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Relationships of lacertid lizards were assessed on the basis of 84 primary and 112 binary characters drawn mainly from morphology, including features of the skeleton, external anatomy, various internal soft part systems and two aspects of behaviour. Among features not previously used, or not fully investigated before, are structure of the septomaxilla and nasal passages, arranged of the xiphisternal cartilages, mite pockets, kidney position, ulnar nerve arragement, thoracic fascia, aspects of the hemipenis and its associated muscles, female genitalia and jaw muscles. On the basis of parsimony analysis and compatibilty treatment of this character set, the Lacertidae fall into two main portions: A paraphyletic Palaearctic and Oriental group of primitive forms, from which is derived a holophyletic assemblage of Ethiopian and advanced Saharan and Eurasian taxa. The former group ist not fully resolvable, but Psammodromus and Gallotia appear to be sister groups and are probably related to Lacerta parva and L. fraasi and then L. brandtii, Podarcis appears to be related successively to L. andreanszkyi, the sister species L. dugesii and L. perspicillata, and perhaps L. danfordi and L. laevis. This assemblage may be related to archaeolacertas and Algyroides. The separation of Lacerta lepida, L. pater and L. princeps from the agilis group, based on chemical evidence, is weakly contradicted by morphology. Takydromus may be most closely related to L. vivipara, and L. jayakari and L. cyanura constitute the most likely sister group of the Ethiopian and advanced Saharo-Eurasian assemblage. Taxe in the Ethiopian and advanced SaharoEuroasian assemblage form a long essentially pectinate tree with relatively change between the side branches, except for a strong disjunction separating the more primitive from the more advanced taxa. Most of the former fall on two main branches, with ´Lacerta` australis and ´L.` rupicola possibly basal to them. 1. the Equatorial forest group containing Gastropholis, Bedriagaia, ´Lacerta` echinata, Adolfus, ´Lacerta` jacksoni and Holaspis. The first three of these constitute a holophyletic group and the same is probably true of the remainder. 2. Tropidosaura, Poromera and Nucras, the latter being the sister group of the more advanced forms. These include successively the Ethiopian Philochortus, Latastia, Ichnotropis and Heliobolus, Pseuderemias, Meroles and Aporosaura, and Pedioplanis, and then the Saharo-Eurasian Eremias, Acanthodactylus, Mesalina and Ophisops-Cabrita. It seems probable that the ancestors of modern Lacertidae arose in western Eurasia, where the family is known since the Palaeocene and is still represented there largely by quite primitive forms (89 species and seven nominal genera). The family later invaded Africa, perhaps first in the early or middle Miocene. Relatively primitive lacertids spread widely in largely mesic situations in the Ethiopian region, radiating to some extent (six present genera and 16 species) and producing Nucras and the related series of advaned groups (eight genera and 54 species) whoich show increasing adaptation to xeric environments. These genera tend to have heir most primitive species in the northeast and north of the Ethiopian region. The most advaned gave rise to the Saharo-Eurasian clade, now made up to Eremias, Acanthodactylus, Mesalina and Ophisops-Cabrita. This invaded the arid areas of North Africa and Eurasia, where it is presently represented by 70 species. Many morphological changes in increasingly advanced lacertids may be functionally related to the problems of survival in arid, hot, open environments. Considerable ecological parallelism exists in lacertids, with members of separate stocks occupying similar niches in different geographical areas. Morphological adaptations associated with these niches contribute significantly to the high levels of character homoplasy found in the family. There is also some correlation between the degree of niche differentiation in various groups and the quality of the phylogenies that can be produced from their physical characters. A number of morphological parallels exist between advaned lacertids and New World macroteiids. In the skull at least, advaned lacertids show a complex mixture of paedomorphosis and acceleration. Nomenclatorial changes are as follows: Cabrita is synonymised with Ophisops, necessitating a new name, Ophisops nictans, for Cabrita jerdonii. Aporosaura is synonymised with Meroles, Platyplacopus with Takydromus, and Bedriagaia with Gastropholis. ´Lacerta` (or Centromastyx) echinata is also transferred to the latter genus and Lacerta jacksoni to Adolfus. ´Lacerta` australis and ´L.` rupicola are put in a new genus, Australolacerta. It is recommended that Lacerta dugesii and L. perspicillata should not be placed in the otherwise very uniform genus Podarcis. Although clearly paraphyletic, Lacerta s. lat. Should be retained at least for the present and, if necessary putative relationships within it indicated by informal groups or subgenera.

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Differences in surface structure (ober- hautchen) of body scales of lacertid lizards involve cell size, shape and surface profile, presence or absence of fine pitting, form of cell margins, and the occurrence of longitudinal ridges and pustular projections. Phylogenetic information indicates that the primitive pattern involved narrow strap-shaped cells, with low posteriorly overlapping edges and relatively smooth surfaces. Deviations from this condition produce a more sculptured surface and have developed many times, although subsequent overt reversals are uncommon. Like variations in scale shape, different patterns of dorsal body microornamentation appear to confer different and conflicting performance advantages. The primitive pattern may reduce friction during locomotion and also enhances dirt shedding, especially in ground-dwelling forms from moist habitats. However, this smooth microornamentation generates shine that may compromise cryptic coloration, especially when scales are large. Many derived features show correlation with such large scales and appear to suppress shine. They occur most frequently in forms from dry habitats or forms that climb in vegetation away from the ground, situations where dirt adhesion is less of a problem. Microornamentation differences involving other parts of the body and other squamate groups tend to corroborate this functional interpretation. Microornamentation features can develop on lineages in different orders and appear to act additively in reducing shine. In some cases different combinations may be optimal solutions in particular environments, but lineage effects, such as limited reversibility and different developmental proclivities, may also be important in their genesis. The fine pits often found on cell surfaces are unconnected with shine reduction, as they are smaller than the wavelengths of most visible light.

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New and additional distribution records are given for 12 amphibian, 25 lizard, one amphisbaenian, and five snake taxa from the Cape Province, South Africa. Some of the new records represent large range extensions, whereas others fill in gaps or confirm the occurrence of taxa in the region.

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Acanthodactylus arabicus, Acanthodactylus aureus, Acanthodactylus bedriagai, Acanthodactylus blanci, Acanthodactylus blanfordii, Acanthodactylus boskianus boskianus, Acanthodactylus boskianus asper, Acanthodactylus boskianus euphraticus, Acanthodactylus boueti, Acanthodactylus busacki, Acanthodactylus cantoris, Acanthodactylus dumerili dumerili, Acanthodactylus dumerili exiguus, Acanthodactylus erythrurus erythrurus, Acanthodactylus erythrurus belli, Acanthodactylus erythrurus lineomaculatus, Acanthodactylus felicis, Acanthodactylus gongrorhynchatus, Acanthodactylus grandis, Acanthodactylus guineensis, Acanthodactylus haasi, Acanthodactylus longipes, Acanthodactylus maculatus, Acanthodactylus masirae, Acanthodactylus micropholis, Acanthodactylus opheodurus, Acanthodactylus orientalis, Acanthodactylus pardalis, Acanthodactylus robustus, Acanthodactylus savignyi, Acanthodactylus schmidti, Acanthodactylus schreiberi schreiberi, Acanthodactylus schreiberi syriacus, Acanthodactylus scutellatus scutellatus, Acanthodactylus scutellatus hardyi, Acanthodactylus spinicauda, Acanthodactylus tilburyi, Acanthodactylus tristrami, Acanthodactylus yemenicus, Adolfus africanus, Adolfus alleni, Adolfus jacksoni, Adolfus vauereselli, Algyroides fitzingeri, Algyroides marchi, Algyroides moreoticus, Algyroides nigropunctatus nigropunctatus, Algyroides nigropunctatus kephallithacius, Australolacerta australis, Australolacerta rupicola

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A checklist of the lizards of the Cape Province, South Africa is presented. A total of 143 species and subspecies is recognized. The taxonomic status of no less than 84 (59,1%) of these has changed since the last review of the Cape lizards by FitzSimons (1943). Comments on the distribution and taxonomic status of problematic groups are included.

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Southern Africa has the richest reptile diversity in Africa, with a fauna that currently exceeds 490 species. Present rates of discovery, which for lizards are still comparable to those in the early phases of exploration, indicate that the fauna may approach, if not exceed, 600 species. Lizards form the dominant component (60.9%) of the reptile fauna. The 578 recognised taxa (species and subspecies) were described by 101 authors, of which 12 authors were responsible for 12 or more taxa and together named 68.9% of the total taxa. The five most productive authors were, in order: A. Smith, W. Peters, D. Broadley, J. Hewitt, and V. FitzSimons. The contributions of these authors, the growth in herpetological studies in the last 25 years, and the importance of regional surveys in the development of biogeographic models, are summarised. Over 50 species of reptile have very restricted distributions (less than 3 quarter-degree grid squares) and may be of conservation concern. Despite national rhetoric evincing concern for the biodiversity crisis, there has been a recent decline in herpetological posts and manpower.

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The phenotype of an individual has often been used as the descriminating factor in distinguishing species. However, with the advent of more precise molecular techniques, the genotype of species is increasingly being used as the preferred method in taxonomic classifications. Many taxa have recently been demonstrated to be incongruent in terms of their genetic and morphological groupings, and this may due to the influence that the environment may have on the morphological and functional aspects of a species. Selective pressures often act upon the performance of a species within a particular habitat first, and then selection for the morphological characters that allow for optimal performance occurs. Should genetically disparate species inhabit a particular environment, convergence in morphologies and performance may evolve. Historically, lizard species descriptions were based primarily on external morphologies, and thus misclassfication of species may have occurred due to mistakenly grouping species with convergent morphologies together. In the current dissertation, the links between morphology, performance capacities, diet and behaviour is explored in comparison to the environment and genetic relationships of southern African lacertid lizards. The performance capacities and associated morphological traits were expected to be more closely linked with the environment, and not closely linked with genetic relationships. To investigate these expectations, a multidisciplinary approach was taken, and genetic, morphological and performance analyses were done and compared with dietary behavioural and environmental analyses. In the first chapter, the link between habitat openness and the lizard bauplans is investigated and the presence of convergent morphologies within this group of lizards is uncovered. These convergences are shown to have resulted in misclassification of two lacertid species, and taxonomic revisions within the family are discussed. The second chapter explores the link between performance and associated morphological traits, and the dietary composition of the members of the Nucras genus. The third chapter identifies the link between the predator escape strategies employed by the members of the Meroles genus, and their morphologies and performance capacities. The fourth chapter explores the intraspecific, inter-population differences in morphologies and investigates the link between the morphological groupings and the population genetic groupings within Pedioplanis lineoocellata. The final chapter identifies whether adaptation to a novel habitat can occur over a relatively short period of time, and the morphological traits, functional aspects, and population genetic structure is investigated in conjunction with environmental analyses of vegetation and substrate between the populations of Meroles knoxii. It was concluded that the morphological and functional aspects of the southern African lacertid lizards are more closely related to the environment, particularly the microhabitat structure, than to their genetic relationships, and that future work using this group of lizards should involve a multidisplinary approach as different selective pressures are playing a role in shaping the morphologies and performance capacities of these lizards, compared to those that are acting upon the genotypes of the lizards.

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Molecular phylogenetic analyses of southern African lacertid lizards (Eremiadini) using mitochondrial and nuclear markers revealed two examples of generic assignments incompatible with monophyletic clades. Australolacerta Arnold 1989, a genus endemic to South Africa and to which two isolated species have been referred, is paraphyletic at the generic level. In addition, the species Ichnotropis squamulosa Peters 1854 was found to be embedded within the genus Meroles. To resolve the paraphyly in Australolacerta we erect a new genus, Vhembelacerta Edwards, Branch, Herrel, Vanhooydonck, Measey, & Tolley, gen. nov., to accommodate Lacerta rupicola FitzSimons 1933. To maintain a monophyletic Ichnotropis Peters 1854, Ichnotropis squamulosa Peters 1854 is transferred to Meroles Gray 1838, now named Meroles squamulosus comb. nov. Where necessary the genera affected by these actions are re-characterized.

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Convergent evolution can explain similarity in morphology between species, due to selection on a fitness-enhancing phenotype in response to local environmental conditions. As selective pressures on body morphology may be strong, these have confounded our understanding of the evolutionary relationships between species. Within the speciose African radiation of lacertid lizards (Eremiadini), some species occupy a narrow habitat range (e.g. open habitat, cluttered habitat, strictly rupicolous, or strictly psammophilic), which may exert strong selective pressures on lizard body morphology. Here we show that the overall body plan is unrelated to shared ancestry in the African radiation of Eremiadini, but is instead coupled to habitat use. Comprehensive Bayesian and likelihood phylogenies using multiple representatives from all genera (2 nuclear, 2 mitochondrial markers) show that morphologically convergent species thought to represent sister taxa within the same genus are distantly related evolutionary lineages (Ichnotropis squamulosa and Ichnotropis spp.; Australolacerta rupicola and A. australis). Hierarchical clustering and multivariate analysis of morphological characters suggest that body, and head, width and height (stockiness), all of which are ecologically relevant with respect to movement through habitat, are similar between the genetically distant species. Our data show that convergence in morphology, due to adaptation to similar environments, has confounded the assignment of species leading to misidentification of the taxonomic position of I. squamulosa and the Australolacerta species.

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Eremiadinae, one of three subfamilies of Lacertidae, are distributed throughout Asia and Africa. Previous phylogenetic studies suggested that one of the main groups of Eremiadinae (the Ethiopian clade) consist of two clades with predominately East-African and South-African distribution. Yet, especially the latter one, which includes the genera Pedioplanis, Meroles, Ichnotropis, Tropidosaura and Australolacerta, was not well supported in the molecular phylogenetic analysis. In this study, we analysed the phylogenetic relationships among the genera of the ‘South African clade’ to assess whether this group actually forms a highly supported clade and to address questions concerning the monophyly of the genera. We sequenced sections of the widely used mitochondrial genes coding for 16S rRNA, 12S rRNA and cytochrome b (altogether 2045 bp) as well as the nuclear genes c-mos, RAG-1, PRLR, KIF24, EXPH5 and RAG-2 (altogether 4473 bp). The combined data set increased the support values for several nodes considerably. Yet, the relationships among five major lineages within the ‘South African clade’ are not clearly resolved even with this large data set. We interpret this as a ‘hard polytomy’ due to fast radiation within the South African lacertids. The combined tree based on nine marker genes provides strong support for the ‘South African Clade’ and its sister group relationship with the ‘East African Clade’. Our results confirm the genus Tropidosaura as a monophylum, while Ichnotropis is paraphyletic in our trees: Ichnotropis squamulosa appears more closely related to Meroles than to Ichnotropis capensis. Furthermore, the monophyly of Meroles is questionable as well. Based on our results, I. squamulosa should be transferred from Ichnotropis into the genus Meroles. Also, the two species of Australolacerta (A. australis and A. rupicola) are very distantly related and the genus is perhaps paraphyletic, too. Finally we propose a phylogeographical scenario in the context of palaeoclimatic data and compare it with a previously postulated hypothesis.

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Climatic conditions changing over time and space shape the evolution of organisms at multiple levels, including temperate lizards in the family Lacertidae. Here we reconstruct a dated phylogenetic tree of 262 lacertid species based on a supermatrix relying on novel phylogenomic datasets and fossil calibrations. Diversification of lacertids was accompanied by an increasing disparity among occupied bioclimatic niches, especially in the last 10 Ma, during a period of progressive global cooling. Temperate species also underwent a genome- wide slowdown in molecular substitution rates compared to tropical and desert-adapted lacertids. Evaporative water loss and preferred temperature are correlated with bioclimatic parameters, indicating physiological adaptations to climate. Tropical, but also some popu- lations of cool-adapted species experience maximum temperatures close to their preferred temperatures. We hypothesize these species-specific physiological preferences may con- stitute a handicap to prevail under rapid global warming, and contribute to explaining local lizard extinctions in cool and humid climates.

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The evolutionary diversification of many terrestrial vertebrate groups is strongly linked to climatic events in the Cenozoic, the period from 65 Million years ago to today when modern animals first appeared. I investigated the effects of Cenozoic climate change on the taxonomic and morphological diversification of the Old World lizard family Lacertidae, with particular emphasis on the African radiation. African lacertids exhibit an unusual pattern of diversification, in which their highest species richness occurs in deserts north and south of the equator, despite being spread throughout the continent. This disparity is particularly surprising given that desert lacertids are thought to be evolutionarily younger than their mesic-dwelling relatives, suggesting increased diversification rates in arid habitats. To identify the evolutionary factors underlying this pattern, I use a combination of phylogenetic, morphological and ecological techniques. In Chapter 1, I apply Bayesian methods and fossil-based calibrations to molecular sequence data to construct a time-calibrated phylogeny for Lacertidae. I estimate that the family arose in the early Cenozoic, with the majority of their African radiation occurring in the Eocene and Oligocene. In Chapter 2, I describe changes in lacertid body shape across biomes and substrates, and find widespread morphological convergence in similar habitat types. I suggest that in addition to foraging demands, fluctuating and extreme climatic conditions, largely driven by precipitation and temperature, contribute to morphological convergence across independent arid-dwelling clades. Finally, I test if ancestral transitions in ecology, morphology, and rates of diversification temporally coincide with paleoclimatic events in the Cenozoic. I use High Resolution X-ray Computed Tomography to characterize changes in the skull related to life in arid habitats, and apply maximum likelihood methods to test if the origins of those traits temporally coincide with significant shifts in habitat, diversification rates and climatic changes. My results show that African lacertids experienced three major peaks in diversification, accompanied by the evolution of suites of arid-adapted morphological traits. These changes coincide with climatic shifts in Africa, including the transition from closed forests to open grasslands and savanna in the late Oligocene, prior to the peak temperatures of the mid-Miocene Climatic Optimum, and following the formation of the Benguela current leading to hyper-aridity in southern Africa. I conclude that deserts are important centers for reptile evolution, but that expected changes in climate due to global warming may outpace the ability of arid-dwelling species to adapt and persist in the future.

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Aim To map and assess the richness patterns of reptiles (and included groups: amphisbaenians, crocodiles, lizards, snakes and turtles) in Africa, quantify the overlap in species richness of reptiles (and included groups) with the other terrestrial vertebrate classes, investigate the environmental correlates underlying these patterns, and evaluate the role of range size on richness patterns. Location Africa. Methods We assembled a data set of distributions of all African reptile species. We tested the spatial congruence of reptile richness with that of amphibians, birds and mammals. We further tested the relative importance of temperature, precipitation, elevation range and net primary productivity for species richness over two spatial scales (ecoregions and 1° grids). We arranged reptile and vertebrate groups into range-size quartiles in order to evaluate the role of range size in producing richness patterns. Results Reptile, amphibian, bird and mammal richness are largely congruent (r = 0.79–0.86) and respond similarly to environmental variables (mainly productivity and precipitation). Ecoregion size accounts for more variation in the richness of reptiles than in that of other groups. Lizard distributions are distinct with several areas of high species richness where other vertebrate groups (including snakes) are species-poor, especially in arid ecoregions. Habitat heterogeneity is the best predictor of narrow-ranging species, but remains relatively important in explaining lizard richness even for species with large range sizes. Main conclusions Reptile richness varies with similar environmental variables as the other vertebrates in Africa, reflecting the disproportionate influence of snakes on reptile richness, a result of their large ranges. Richness gradients of narrow-ranged vertebrates differ from those of widespread taxa, which may demonstrate different centres of endemism for reptile subclades in Africa. Lizard richness varies mostly with habitat heterogeneity independent of range size, which suggests that the difference in response of lizards is due to their ecological characteristics. These results, over two spatial scales and multiple range-size quartiles, allow us to reliably interpret the influence of environmental variables on patterns of reptile richness and congruency.

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The albumins from 41 species of the family Lacertidae representing a substantial part of genera as well as infrageneric groups of the collective genus Lacerta s.l. were investigated by means of the MCF technique. The data allow a chronological estimation of the most important radiation events and their correlation with paleogeographical facts. Our results are in remarkable contradiction to the phylogeny presented by ARNOLD (1989a) based mainly on morphological characters. The most important phylogenetic relationships are: 1. The genera Gallona and Psammodromus are already isolated from the other taxa since the Oligocene. We assess these main branches as subfamilies Gallotiinae and Lacertinae. 2. Lacerta s.str. and Lacerta subgenus Zootoca form the sister group of the remaining Lacertinae. 3. A colonization of Africa in the Lower Miocene has led to a separation in two lines, with mainly Eurasian and African members respectively. 4. ARNOLD`S (I.e.) `Ethiopian and advanced Saharo-Eurasian clade` proved to be a paraphyletic unit, one group of genera being more closely related to European taxa. All techniques applied to the systematics of Lacertidae hitherto are critically discussed. An area-time- hypothesis concerning the phylogeny of Lacertidae is presented. Key words: Lacertidae, phylogeny of; Gallotiinae subfam. nov.; Lacertinae subfam. nov.; micro complement fixation; albumin evolution.

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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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Point distribution data were used to evaluate the biogeographical influence of the arid Tankwa Karoo Basin on the distribution of reptiles in the south-western districts of South Africa. Under-representation of the Tankwa Karoo in the dataset required an additional field survey of this region. Prior to the survey, available records from the Tankwa Karoo Basin represented only 13 reptile species. A total of 36 species (24 lizards, nine snakes, three chelonians) was recorded during our survey of this area. Turnover across the Basin is high, species richness is lower than in surrounding mountainous areas and there are no species endemic to the area. The Tankwa Karoo Basin acts as a dispersal barrier for many reptile species occurring in the surrounding more mesic areas. At the same time, the ranges of a number of typical northern, arid-adapted species extend southward along the Tankwa plains. A number of species range extensions in the region are reported.

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A survey of the lizard fauna of the south-western Cape has provided additional distributional and ecological information on four species formerly listed as threatened. The status of Phyllodactylus microlepidotus , Lacerta australis, Cordylus cataphractus and Scelotes gronovii is reconsidered in the light of the new information. The conservation status of two recently discovered species is also discussed. The authors` present knowledge of the lizard fauna of the Cape Province is considered and recommendations made for sampling methodology in future studies.

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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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The southern rock lizard Australolacerta australis is a rock-dwelling lizard endemic to South Africa. The phylogenetic relationships of this species with other lacertid lizards are still not clear and have never been assessed in any phylogeny of Lacertidae using DNA sequence data. In this study we employed 3 044 base pairs from mitochondrial cytochrome b, 12S and 16S rRNA genes to investigate the phylogenetic position and the evolutionary history of A. australis. We performed phylogenetic analyses under the assumptions of Maximum Likelihood and Bayesian inference and estimated the timing of the cladogenic events related to A. australis by using a relaxed molecular clock method. Our phylogenetic reconstruction clearly placed A. australis within the southern African branch of the tribe Eremiadini including genera Tropidosaura, Meroles, and Pedioplanis. The former genus constitutes with A. australis a clade endemic to southernmost mountains of Africa. The radiation of this southern African clade is estimated to have occurred during the Mid Miocene (14.7

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Locomotion is important to animals because it has direct implications for fitness through its role in predator escape, prey capture, and territory defence. Despite significant advances in our understanding of animal locomotion, studies exploring how substrate properties affect locomotor performance remain scant. In the present study, we explore how variation in substrate (sand, slate, cork) affects locomotor performance in lacertid lizards that differ in morphology. Moreover, we explore whether substrate effects are the same for different types of locomotor performance (speed, acceleration, and stamina). Our results show that the substrate affected most types of locomotor performance studied but not always in the same way. Although substrate effects were species-dependent for the maximal speed over 50 cm and the distance run to exhaustion, this was not the case for acceleration capacity. These results suggest that substrate texture differentially affects burst performance vs. longer duration measures of locomotor performance. Finally, straightforward relationships between habitat use and the substrate on which performance was maximized were not observed. This suggests that the evolution of locomotor capacity is complex and that animals may show compromise phenotypes allowing them to deal with a variety of substrates in their natural environment.