations, we have studied the foraging behaviour of P. lilfordi on C. corymbosa. We obtained fourteen variables, from which we de ned three groups according to the information they provide: movements and foraging strategy, use of C. corymbosa as a trophic resource and foraging behaviour of P. lilfordi on that plant species. The analysis of these variables shows that P. lilfordi is a widely forager that employs a mixed strategy of licking and pulling up Carlina owers. This behaviour is probably due to a low production and/or a dif cult availability of nectar. Some behavioural traits are similar to those observed while foraging on carcasses. We also studied, during the same period, the diet of P. lilfordi through the analysis of faecal samples. We observed that the consumption of plant ele- ments is important during July and August, and that C. corymbosa is an important resource in the areas of the island where it is present.

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During the blooming period of the thistle Carlina corymbosa L. (Asteraceae) on Aire Island (Menorca, Balearic Islands, Spain), the Balearic lizard, Podarcis lilfordi, climbs the plant and forages on its inflorescences. We studied this foraging behaviour by means of observation. We collected data on fourteen variables belonging to three groups: movements and foraging strategy, use of C. corymbosa as a trophic resource, and foraging behaviour of P. lilfordi on this plant species. Analysis of these variables shows that P. lilfordi employs a mixed strategy of licking and plucking C. corymbosa flowers, probably due to a low nectar production and/or its difficulty of access. Interestingly, some behavioural traits are similar to those observed while foraging on carcasses. We also studied the diet of P. lilfordi through analysis of faecal samples. We found that C. corymbosa is a key food resource during summer. Foraging on C. corymbosa led to consumption not only of plant elements, but also of different proportions of flying and terrestrial prey by lizards living in areas of the island with or without C. corymbosa. In this manner, the consumption of a plant species during a short period of annual activity has an unexpected influence on the overall diet of these lizards.

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Even in solitary foragers, conspecifics can provide reliable information about food location. The insular lizard Podarcis lilfordi is a solitary species with high population densities that sometimes aggregate around rich food patches. Its diet includes novel and unpredictable resources, such as carcasses or plants, whose exploitation quickly became widespread among the population. We tested the use of social information by lizards through some field experiments in which they had to choose one of the two pieces of fruit. Probably due to local enhancement, lizards preferred to feed on the piece of fruit where conspecifics or lizard-shaped models were already present. Conspecifics’ behaviour, but also their mere presence, seems to be a valuable source of information to decide where to feed. Lizards also showed a strong attraction to conspecifics, even in the absence of food. Maybe the presence of a group is interpreted as an indirect cue for the presence of food. The group size was not important to females, but males had a significantly higher attraction towards groups with three conspecifics. We discuss some characteristics of P. lilfordi at Aire Island that can explain the development of the observed social foraging, as well as their possible consequences.

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Even in solitary foragers, conspecifics can provide reliable information about food location. The insular lizard Podarcis lilfordi is a solitary species with high population densities that sometimes aggregate around rich food patches. Its diet includes novel and unpredictable resources, such as carcasses or plants, whose exploitation quickly became widespread among the population. We tested the use of social information by lizards through some field experiments in which they had to choose one of the two pieces of fruit. Probably due to local enhancement, lizards preferred to feed on the piece of fruit where conspecifics or lizard-shaped models were already present. Conspecifics’ behaviour, but also their mere presence, seems to be a valuable source of information to decide where to feed. Lizards also showed a strong attraction to conspecifics, even in the absence of food. Maybe the presence of a group is interpreted as an indirect cue for the presence of food. The group size was not important to females, but males had a significantly higher attraction towards groups with three conspecifics. We discuss some characteristics of P. lilfordi at Aire Island that can explain the development of the observed social foraging, as well as their possible consequences.

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Foraging diurnal lizards are well known for their use of visual and chemical cues to detect prey. We already showed that the Balearic lizard is able to detect prey using visual and chemical cues, even from airborne odors. In this study we carried out a field experiment to test if lizards can detect prey using acoustic cues. Our results show that Podarcis lilfordi is able to detect flies trapped inside opaque cups, only using acoustic cues. To ourknowledge, this is the first known case of phonotaxis of a diurnal lizard. Thus, P. lilfordi can detect, from far away, current pollinators trapped inside floral chambers of the dead horse arum, Helicodiceros muscivorus. This is another behavioral trait displayed by the Balearic lizard during its complex interaction with the dead horse arum.

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Aims: To characterize the genetic and morphological diversification of the endan- gered Balearic lizard Podarcis lilfordi and to assess the relevance of this diversity, and how it is described, to conservation measures. Location: This study covers all the populations of the Balearic lizard, Podarcis lilfordi, present in its range of distribution at coastal islets of Menorca, Mallorca and Cabrera Archipelago. Methods: We analysed genetic and morphological variation across the 43 known extant populations of the Balearic lizard, using mitochondrial and nuclear markers. We examined morphometric and scalation characters using, in some cases, phyloge- netically independent contrasts. We also incorporated the study of dorsal coloration and dorsal colour pattern including the analysis of melanism in several populations. Results: We detected clear genetic divergence between Menorcan populations and populations from Mallorca and Cabrera, in both nuclear and mtDNA markers, but genetic divergence is relatively low among different insular populations within these groups. In contrast, morphological divergence was substantial both between Menorcan and remaining populations and within these groups. Morphological traits, such as dorsal coloration, body size and the number and size of scales, seemed to be linked with differences in climatic conditions between populations. In addition, some traits, as melanism, showed a strong phylogenetic signal. Main conclusions: The morphological and genetic diversity of the Balearic lizard is incongruent with the subspecies described in the classical taxonomic literature. Moreover, current populations differ not only in some genetic and morphological features, but also in several ecological and ethological characteristics, in many cases unique to one population. Based on our results, we propose abandoning the use of subspecies to describe the extraordinary morphological diversity of the Balearic liz- ard and its replacement with the concept of evolutionary significant units (ESUs). ESUs are particularly suitable to describe and recognize such diversity and, especially, to ensure the continuity of the evolutionary process.

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During the last 24 years, the mutualistic interaction between the dead horse arum, Helicodiceros muscivorus, and the Balearic lizard, Podarcis lilfordi, was studied on Aire Island (Balearic Islands, Spain). From a small population of a hundred plants, the dead horse arum expanded extraordinarily throughout the island, reaching the highest known densities of the species and occupying areas of the island where it was not previously present. The current abundance of plants is a direct effect of the frugivorous activity of the Balearic lizard, which is the main, if not the only, effective seed disperser of the plant on Aire Island. However, abiotic factors predominated over biotic factors in driving abundance of plants. Over the years, plant densities varied significantly depending on the aridity of the island, with higher densities recorded in drier years. Lizards’ frugivorous activity and dispersal intensity was inversely correlated with annual rainfall. We found higher dispersal intensity in years with lower rainfall. We propose that the years of lower rainfall are those in which there is a lower prey availability. In such years, lizards compensate the shortage of other trophic resources with a more intense consumption of dead horse arum fruits. The mutualistic interaction is therefore asymmetric, since there is a greater influence of the frugivorous activity of the lizards on the plants than of the plants on lizards. It is, in short, a system chronically out of balance.

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Cost-benefit models of escape behaviour predict how close a prey allows a predator to approach [flight initiation distance (FID)] based on cost of not fleeing (predation risk) and cost of fleeing (loss of opportunities). Models for FID have been used with some success to predict distance fled (DF). We studied effects of foraging opportunity cost of fleeing and examined differences between age-sex groups in the omnivorous Balearic Lizard, Podarcis lilfordi. Balearic lizards forage on the ground for invertebrate prey and climb the thistle Carlina corymbosa to forage on its inflorescences. We studied escape behaviour in three experimental groups, with human beings as simulated predators: lizard foraging above ground on C. corymbosa, foraging on the ground away from thistles and on the ground with cut inflorescences. Flight initiation distance was shorter for lizards with cut inflorescences than for (1) lizards above ground due to the greater risk above ground due to conspicuousness of black lizards on yellow flowers; and (2) lizards on ground away from flowers due to the cost of leaving while feeding. The only age-sex difference was slightly greater FID for adult males than subadults, presumably because larger adult males are more likely to be attacked by predators. Other potential factors affecting this difference are discussed. Experimental group and age-sex group did not interact for FID or DF. Because lizards foraging on inflorescences above ground fled to the base of the plants to refuge provided by spiny thistle leaves, their DF was shorter than in the other groups, which fled across the ground, usually without entering refuge. DF did not differ between groups on the ground or among age-sex groups. The predicted shorter DF for lizards with cut inflorescences than on ground without inflorescences did not occur. We hypothesize that the opportunity cost was small due to the abundance of blooming thistles and that DF may be less sensitive to opportunity cost than FID.

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From 1999 to 2005 we studied the population of the dead horse arum, Dracunculus muscivorus (Araceae) and its relationship with the Balearic lizard, Podarcis lilfordi (Lacertidae, Squamata).

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The Balearic lizard, Podarcis lilfordi, is one of the key species of Menorca Biosphere Reserve. This is the only endemic terrestrial vertebrate Plio-Pleistocene, the last representative of vertebrate fauna previous to the arrival of humans. Over the past two decades since the establishment of the Biosphere Reserve, have accumulated a significant amount of knowledge on this species, both on its molecular evolution, as their demographics, characteristics of natural history, ecology, behavior and state conservation of populations Menorcan. However, some fundamental aspects of the situation of current populations are unknown and others provide amazing results from the point of view of Conservation Biology. While some traditional threats affecting the Balearic lizard seem to have disappeared or have been attenuated, new ones have emerged in recent years and old problems, which appeared to be over, have resurfaced. Human pressure on fragile populations of the Balearic lizard is manifested in many different ways and forms, as now, the main factor of uncertainty about the future of this unique species. In this paper, we review summarizes the current state of knowledge on this endemic Lacertidae, try to identify the main factors still act as threats surviving populations in coastal islets and propose some actions that would ensure the future maintenance of P. lilfordi within the Biosphere Reserve.

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Here we show the role of the Balearic lizard Podarcis lilfordi fenni in the pollination of the sea fern Crithmum maritinum on the islet of Nitge.

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New information on the geographical location of the population of the Balearic lizard described as Podarcis lilfordi carbonerae Pérez-Mellado & Salvador, 1988 is given. The records of the herpetological collection of the Alexander Koenig Museum of Bonn, the capture dates of specimens and three recent surveys to coastal islets of Menorca (Balearic Islands) showed that the capture locality so-called Isla Carbonera (Na Corberana) corresponds to En Carbó islet (Illot d`en Carbó), off northern Minorcan coast. New colour, design and morphometric data of lizards from En Carbó confirm the validity of the subspecies P. lilfordi carbonerae. The present day situation and conservation status of the lizard population from En Carbó are discussed.

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We examined the diets of several species of Podarcis from different western Mediterranean islands. We tested the prediction of more generalized diets in lizards from poor environments. We also examined the extert and mode of herbivory in relation to arthropod diversity in the diet. Lizards from the Tuscan Archipelago, P. sicula from Menorca, and P. tiliguerta from Corsica all show a rather generalized diet. In contrast, P. lilfordi and P. pilyusensis from the Balearic Islands and, to a lesser extent, P. hispanica from Benidorm Island, appear much more stenophagous, including a high proportion of clumped prey in their diets. Plant matter is a common food item in most of the population studied, specially in Balearic lizards. A marked seasonal shift in the degree of herbivory was observed in these species where high-energy plant parts are frequently consumed during summer. In one of the Balearic Islands (Nitge), the bulk of the summer diet was formed by pollen and nectar of one particular plant species. Herbivory, consumption of clumped prey and other dietary peculiarities of insular populations of Mediterranean lizards indicate a very flexible feeding behaviour compared to mainland congenerics. This could result from a lack of predation pressure allowing high population densities to be reached in islets with poor trophic resources. Differences found in dietary characteristics among island populations can be interpreted as a consequence of different current ecological conditions, as well as historical and biogeographical differences among the islands.

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Tail autotomy is one of the main anti-predator mechanisms of lacertid lizards, but it has been predicted that it is only retained in its full capacity when its benefits exceed its costs (Arnold, 1988). To test this hypothesis, ease of tail shedding was examined in a number of continental and insular lacertid lizard populations, each of which showed a different shedding capacity. Tails are shed more easily in those continental and insular populations where there is a greater probability of predation. In insular populations not subjected to strong predation, the tail tends to be retained. The relationship of these findings to insular Mediterranean lizard populations and to the extinction of the Balearic lizard, Podarcis lilfordi are discussed.

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Knowledge of Balearic amphibians and reptiles is closely linked to the development of European herpetology itself. The first herpetological study of the Balearic Islands was made at the end of the 18th century and during the first decades of the 19th century. We divide herpetological explorations of the Balearic Islands into three periods: first, a general approach by local naturalists and travellers; second, scientific exploration of the archipelago by professional collectors and herpetologists from the most important European museums and universities, with studies mainly focused on systematics and taxonomy; and third, scientific description of evolutionary processes observed on islands and their relationship to emergent disciplines such as island biogeography and insular ecology. In this work, we review these most important steps in the development of herpetological knowledge of the Balearic Islands from two different and complementary approaches: the origin, personality and objectives of researchers, and the discoveries they made during more than two centuries.

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Blood parasites can have negative effects on lizard hosts, such as testicular reduction, low levels of haemoglobine, an increase of immature erythrocytes, low levels of oxygen consumption and a significant reduction of sprint speed. Thus, blood parasites are able to produce a measurable decrease in individual fitness. Factors as host density, abundance of invertebrate vectors and the sex or body condition of hosts can affect parasitic prevalence and intensity of infestation. In this piece of work we explore the extent of prevalence and intensity of haemogregarines intraerythrocytic parasites in several populations of the Balearic lizard, Podarcis lilfordi. 491 lizards from 37 different populations were studied. In average, less than 1% of erythrocytes were infected by haemogregarines, showing significant differences on the intensity of infection amongst populations under study. More than 90% of individual lizards were infected. These also showed significant differences amongst populations. In Menorca and Cabrera coastal islets, we found a significantly higher proportion of infected males than females. In Mallorca islets, bigger adult males were more prone to load blood parasites, while this effect was not detected in females. In the three groups of studied populations, Menorca, Mallorca and Cabrera, we found a significantly higher body condition of adult males than females. But body condition had no detectable effect in the intensity and prevalence of blood parasites. The prevalence, unlike the intensity, was significantly associated with lizard density. We compare our results with those of studies made with

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The use of space of the balearic lizard, Podarcis lilfordi. Causal factors at Aire Island. -- during April, June and July 2004 the use of space on a study plot of 2500 m2 at the central area of Aire Island (Menorca, balearic Islands, Spain) have been studied. This area is characterized by a dense shrub cover, mainly composed by Suaeda vera, as well as large areas of rocks and a very high density of the dead horse arum, Dracunculus muscivorus. 3324 captures and recaptures from 766 lizards were obtained. The average home range size was around 138 m2 for those lizards with four or more recaptures. We did not detect significant differences in home range size between adult males and females, nor among the three months under study. The home range size of the balearic lizard is similar to those recorded for other small lacertid lizards of the Mediterranean basin. We did not find any significant correlation between body size and home range size, with only marginally significant results for adult females. Anyway, in all partial analyses on each studied month the correlation was negative, perhaps indicating the occupation of smaller but better, from the viewpoint of available resources, home ranges by larger lizards. The extent of home range overlap is a clear indication of the absence of territorial behaviour in the balearic lizard, both in males and females. While during April, we observed lower home range overlap between adult females. on the other hand, adult males showed a higher home range overlap from June, in spite of a lower number of males present at the study plot during this month. This result could indicate a higher tolerance between males after disappearance of flowering dead horse arums. the monopolizing of open inflorescences during April did not lead in a different spatial distribution of males and females in relation to plants and both sexes exhibited similar distances to dead horse arums. however, during June, within the peak of the ripening period, distances to plants were significantly shorter in adult males. We discuss the significance of a not lasting resource as the dead horse arum for space use of the balearic lizard, contrasting with patterns observed at continental populations of small lacertid lizards, where refuges and other structural elements of the habitat are more relevant to explain the spatial distribution of lizards. We propose the hypothesis that these differences are only possible because of particular conditions of microinsular environments of the Mediterranean, characterized by poor trophic resources and a low predation pressure.

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Temporal changes in adult sex ratio of animal populations might be due to differences in movements, survival or detection probabilities. We used data from an intensive capture–mark–recapture study of 720 lizards at the islet of Aire (Balearic Islands, Spain) to investigate the demographic mechanisms underlying the spring uneven sex ratio. We simultaneously estimated survival (f), the proportion of transient animals (p) and the probability of recapture (p) of lizards at the study plot. We then estimated population size using open population models for individually based data and compared these with the observed values. Results indicated that males had a higher probability of recapture than females, but this was not sufficient to generate the observed male-biased sex ratio. The proportion of transient males decreased at the end of spring in parallel with the end of the blooming period of the dead horse arum, Helicodiceros muscivorus, a short-lasting food and thermoregulation resource for lizards during spring. Changes in the proportion of transients suggested that sex-dependent movements, most likely linked to a monopolising behaviour of this plant resource, were responsible for the observed difference in the number of males and females. Our results reveal how the interplay of behavioural and ecological factors explains short-term changes in population dynamics and shapes the movement patterns within the island.

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Lizards and gulls cohabit in several Mediterranean islands. The yellow-legged gull, Larus michahellis, was found to prey several vertebrate species. However, precise information about the interaction between gulls and other vertebrates, particularly with lizards is still scarce. The Balearic lizard, Podarcis lilfordi, shares several coastal islets with the yellow-legged gull. Using two different sources of information, we studied the interaction of both species in Colom Island (Menorca, Balearic Islands, Spain). We studied the diet of the yellow-legged gull and learnt that the Balearic lizard is not a common prey of the yellow-legged gull. On the other hand, we studied the potential predation pressure of gulls on lizards, using plasticine models of lizards. We did two different experiments from which we can conclude that yellow-legged gulls rarely attack lizards and, consequently, cannot be considered a major threat for this endemic lizard species, at least in the population under study. Finally, we obtained evidence that plasticine models can only be employed with caution to assess predation pressure of opportunistic scavengers, much as gulls are. The majority of marks on models were not the consequence of true attacks by gulls, but the result of ground exploratory behaviour of gulls in search of any edible matter. Therefore, contrary to popular belief, in the case of the yellow-legged gull, the proportion of marked models would be an indication of ground-based wandering activity, rather than a result of its predation pressure on lizards.

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he Balearic lizard, Podarcis lilfordi, is present in 43 insular populations in the Cabrera archipelago and around the coasts of Mallorca and Menorca islands (Spain). We studied lizard densities over the entire range of distribution, analyzing observed differences of density in relation to island area, habitat diversity, availability of resources, presence of predators, competitors and human disturbances. The density of the Balearic lizard varies from less than 35 to almost 8000 lizards ha-1, with an average of around 1500 lizards ha-1. In some very small islets we detected no more than 10 individuals. Using a subsample of nine coastal islets (Menorca) we did not find any significant correlation between ground arthropod biomass and lizard density. The combination of island area and its maximal altitude, its so-called biotic capacity, was also uncorrelated with lizard density. In addition, neither degree of island accessibility nor presence/absence of seagull breeding colonies, were able to explain lizard densities. Islands without ship rats (Rattus rattus) showed a significantly higher lizard density, but islands in which rat eradication programs were launched during the study period, showed lower densities than those with rats but no eradication actions. Genetic variability was significantly higher on bigger lizard populations, lacking a correlation with lizard densities. No single independent variable can explain density differences among populations under study. Our results are discussed in the light of available hypotheses on factors affecting population densities.

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An analysis of pollen grains loaded and transported by the Balearic lizard, Podarcis lilfordi, at three coastal islets of Menorca (Balearic Islands, Spain) was performed. We studied 228 individual lizards from spring and summer, 1998, recording 323,986 pollen grains belonging to 35 different plant species. As a consequence of its foraging behavior, the Balearic lizard is able to load large quantities of pollen. In Aire Island pollen load was higher in adult females than males. P. lilfordi is an important pollen loader of some plant species such as Pistacia lentiscus, Crithmum maritimum, Allium ampeloprasum, Carlina corymbosa, and Pancratium maritimum. The role of P. lilfordi as the main pollinator has been previously demonstrated only for the sea fern, C. maritimum. However, results reported here indicate that the Balearic lizard can play an important role in the reproductive success of other plant species on coastal islets off the main island of Menorca.

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Coastal islets of Balearic Islands share several ecological conditions, such as the scarcity of food resources and the lack of a strong predation pressure. During spring and summer 2006, we studied the thermal ecology of two populations of the Balearic lizard, Podarcis lilfordi, from two different coastal islets of Menorca (Balearic Islands, Spain): Aire and Colom. In both islets and seasons, we found that P. lilfordi regulates its body temperature rather accurately, showing effectiveness values ranging between 0,8 and 1. During spring at Aire islet, the vast majority of operative temperatures (Te) were out of the optimum range (Tsel). But, nevertheless, the Balearic lizard performed an effective thermoregulation. Lizards remained active in both islets for as long as they were able to, and were only inactive in the late afternoon of summer days. We found significant differences in Te from different habitats, showing a high heterogeneity of the thermal conditions in both islets under study. This habitat heterogeneity allows an effective shuttling heliothermic behavior of lizards. Differences found between islets are notable. There is a dramatic increase of thermoregulation accuracy between seasons in Aire, markedly less pronounced in Colom. Based on our study, we foreview that wind would produce a cooling effect, that would be stronger in Aire than Colom. Hence, in Aire islet, there was a more effective thermoregulation in summer than spring. Further research needs doing in order to check the potential role of melanism and other factors in such thermoregulation differences amongst populations of the same species.

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En este trabajo presentamos el estado actual de las poblaciones de Lagartija balear, Podarcis lilfordi , en la illa den Colom. Se describen algunos rasgos de su morfolog a, se al ndose la existencia de un neto dimorfismo sexual, con machos de mayor tama o corporal que las hembras. La densidad de poblaci n es variable en distintas zonas de la isla, con densidades bajas o medias en la zona central y m s altas en las zonas costeras. El ciclo reproductor comienza hacia el mes de febrero, observ ndose una conducta de vigilancia de pareja. El tama o de puesta es notablemente reducido, con una media de dos huevos por puesta. Sin embargo, se ha observado la existencia de m s de una puesta anual. La dieta es mixta, con la inclusi n de presas animales de peque o tama o y de numerosas especies vegetales. Se discute el papel de P. lilford i como dispersor de las semillas de algunas plantas, como el endemismo menorquin Daphne rodriguezii. Las Lagartijas baleares de la illa den Colom tienen un estado de conservacion adecuado. Se discuten algunas amenazas potenciales derivadas de los usos actuales de la isla.

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While the use of faecal pellets is widely accepted as a primary methodological source of data for dietary studies, a recent paper advocated for the use of gut contents. This was due to the fact that faecal samples would give biased results of the diet of arthropod predators, due to a lower representation of soft-bodied prey in faecal pellets. To test this assumption, we compared the spring diet of several populations of two insular lizards from the Balearic Islands (Spain), Podarcis lilfordi and Podarcis pityusensis, using both faecal pellets and gut contents. Our results do not support the supposed bias of dietary analyses based on faecal pellets. Indeed, soft-bodied prey and particularly insect larvae are often equally represented in faecal pellets and gut contents. Alternatively, soft bodied prey are represented in different proportions in gut contents and faecal pellets, but in some cases with higher proportions being observed in the gut contents, and in other cases with higher proportions in faecal samples. We conclude that faecal pellets can be a reliable source of information for dietary studies.

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The ecological conditions of Mediterranean islands favour the consumption of vascular plants by lizards and, consequently, the raise of several interactions, including plant pollination and seed dispersal. However, some interactions can be more complicated, with variable benefits or detrimental effects for lizards and plants. In this talk we describe the striking case of the Dead Horse Arum and the Balearic Lizard in Aire (Illa de l`Aire), a coastal islet of Menorca.

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In this work we describe the interaction of the dead horse arum and the Balearic lizard in Aire (Balearic Islands, Spain). In Aire Island (Illa de l`Aire), the dead horse arum, Dracunculus muscivorus, is particularly abundant. From 1999 to 2005 we studied the population of this plant species and its relationship with the Balearic lizard, Podarcis lilfordi. During blooming period, several lizards exhibited an intense foraging behaviour focused on open inflorescences. Lizards were able to capture flies attracted by the plants and those trapped in tubules as pollinators. The exploitation of pollinators was principally made by largest males of the population that actively excluded females and smaller males from plants, skewing lizard sex-ratio in areas of maximum plant density. Lizards consumed fruits following the progressive fruit maturation. In two germination experiments, we detected an enhanced germination of seeds from lizards’ faeces, in comparison with those directly taken from ripening fruits. Thus, the Balearic lizard is the main legitimate disperser of the dead horse arum. From 1999 to 2005, the density of the dead horse arum increased from 4800 ind./ha to more than 25.000 ind./ha in some optimal areas of the islet, indicating a very positive balance of the interaction between plants and lizards.

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In this study we examine the consumption and seed dispersal of the vascular plant, Phillyrea media by this lizard in the coastal islet of Rey , Port of Mahón (Menorca, Balearic Islands) and the consequences of this foraging behaviour in the natural regeneration of native vegetation of this islet.

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A studie was carried out on 17 populations of Podarcis lilfordi inhabiting the islets off the coast of Menorca (Balearic Islands). Pattern and colouring together with the statistical analysis performed suggested that the menorcan rassenkreis comprises a total of 9 subspecies. The evolutionary processes involved appear to be fundamentally governed by the age of the islets, their distance from the coast and by their ecological conditions. Though in certain cases it may be postulated that genetic drift may have acted as a differentiating mechanism in populations which were initially small. However, interpretation of the microevolutionary processin Menorca is more difficult thnin the case of other rassenkreis of the Balearic Islands due to extinction of the `mother` population on the main island.

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Different kinds of interactions between lizards and plants in the Mediterranean basin have been described. Lizards have shown to `use` plants as a refuge against predators, as a foraging site, as a thermal microhabitat or as a food resource. In the last case, they can either act as herbivores (+/- interaction, consuming vegetative and/or reproductive parts, and damaging the plant to a higher or lower degree) or as mutualists (+/+ interaction, by behaving as legitimate pollinators and/or seed dispersers). The importance of plants as a food resource for Mediterranean lizards has been found to be high in insular habitats, espescially in small islands, where the paucity of arthropod prey availability redirects the foraging activity of lizards towards other nutrient resources. In such small islands, plants may play a major role in the trophic ecology of lacertid lizards, as suggested by recent studies. Likewise, lizards may be important both as efficient pollen transporters and seed dispersersfor a variety of plants. Some of these lizard-plant interactions are unique. The effect lizards have on the reproductive and dispersal succes of some species may be very relevant for plant preserveation, and in turn, the preserveation of prticular behavioral and ecological traits of the particular lizard populations depends, at least partly, on the plants they interact with.

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In this work the status of the Balearic lizard, Podarcis lilfordi, from Colom island (Illa d`en Colom) is presented. We describe some morphological traits, as the sexual dimorphism with larger males. Population density is quite variable between different areas of the island. We found lower densities at core areas and higher densities at coastal zones, close to sand beaches. The repoductive cycle starts very early, at least during the month of february. Clutch size is reduced to two eggs per clutch. However, in several females we found more than one clutch per year. The diet is a mixture of clumped prey types of small size and several plant species. The role of P. lilfordi as legittimate seed disperser of some plant species, as the Menorcan endemism Daphne rodriguezii, is discussed. At present, the Balearic lizards of Colom island have an adequate conservation state. The existence of some potential threats, derived from the present day use of the islands is also discussed.

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Background: In lacertid lizards from Mediterranean islands, frugivory is common, particularly under prey scarcity, a characteristic of small islands. In several populations, the diet of the Balearic lizard, Podarcis lilfordi, is extremely variable and includes fleshy fruits. However, frugivory is sporadic and there are very few examples of dominant fruit consumption. Results: We describe the existence of an extraordinary fruit consumption of a single plant species, the juniper, Juniperus phoenicea, by the Balearic lizard, P. lilfordi. In addition, for the first time in Lacertidae, we describe the exist‐ ence of scat piling in the population of these lizards inhabiting Cabrera Island (Balearic Islands, Spain). Scat piling was detected in an isolated location with hundreds of scats deposited by several individuals at a particular place. Conclusions: The high population density of lizards at the island of Cabrera and the great versatility of foraging behavior of this species allows us to hypothesize that scat piles could act as an attractor for numerous individuals, that is, as inadvertent social information. If that hypothesis is correct, it would result in the concentration of several indi‐ viduals foraging on a single or a few ripening plants. We cannot, however, rule out that individuals concentrated due to the scarcity of ripening plants in other areas, without any influence of the presence of several lizards, as attractors to the site. Our findings modify previous descriptions of the diet of the Balearic lizard in Cabrera made with smaller samples. In some places and periods of the year, frugivory on a single plant species can be extremely intense and only large sample sizes of scats allow to find these particular trends in the foraging ecology of insular lizards.

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Deceptive flowers from several plant species emit odors that mimic oviposition cues and attract female insects seeking for a laying site. Helicodiceros muscivorus is a species that emits an odor mimicking the foul smell of rotting meat and thereby attracts blowflies that usually oviposit on carcasses but are deceived into pollinating the plant. Thus, H. muscivorus is a striking case of pollination by brood‐site deception. The Balearic lizard, Podarcis lilfordi, exhibits remarkable interactions with dead horse arum. Balearic lizards, which sometimes forage on carcasses, are attracted to blooming dead horse arum. We showed experimentally that P. lilfordi can detect chemical cues from carcasses on cotton swabs and exhibits elevated tongue‐flick rates to carcass chemical cues compared to control stimuli. Lizards also detected and located hidden carcasses using only airborne chemical cues. The responses of lizards to chemical cues from the spadix of blooming dead horse arum were qualitatively and quantitatively similar to those to carcass odors. Therefore, the decay‐like odor that attracts blowflies for the plant`s benefit also attracts lizards. This attraction may initially have been somewhat favorable for lizards that eat blowflies, but slightly unfavorable for plants because the lizards ate some pollinators. We suggest that lizards attracted by odor may have learned later to use the plant for thermoregulation and then consume its fruits, making the association more positive for lizards and benefitted arum by seed dispersal.

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The horseshoe whip snake (Hemorrhois hippocrepis) is considered a species of recent introduction in the island of Mallorca (Balearic Islands), in contrast with Ibiza or Formentera where is catalogued as an invasive species. Since 2018, Servicio de Sanidad y Control de Fauna del Consorcio para la Recuperación de Fauna de las Islas Baleares in collaboration with Servicio de Protección de Especies of Conselleria de Medi Ambient i Territori, is carrying out the control of the horseshoe whip snake in Mallorca in areas of biological importance. These zones include areas of the Natura 2000 Network and/or areas where there is a presence of protected and/or endemic species. The aim of these campaigns is to control the density of the horseshoe whip snake to minimize its impact on wild species. During the 2022 campaign, a shed snakeskin was reported on the Illa dels Conills (the smallest islet of the Malgrats Islands), in the municipality of Calvià. After confirming this finding, we proceeded to prospect and place traps for the capture of snakes on the islet. The Illa dels Conils is located less than 200m from the coast, with an aera of about 10,000m2 and a maximum altitude of 30m. It is inhabited by endemic and catalogued species such as the Lilford’s wall lizard (Podarcis lilfordi) and the European storm petrel (Hydrobates pelagicus). Between May and November, a total of 10 traps were placed on the ground, with a the result of 1330 days of trapping and the capture of 6 horseshoe whip snakes. In addition, during this campaign two important findings were confirmed: (1) the absence of observations of the Lilford’s wall lizard on the islet, and (2) the predation of the horseshoe whip snake on the European storm petrel. Island ecosystems are one of the most fragile and threatened territories, usually hosting a greater biodiversity, as well as a greater number of endemic species. Therefore, they require special protection. Currently in Mallorca the number of introduced and invasive species is a growing concern, and highlights the need of implementing prevention measures and the necessary resources to be able to manage them properly.

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In order to establish the basic management guidelines for the most threatened amphibian and reptile species in the Balearic Islands, the Plan for the recovery and conservation of amphibians and reptiles in the Balearic Islands, known as Plan Boscà, has been developed and is pending its final approval. It is a group plan that includes two species of amphibians and three reptiles including: i) the populations of the Balearic toad Bufotes balearicus in Ibiza and the populations of the Ferreret Alytes muletensis in Mallorca, ii) the populations of the Moorish tortoise Testudo graeca on the island of Majorca, iii) the populations of the Balearic lizard Podarcis lilfordi from Majorca and Menorca and iv) the populations of the Pitiusan lizard Podarcis pityusensis from Ibiza and Formentera. In the plan they develop a set of management actions, which are divided between generic actions for the entire group of species contained in the plan and those specific to each species. The generic actions common to all species include: i) promoting research and training to improve knowledge, ii) dissemination and citizen participation, and iii) administrative coordination. The actions for the Balearic toad include i) knowledge of the current status of the species, ii) habitat management, with the review and updating of potential localities and the creation of new ones to favor connectivity and iii) monitoring of the species . The actions for the black tortoise include i) improving knowledge of the current distribution, ii) monitoring populations and creating and strengthening them, iii) improving connectivity between populations and iv) captive breeding. . The actions for the Balearic and Pitiusan lizard include i) updating knowledge and in-depth evaluation of its conservation status, ii) monitoring populations, iii) managing introduced species such as invasive snakes, iv) quality control of the habitat and v) the revision of the protection category in the Balearic Catalog of Threatened Species, as well as the revision in the official forms of the spaces integrated in the Natura 2000 Network.

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Here, we update the current list of amphibian and reptile fauna present in the Balearic Islands, probably the most outstanding case in the Mediterranean and of the most in the world where massive species introduction is in conflict with the survivorship of highly restricted endemic taxa. Resulting of a long term evolution in insularity, endemic herpetofauna was already decimated during the Pleistocene but, after the human colonisation of the archipelago, the introduction of alien species, passive or deliberate, has been provoking new extinctions and range retractions in the native herpetofauna. Such process is not interrupted but has even intensified during the last years. The current species list is composed by five amphibians (one native) and 21 reptiles (2 native). A critical review of the evidence on extinctions and introductions is provided together with the conservation implications. Compared to the last review (Mayol, 1985) six new reptile species are now naturalised or are in process of naturalization, colubrid snakes constituting the most conflicting element due to their predator role.

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We have assessed the isotopic signatures of C, N and S from sprouts, flowers and fruits of the dominant plants of the Mel islet, of their most abundant arthropods and of the endemic lizard Podarcis lilfordi, to produce a diagram of proximities between taxa allowing some inferences on the trophic dependence of this latter species. Despite the difficulties arisen from the spatial heterogeneity of the isotopic basal values, the close proximity of the lizard to certain arthropods suggests a selective animal diet and, in general, a reduced degree of omnivory, and do not support any suspicion of a lowered trophic level from insectivorous to vegetarian style due to restrictions of island life.

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A 684 bp fragment from cytochrome-b allowed a coherent arrangement of several Podarcis populations from the Balearic archipelago, in a study focused on the phylogeography of the 15 Minorcan populations of Podarcis lilfordi. A reference site with Podarcis lilfordi from Mallorca clusters with the Minorcan population, although it shares a few variations with Podarcis pityusensis that are not present in the Minorcan clade. Concerning the Minorcan islets, a two steps model is drawn accounting for the observed molecular pattern. An ancient and a derived stock of populations can be discerned, seperated by a population event replacing the former populations by the modernones on the shallowest protoislets, placing it around 7000 to 5000 BP, based on bathymetric information and Holocene sea level data. Autapomorphies are present in several sites and could be indicative of seperated demes prevailing on penninsular areas of the island, as in Cavalleria, Mola de Fornells, or even on larger regions as in the southeast Menorca. Within the framework of a vicariant model, we suggest that islet`s inhabitantshave thus retained some of the history of the now extinct mainland population.

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The monophyletic species subgroup of Podarcis tauricus is distributed in the western and southern parts of the Balkans, and includes four species with unresolved and unstudied inter- and intra-specific phylogenetic relationships. Using sequence data from two mitochondrial and three nuclear genes and applying several phylogenetic methods and species delimitation approaches to an extensive dataset, we have reconstructed the phylogeny of the Podarcis wall lizards in the Balkans, and re-investigated the taxonomic status of the P. tauricus species subgroup. Multilocus analyses revealed that the aforementioned subgroup consists of five major clades, with P. melisellensis as its most basal taxon. Monophyly of P. tauricus sensu stricto is not supported, with one of the subspecies (P. t. ionicus) displaying great genetic diversity (hidden diversity or cryptic species). It comprises five, geographically distinct, subclades with genetic distances on the species level. Species delimitation approaches revealed nine species within the P. tauricus species subgroup (P. melisellensis, P. gaigeae, P. milensis, and six in the P. tauricus complex), underlining the necessity of taxonomic re-evaluation. We thus synonymize some previously recognized subspecies in this subgroup, elevate P. t. tauricus and P. g. gaigeae to the species level and suggest a distinct Albanian-Greek clade, provisionally named as the P. ionicus species complex. The latter clade comprises five unconfirmed candidate species that call for comprehensive studies in the future.

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Why does the neutral theory, which is based on unrealistic assumptions, predict diversity patterns so accurately? Answering questions like this requires a radical change in the way we tackle them. The large number of degrees of freedom of ecosystems pose a fundamental obstacle to mechanistic modelling. However, there are tools of statistical physics, such as the maximum entropy formalism (MaxEnt), that allow transcending particular models to simultaneously work with immense families of models with different rules and parameters, sharing only well-established features. We applied MaxEnt allowing species to be ecologically idiosyncratic, instead of constraining them to be equivalent as the neutral theory does. The answer we found is that neutral models are just a subset of the majority of plausible models that lead to the same patterns. Small variations in these patterns naturally lead to the main classical species abundance distributions, which are thus unified in a single framework.

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The Balearic lizard P. lilfordi inhabits the Gymnesies Islands and have sexual dimorphism. By means of biometric studies and analyses such as the discriminant analysis, it has been determined the morphometric characters that determine this sexual dimorphism. The characters chosen by the analysis were: body length, pileus width, number of gular scales, length of the four finger of the posterior leg. The differential measures of these characters makes the males to have a burlness and robustness greater than the females of the same population. Nevertheless, it cannot be said that in all P. lilfordi populations, the males will be aways the most burliness and robustness,but this will depend upon th population of P. lilfordi we take into consideration.

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Comparisons among eight populations of Podarcis lilfordi, seven of Podarcis pityusensis (representative lizards of the Balearic Archipielago), and one of Podarcis hispanica atrata fro the Columbretes Islands, have been made from a morphological point of view, measuring 15 morphometric characters of the lizards. Cluster and discriminant analyses were obtained for males and females to show the relationships among the different populations and species. These analyses gave three groups: one of them with the most P. lilfordi populations, other with the most P. pityusensis populations, and a well seperated group with the P. hispanica atrata species. Some populations connect the groups of P. lilfordi and P. pityusensis. The possibility that P. lilfordi and P. pityusensis be two pattern of variation inside the same species instead of two well differentiated species is considered, altrough further studies are necessary.

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A major task related to conservation is to predict if planned infrastructure projects are likely to threaten biodiversity. In this study we investigated the potential impact of planned infrastructure in Spain on amphibian and reptile species, two highly vulnerable groups given their limited dispersal and current situation of population decline. We used distribution data of both groups to identify areas of high herpetofauna diversity, and compared the locations of these areas with the locations of the planned road, high-speed train railway and water reservoir network. Four criteria were used for this identification: species richness, rarity, vulnerability, and a combined index of the three criteria. From a total of 1441 cells of 20!20 km, areas of high diversity were defined as those cells whose ranked values for the different criteria included either all species or all threatened species. The combined index provided the smallest number of cells needed to retain all threatened species (1.7 and 2.6% of the cells for amphibian and reptile species, respectively). Coincidences between these high diversity areas and cells including planned infrastructures - denominated - alert planning units - were 35.4% for amphibians and 31.2% for reptiles. Mitigation of the potential impacts would include actions such as barriers to animal access to roads and railways and ecoducts under these constructions. Our approach provides conservation authorities information that can be used to make decisions on habitat protection. A technique that identifies threats to herpetofauna before they occur is also likely to improve the chance of herpetofauna being protected.

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Aim: In this study we tested the hypothesis that the dispersal success (estimated here as fruit removal rate) of a native shrub species living in the Balearic Archipelago, Cneorum tricoccon L. (Cneoraceae), has decreased significantly in those islands where endemic lizards of the genus Podarcis have disappeared. These lizards acted as the main seed dispersers of the plant and became extinct after the introduction of carnivores. At least one of these carnivores, the pine marten (Martes martes L.), is also an important frugivore, consuming the fruits and dispersing the seeds of C. tricoccon and thus allowing the comparison of fruit removal rates between the two groups of vertebrates (lizards and mammals). We further tested the possibility that lizards (in particular, Podarcis pityusensis Bosca) could be exerting selection on seed size. Methods: In seven populations from four islands, we monitored fruit removal by either lizards or mammals. The fruits of C. tricoccon do not drop after ripening, remaining attached to the branches for long periods if not removed. In order to test whether lizards might be exerting selection on seed size, we compared seed diameter and weight between defecated and uningested (collected directly from plants) seeds for each of the populations. Results: Fruits were removed in significantly greater proportions in those populations where lizards are still present. Data showed that in two of the examined populations in the Pityusic islands, defecated seeds were lighter and smaller than controls suggesting that lizards selected fruits of smaller size than the average of the population. Main conclusions: The introduction of carnivores in the Balearics has led to important changes in the population dynamics of many native species. In the larger islands (Mallorca and Menorca), carnivores seemed to have caused the extinction of endemic lizards who acted as the only dispersers of some plants such as C. tricoccon. Pine martens, in particular, are in turn frugivorous and thus can `replace` to some extent the `lost` seed dispersers. We hypothesize that besides having decreased fruit removal rates in this shrub, these `new` dispersers have modified considerably the distribution of the plant on Mallorca island, as the fossil record shows that lizards lived at low altitudes (<500 m a.s.l.) and the plant can be currently found up to 1000 m a.s.l. Furthermore, preliminary data suggest that lizards might be exerting a selective pressure on seed size. If this is true, this pressure might have been released - or counteracted if carnivores select for fruit size as well - after the extinction of lizards from some islands, which would have important ecological consequences for the plant.

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A Survey about helminthfauna of the Saurians living in Cabrera archipelago, Tarentola mauritanica, Hemidactylus turcicus and Podarcis lilfordi, has been made. Sixteen species of helminths have been found from these hosts: 1 trematode (Paradistomum mutabile), 5 cestodes (Oochoristica gallica, Nematotaenia tarentolae, Diplopylidium acanthotetra larvae, Diplopylidium nolleri larvae, Joyeuxiella pasqualei larvae), 9 nematodes (Skrjabinodon medinae, Skrjabinodon mascomai, Spauligodon paratectipenis, Spauligodon sp., Spauligodon cabrerae, Parapharyngodon bulbosus, Parapharyngodon micipsae, Acuaria sp. larvae, Spirurida gen. sp. larvae) and 1 acanthocephalan (Centrorhynchus sp. larvae). The taxonomy and autoecology of the helminths is studied and the structures of helminth communities are analized. This analysis shows that helminth communities of the Saurians of Cabrera are depauperate, tipically isolationist and conditioned by several biotic characteristics of the hosts.

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The effect of several abiotic and biotic factors (island area, distance from a potential colonizing source, sex, age and diet of the host) on helminth diversity of the endemic balearic lizards Podarcis pityusensis and Podarcis lilfordi caught on small islets of the Balearic islands, has been studied.

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The endemic lacertid lizards of the Balearic Islands, Podarcis pityusensis and Podarcis lilfordi, are carnivorous saurians although vegetable matter is important for them in som islands and peculiar environmental conditions. Nevertheless the analysis of their helminth faunas, showed that the herbivorism of these lacertid lizards is a secondary adaptation.

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The knowledge of the helminth communities of reptiles and their ecological relationships with their hosts are until the present not well known. Some general researches have been made only on American herps (AHO 1990). Recently, ROCA & HORNERO (1991a, 1991b) attempted similar kind of researches from Mediter- ranean insularlizards.

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A survey of the helminth communities of Podarcis pityusensis (Bosca, 1883) and Podarcis lilfordi (Gunther, 1874) (Sauria: Lacertidae) from the Pityusic and Gimnesic islands, respectively, in the Balearic Islands, Spain, was conducted. Both host species harbour similar though not identical helminth infracommunities. An analysis of the patterns of diversity for all helminths revealed that both lizards have depauperate isolationist infracommunities, possibly as a result of factors such as host ectothermy, the simplicity of their digestive canal, low vagility, and generalist feeding.

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There is growing concern that anthropogenic climate change may particularly affect ectotherm groups such as amphibians and reptiles. Effects of anthropogenic climate change were already observed on different levels, ranging from changes in the phenology of individuals to changes in entire populations, their demography and geographic ranges with losses and range gains. Especially the latter is exacerbated by interactions of climate change with existing risk factors such as the spread of patho- gens and invasive species. In extreme cases, species are threatened by extinction, which is most likely in endemic species occupying restricted ranges. In this review, possible future climate change scenarios as well as previous observations and general expectations of climate change induced changes in phenology, demography and bio- geography of amphibian and reptile species are presented. Individual case studies on climate change induced changes in demography of the common lizard as well as possible range shifts in the alpine newt are highlighted, with applied methods being discussed regarding different elements of uncertainty.

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The spatial distribution of plants (and other primarily sessile organisms) depends on the interplay between their ecological requirements and the spatial template set before, during, and after the dispersal process. In the case of animal-dispersed plants, the spatial characteristics of animal behaviour during the seed dispersal process are likely to leave a lasting imprint on plant distribution. Here, we hypothesize that the activity patterns of the frugivorous lizard Podarcis lilfordi directly influence the spatial distribution of the fleshy-fruited shrub Daphne rodriguezii. To evaluate this hypothesis, we first analysed lizard activity, following radio-tracked lizards during the plant`s fruiting period, and identified its main determinants at several spatial scales of habitat aggregation (from 12.5 to 150 m). We hypothesised that lizard activity depends on differential habitat features explaining its territory use plus habitat preferences associated with each movement bout. In a second step, the most important determinants of lizard activity plus the variables describing habitat structure were used to predict the presence of adult and juvenile plants. Predictability of lizard activity (based on AUC and Pearson regression coefficients) was higher at broad spatial-scales of habitat aggregation (75 m). The two best predictors of lizard activity were the habitat features of and the distance to the core area (defined as the area enclosing the 0.50 cumulative probability of lizard locations). Plant presence was best predicted by models based on a combination of lizard activity and habitat features at local spatial scales (1.5 m). Best models included habitat features and lizard activity for adult plants, and local-scale habitat features, the proximity of adult plants and lizard activity for juveniles. In both cases, most plants (50–60%) were located at ‘optimal sites’ (both favourable for lizards and with adequate habitat features), whereas a small fraction of them (3–10%) were located at dispersal-limited sites (i.e. with adequate habitat features but suboptimal for lizards). Our results thus suggest that the interplay between lizard activity and local habitat features determines the spatial patterns of juvenile-plant presence and leaves a lasting signature on adult-plant distribution.

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Seed dispersers play a key role in shaping the spatial patterns of plant populations. After their disappearance, we expect a substantial increase in plant aggregation, which can ultimately cascade into high plant competition. We used data of fully mapped distribution of four populations of the shrub Daphne rodriguezii from Menorca Island (Balearic Islands, W Mediterranean Sea), one in which D. rodriguezii coexists with its only disperser, the lizard Podarcis lilfordi, and three populations where this lizard went extinct long ago. We used spatial point-pattern analysis to better understand the lizard`s role on the spatial distribution of D. rodriguezii. To this end, we used specific point-process models that represented our main hypotheses on the impact of (i) habitat suitability, (ii) disperser activity, (iii) proximity of adults on the distribution of juvenile and adult shrubs and (iv) the impact of adult proximity on juvenile survival. Plants were aggregated in all populations, and aggregation at short distances was stronger in populations without lizards. The observed spatial pattern of juveniles was better explained by a combination of hypotheses (ii) and (iii). The density of juveniles below adults was similar in all populations, but density far from adults was higher in the population with dispersers. In populations without dispersers, juveniles suffered higher mortality below adults. Overall, our results suggest that the effects of lizard extinction were subtle. In the absence of lizards` dispersal, plants self-replace in favourable locations, but a decline in density, is evidenced near adults attributed to higher competition. Lizards, which often defecate under fruiting plants, create also a tight juvenile–adult association, but allow juveniles to escape from the immediate proximity of adults attributed to longer-distance movements. Our study shows how the analysis of the spatial pattern of plants can leads to detailed hypotheses on the underlying mechanisms structuring plant populations.

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Seed rain mediated by frugivores is influenced by (1) the seed-deposition distances following fruit ingestion, (2) the disperser activity, as determined by its behaviour and habitat preferences, and (3) the structure of the habitat within the landscape. Here, we evaluated such components using the fleshy-fruited shrub Ephedra fragilis and the frugivorous Balearic lizard Podarcis lilfordi. We estimated seed-deposition patterns based on the displacements and habitat preferences of lizards, derived from visual surveys and telemetry data. The influence of variables potentially determining lizard habitat preference (i.e., height, slope, four measures of habitat abundance and four measures of habitat fragmentation) was evaluated at three spatial scales: ‘home-range’ (c. 2.5–10*103 m2; telemetry data), ‘within home-range’ (c. 100 m2; telemetry data) and ‘microhabitat’ (<100 m2; visual survey). Cumulative lizard displacement (from each telemetric location to the initial capture point) saturated before the peak of seed defecation (seed-retention time), indicating that lizard home-range size and habitat preferences were the main determinants of the spread and shape of seed shadows. Shrub cover was positively correlated with habitat preference at the three scales of analysis, whereas slope was negatively correlated at the home-range scale. Model scenarios indicated that spatially-aggregated seed rain emerged when we incorporated the joint effect of habitat preference at the two largest (home-range and within home-range) scales. We conclude that, in order to predict seed rain in animal dispersed plants, it is important to consider the multi-scale effects of habitat preference by frugivores.

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Mutualistic disruptions, such as those promoted by the loss of seed dispersers, can have negative effects on the plant regeneration of those species that strongly depend upon them. In order to adequately assess how plant communities are affected by such disruptions, we need to know the importance of the dispersal phase, both in its quantitative and qualitative components. We examined this in the narrow interaction between the shrub Daphne rodriguezii and its (only) disperser, the lizard Podarcis lilfordi. We quantified fruit removal and the effect of fruit/seed-size selection, seed treatment in the disperser’s guts and seed deposition patterns on seedling emergence and survival. In the only locality in which lizards persist, they removed most fruits and showed preference for larger ones in one of the two study years. Seed treatment in lizard’s guts had no effect on germination, although it tended to reduce the effect of seed size on germination (differences between large vs. small seeds in seed germination were higher for non-ingested seeds). Probability of seedling emergence, but not survival, was higher in the locality with lizards. Dispersed seeds under heterospecific shrubs showed higher seedling survival than those under conspecifics in all localities, especially the year with higher rainfall. Our findings support that the movement of seeds to nurse shrubs by lizards is the most important component of the seed dispersal process in the only remaining locality where both species coexist.

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Seed dispersal links the end of a plant`s reproductive cycle with the establishment of new recruits. Dispersal over short distances may lead to the local aggregation of individuals, slower population growth and, ultimately, to lower population densities. In this study, we analyse the demographic consequences for the shrub Daphne rodriguezii after the loss of its only seed disperser in an island ecosystem (Menorca Island, western Mediterranean). During a period of 8–10 years, we collected demographic data from five populations, four where the disperser is extinct (disrupted) and the only one in which it still persists (undisrupted). We calculated basic deterministic variables, analysed life table response experiments (LTRE) and their covariation among demographic traits, and simulated future population vulnerability. Population growth rate (λ) was either stable or negative and independent of whether the population was disrupted or not. Current and past population dynamics were similar in the two largest populations (one being the undisrupted), which suggests that the environmental conditions allow them to be stable regardless of seed disperser presence. Variation in λ was dependent on rainfall variability and was highly influenced by stasis and growth. There also existed tradeoffs between the former life traits and fecundity, which indicate strong competition when resources are limiting (e.g. high plant aggregation due to limited seed dispersal or low rainfall), and that could ultimately affect high-elasticity demographic traits. Our study suggests that the population dynamic of D. rodriguezii is stable under the current conditions, and that where dispersal is limiting, important environmental changes (e.g. in habitat suitability and/or rainfall regime) might lead to local extinctions.

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The endangered (CITES II listed) lizard species Podarcis lilfordi Günther, 1874 is en- demic to the Balearic Islands. It is biogeographically unique, in that natural populations are absent from the main islands of Mallorca and Menorca, but present at generally very high densities on many of the tiny coastal rocks, islets and islands that surround them. Analyses using mtDNA sequences have identi ed considerable ne-scale geographical struc- turing (Terrasa et al. 2009), a complete understanding of the signi cance of current subspeci c designations, the occurrence of cross-islet introductions, and the evolutionary history of the dif- ferent forms have been hampered by the relatively slow xation rates of this marker in relation to recency of population vicariance. Markers with many alleles, such as microsatellite loci, have unprecedented ability to detect and describe genetic differences between populations at much smaller geographical scales and time intervals than has traditionally been possible using mtDNA. A panel of fteen microsatellite loci was described for the lizard Podarcis lilfordi, by using enriched genomic libraries for AAAG and ACAG repeat sequence. Characterization of these loci, in 26 individuals within one population (Dragonera’s islet) showed to be highly polymorphic with 6–19 alleles, the observed and expected heterozygosities ranged from 0.46 to 0.92 and 0.78 to 0.95, respectively, and did not deviate from Hardy–Weinberg expectations. These loci were successfully cross-ampli ed in the closely related species P. pityusensis, so these markers will be used to study population differentiation in these species as well as the evolutionary history of different morphological forms.

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Background: Podarcis tiliguerta is a wall lizard endemic to the Mediterranean islands of Corsica and Sardinia. Previous findings of high mtDNA and morphological diversity have led to the suggestion that it may represent a species complex. Here, we analysed mitochondrial and nuclear markers (mtDNA, 3110 bp; 6 nDNA loci, 3961 bp) in P. tiliguerta sampled from thirty-two localities across Corsica and Sardinia. Results: We find much greater intraspecific genetic divergence than between sister species of other Mediterranean island Podarcis, i.e., between P. lilfordi and P. pityusensis. We detected three mtDNA clusters in Corsica (North, South-East and South-West) and either two or three in Sardinia (North vs. South) depending on the clustering method. Only one or two nDNA groups were identified within each main island (again, depending on the method). A Bayesian time- calibrated multispecies coalescent tree was obtained from mtDNA and provided statistical support for a Miocene origin of the species (13.87 Ma, 95% HPD: 18.30–10.77 Ma). The posterior mean divergence time for the Corsican and Sardinian lineages was 12.75 Ma ago (95% HPD: 16.94–9.04 Ma). Conclusion: The results support the evolutionary distinctiveness of Corsican and Sardinian populations and also indicate a lack of post-divergence migration despite periods of contact being possible. Further to this, species delimitation analyses of Corsican and Sardinian lineages provided statistical support for their recognition as distinct (sister) taxa. Our results provide new insights into the biogeography of the Mediterranean biodiversity hotspot, and contribute important findings relevant to the systematics and evolution of this speciose lizard genus.

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A number of the subspecies were studied over several visits to Formentera and Ibiza. Podarcis pityusensis pityusensis is found on Ibiza. However, several animals of different colours were found not all of which conformed to the for that island described subspecies. Furthermore, on Formentera different forms of Podarcis pityusensis formenterae were observed. Three hybrids resulting from a cross between a male Podarcis lilfordi giglioli (Sa Dragonera) and a female Podarcis pityusensis formenterae were born under terrarium conditions. These hybrids proved to be fertile, after mating with Podarcis lilfordi lilfordi (Illa de l`Aire) males these three females laid 12 eggs. Due to a number of circumstances only one egg hatched but a normal young was produced. The various forms of Podarcis pityusensis are found not only on small islets but also on the main islands. Their presence seems to be dependent on the substrate. The hybrids and the various forms of Podarcis pityusensis on the main islands makes it questionable whether the classification of these animals into a great number of subspecies, or even into two species, is justified.

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Recently isolated populations offer a good biological model to infer the evolutionary forces responsible for the current divergences across populations. We coupled genetic, morphometric, ecological, and demographic analyses from three island populations of the endemic Balearic Wall Lizard, Podarcis lilfordi, (Balearic archipelago, Spain) to infer the mechanisms underlying the observed differences in body size. For each population, we described plant community structure, derived a biotic capacity index, and used individual-based data on 1369 lizards captured and released during 6 yr (2009–2015) to estimate population density and body growth patterns. We used genetic data collected on 80 individuals (∼27 for each population) to infer genetic divergences across islets and population history. Body size divergences cannot be explained by the ecological or population characteristics. Individual growth was slower in the smallest island, where lizards reached the largest average body size. In addition to having the highest density, results suggested that resource availability does not constrain asymptotic body size, but the speed at which individuals reach it does. The Approximate Bayesian Computation used to infer population history from genetic data supported the occurrence of two bottlenecks in the islet with the highest anthropogenic footprint. We emphasize the need to integrate ecological and genetic data and the importance of considering the effects of past human disturbance as an additional force in being able to model present island fauna.

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The body growth rate in small reptiles is modulated by per-capita food resources and recent evidences suggested that this constraint is the mechanism underlying differences between cohorts. Per-capita food resources depend on population size and climatic factors but their relative role in explaining the variations in growth rate is unclear. We used morphological data collected over six years to model the body growth of an insular lizard (Podarcis lilfordi Günter, 1874). We used non-linear equations to describe the appropriate length-at-age relationship. For each sex, seasonal growth was observed and the oscillatory Von Bertalanffy curve was fitted to the data. Three age classes were recognized, and we investigated the relative role of density, spring rainfall and temperature in explaining the variation of the growth rate in each sex-by-age class. Results showed that the relative role of density and climatic factors varied according to the age considered. While population size and temperature had a negative effect in the growth rate of juveniles, rainfall had a positive influence for the growth of sub-adults. Adult growth was near zero and constant over time. The different role of density-dependent and climatic factors in explaining age-dependent growth rate provides an important insight in understanding lizard population dynamics and life-history tactics.

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In many species with continuous growth, body size is an important driver of life-history tactics andits relative importance is thought to reflect the spatio-temporal variability of selective pressures.We developed a deterministic size-dependent integral projection model for 3 insular neighboringlizard populations with contrasting adult body sizes to investigate how size-related selective pres-sures can influence lizard life-history tactics. For each population, we broke down differences inpopulation growth rates into contributions from size-dependent body growth, survival, and fecund-ity. A life table response experiment (LTRE) was used to compare the population dynamics of the 3populations and quantify the contributions of intrinsic demographic coefficients of each populationto the population growth rate (k). Perturbation analyses revealed that the largest adults contributedthe most to the population growth rate, but this was not true in the population with the smallestadults and size-independent fertility. Although we were not able to identify a single factor respon-sible for this difference, the combination of the demographic model on a continuous trait coupledwith an LTRE analysis revealed how individuals from sister populations of the same species followdifferent life strategies and showed different compensatory mechanisms among survival, individ-ual body growth, and fertility. Our results indicate that body size can play a contrasting role even inclosely-related and closely-spaced populations.

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Insular animals undergo a serie of behavioural and morphological changes promoted by the isolated character of the populations that are commonly listed under what is known as the ‘island syndrome’. Among these changes there is an increased survival, a lower growth rate and a lower fecundity compared with their mainland counterparts. The ‘island syndrome’ has been proved in mammals and birds, however whether lizards undergo a similar set of changes is a matter of debate. We used individual-based data collected using photoidentification techniques over ten years in two island populations of an endemic lizard inhabiting the Balearic archipelago, and estimate size dependent survival and the somatic their growth parameters. However, a measure of fertility cannot be obtained directly in the field. We used part of the data to estimate sizedependent functions and another part of the data to build a vector of lizard counts. These two set of data were used to couple an Integral Projection Matrix (IPM) with an Integrated Population Model (IPM) into an Integrated Integral Projection Model (IPM2), to estimate fertility as a latent parameter in each population. In the smallest island, population counts fluctuate little (population growth rate near stability: lambda~0.97) and the average annual survival was high. In agreement with the island syndrome, the model delivered a low estimate of fertility. In the second island, however, the population was characterized by large fluctuations with a population growth rate between 1.7 and 0.5). Contrary to the expectations the survival probability was lower and the percapita fertility higher. The population distribution was dominated by hatchlings and subadults while in the first population it was mainly made by adults. We took advantage of the integral and integrated modelling to estimate percapita fertility and showed that individuals in isolated population might exhibit very different strategies.

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Biodiversity loss, including the decrease of diversity of ecological interactions, is known to reduce the capacity of ecosystems to cope with the effects of global change. Here we assessed whether the distribution and survival of two declining relict plant species, Daphne rodriguezii and Cneorum tricoccon, were affected by the mutualism disruption with their only seed-disperser and by climatic and habitat conditions. Due to the lack of data on demographic rates, we used an indirect approach to test these hypotheses. We used presence–absence data as response variables and took two distinct sets of predictors (i.e. habitat and topoclimatic conditions), which were hypothesized to be the main determinants of the demographic rates under question. With these two datasets we fitted species distribution models by means of MaxEnt. Such models were later used to build Combined Species Distributions Models (CM). For each plant species, these CM allowed evaluating the role of both climatic and non-climatic factors, such as the mutualism disruption. Results showed that both climate and habitat conditions determined the current distribution of the two species at a landscape scale. Additionally, the mutualism disruption between C. tricoccon and its native seed-disperser affected plant distribution, moving it to areas where a new alien disperser was present. This alien disperser modified the pattern of habitat selection by plants in terms of habitat quality, reducing their presence in suboptimal areas, which might be the determinant for their survival. Our findings highlight the need of a better understanding of the role of mutualisms within natural communities in order to undertake appropriate conservation actions on threatened plant populations. Furthermore, acting on key factors affecting plant–disperser disruptions (e.g. controlling invasive species) might help to mitigate the effects of global change on declining relict plants.

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In the last two decades, different species of Ophidia from the Iberian Peninsula have arrived in the Balearic Islands. In Mallorca, due to the ancient introduction of the false smooth snake (Macroprotodon mauritanicus) and the viperine water snake (Natrix maura), snakes are not listed as invasive species. Currently, three species of snakes have been recently introduced in Mallorca: the horseshoe snake (Hemorrhois hippocrepis), the ladder snake (Zamenis scalaris) and the Montpellier snake (Malpolon monspessulanus). Even though the latter has a reduced distribution, it generates greater social alarm due to its large size, its appearance and behaviour. In 2018, Servicio de Sanidad y Control de Fauna del Consorcio para la Recuperación de Fauna de las islas Baleares in collaboration with Servicio de Protección de Especies of Conselleria de Medi Ambient i Territori started the first campaign to control introduced Ophidia in Mallorca. In the case of the Montpellier snake, there were only some sighting data and some unusual captures by Centro de Recuperación de Fauna Silvestre of COFIB. With these data, the first campaign was initiated in the municipality of Alcudia, where the highest number of warnings and captures coincided. The aim of this campaign was: (1) to confirm its establishment, (2) in case its presence was confirmed, to assess the need to control. 35 traps were distributed and 29 specimens were captured in 6067 days of trapping. So, not only was its presence confirmed in this area, but the need for control was shown. In the following campaigns, 41, 33, 18 and 38 specimens have been captured during the years 20192022, respectively. These data confirm the presence of a stable population of Montpellier snake in this area of Mallorca. During these years the campaigns have focused on: (1) reducing the density of snakes, (2) improving the knowledge of the distribution area, (3) to manage all the notified sightings of this species. Thanks to this last point, the presence of the Montpellier snake has been confirmed in other municipalities of Mallorca, and in some cases, this is correlated with the movement and importation of ornamental trees. A better knowledge of the Montpellier snake’s distribution and interaction with the environment is essential to adjust the management tools used in the forthcoming years.

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Animal density, despite being conceptually simple, it is one of the most difficult parameter to measure in the field. We compared density estimates of a lizard, Podarcis lilfordi derived by line transects with those from a simultaneous capture–recapture study in three islands of the Balearic archipelago (Spain). The two methods delivered similar results but have different pitfalls and advantages. Line-transects provided a fast and economic method, but density estimates changed over space and time. On the other hand capture-recapture techniques were time consuming, but estimates were similar over the sampling days and showed lower variances.