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Secondary seed dispersal is a multistep system that includes 2 or more dispersal processes that can increase the distance from whichseeds arrive. This phenomenon is relatively common in some habitats of subtropical oceanic islands due to the frequent frugivore–predator interactions found in them. In this study, we describe how the Eurasian Kestrel is an effective disperser of plants in thesecondary seed dispersal process, through interaction with frugivorous lizards. Experiments using captive wild kestrels, along withfield data, showed that predation of kestrels on lizards leads to a secondary seed dispersal with 2 possible outcomes: 1) most seeds(89%) are not consumed by kestrels because they reject the lizards’ digestive tracts and so receive only the gut treatment of lizardsand 2) a small fraction of seeds (11%) appeared inside the kestrel pellets as a result of indirect ingestion by this raptor, thusundergoing double gut treatment. So, 2 different seed dispersal distances may result from this interaction: 1) when the kestrelscapture the lizard and transport it to a perch where the seed-containing guts are discarded and 2) when they indirectly ingest a fewseeds from lizards, consequently increasing the dispersal distance. Seeds from the Macaronesian plant speciesRubia fruticosaweretested, finding that those passed through kestrels had a lower germinability than those that remained inside the rejected lizards’digestive tracts, which had similar germination rates to those from control plants (uningested seeds). The kestrel can be consid-ered an important and effective long-distance seed disperser due to the high abundance of frugivorous lizards in their diet, theirstereotyped consumption behavior, and the effectiveness of their seed dispersal.

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Two satellite DNAs (satDNAs) have been isolated and characterized from three populations of Atlantolacerta andreanskyi. One satDNA (AAN‐TaqI) has been isolated here from the first time. It is characterized by a tendency to AT enrichment (AT = 54.2%) and monomer length ranging from 187 to 199 bp. FISH experiments showed that this element occurs in subterminal position on the short arms of all chromosomes of the complement. The analyses of genetic variability of AAN‐TaqI showed that the concerted evolution is acting effectively on these repeats that form separate clusters consistent with the geographic origin in the phylogenetic tree, thus supporting the hypothesis that A. andreanskyi would be a species complex. In addition, in the population from Jbel Aoulime this satDNA is already differentiated into two subfamilies. The other satDNA belongs to the family of IMO‐TaqI already isolated in other lacertids. Differently from AAN‐TaqI, concerted evolution does not seem to act effectively on this element that is not differentiated between populations. These results confirm that IMO‐TaqI (AT = 53.4%) is conserved in both chromosomal position and most of its sequence in the lacertids from which it has been characterized so far. Its remarkable evolutionary conservation for about 45 million years could indicate that this satDNA may have a functional role that future investigations could unveil. Once again, this study shows how satDNAs coexisting in the same genome may differ in their evolutionary pattern, even though the reasons underlying this phenomenon in the species here studied have still to be fully understood.

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A new species, Ophionyssus schreibericolus Moraza sp. nov. is described, based on adult females, males and protonymphal instars. Ophionyssus schreibericolus parasitizes Lacerta schreiberi, a lizard endemic to the Iberian Peninsula, and known to have persisted in refugial populations throughout the Pleistocene. A key to adult females, males and protonymphs of the genus Ophionyssus is presented. Ophionyssus viperae Miron & Ivan 2003 is synonymised with O. natricis (new synonymy).

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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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Some mate choice theories propose that only male signals that are honest and condition-dependent can be stable, while another hypothesis states that males evolve signals that exploit the sensory system of females. However, sensory traps might evolve into honest signals if they are differentially costly for males. We tested whether a pre-existing sensory bias for food chemicals explained chemosensory preferences of female Iberian rock lizards for male scents. We manipulated hunger levels of females and found that food-deprived females had increased chemosensory responses to chemical stimuli from both invertebrate prey and femoral secretions of males, but not to control water. Further tests suggested that cholesta-5,7-dien-3-ol (provitamin D3), a lipid found in both prey and males’ scent, may be one of the chemicals eliciting these responses. Moreover, hungry females spent more time on scent marks of males that had experimentally increased cholesta-5,7-dien-3-ol than on scent marks of males alone, whereas for control females this effect was not significant. We suggest that preexisting sensory bias for essential nutrients (i.e., provitamin D) may be the origin of similar female responses to male chemicals. However, previous studies have suggested that the allocation of these chemicals to ornaments is costly and only high quality males can afford it. Therefore, preexisting sensory bias for essential nutrients may further allow the evolution and maintenance of honest sexual display.

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Prey experience a broad range of temporal patterns of predation risk and may face different problems when assessing risk level and deciding how to allocate costly antipredator behaviour across time. We simulated in the laboratory repeated predatory attacks of different intensity (low versus high risk) to Iberian rock lizards, Iberolacerta cyreni, with similar numbers of low- and high-risk attacks across a trial, but with different temporal patterns of presentation (i.e. a series of low-risk and then a series of high risk, or vice versa, or successive attacks where risk changed randomly). We measured activity levels, time hidden in refuges after each predatory attack, and propensity to hide in refuges when the predator is close but not actually attacking (‘false alarm’ flights). Antipredator responses were of higher intensity when risk was high, but responses also depended on temporal patterns of risk. When previous attacks were of low-risk or when risk was random, prey activity did not change between risk levels. False alarm flights in the low-risk situation were more frequent when risk was random or immediately after a series of high-risk attacks. When successive attacks were of similar risk level, lizards seemed able to predict risk level in the next attack and modified their antipredator behaviour accurately. However, when risk level was random, lizards did not seem able to predict risk level and adopted a conservative strategy, overestimating risk even though costs of the antipredator responses increased.

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Here, we present a case of nocturnal activity of a diurnal Pelasgian Rock Lizard,Anatololacerta pelasgiana (Mertens, 1959) in Çığlıkara Nature Reserve. During our fieldwork in August 2016, we detected the nocturnal behavior individuals on the walls of the fire tower/cabin in the cedar forest. Besides, there is this is the first case of a nocturnal behavior without any artificial light.

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Results of chromosomal and molecular studies of the lizard Zootoca vivipara (Lichtenstein, 1823) (Lacertidae) from many geographically separate populations of Europe and Asia have been generalized. The questions of ka­ryotype differences within the species, of diversity of its Zw and multiple Z1Z2W sex chromosome, their reorganizations and evolutionary consequences have been briefly considered. Stability of forming karyotypes is as an integrating factor which allow to identify the specimens and unite them into the groups possessing the distinct distribution areas. There are a correlation between chromosomal, mt DNA and nuclear DNA data. Finally all data obtained allow to draw a conclusion that Z. vivipara represents a cryptic group of cryptic taxa. Besides new data about the behavior of multiple sex chromosomes (SC, synaptonemal complexes) in early meiosis and molecular-cytogenetic data on transposable elements (TE) in the genome of Z. vivipara, their localization in the definite regions of chromosomes may suggest that they play a role in active speciation process by formation of cryptic taxa.

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The ecological theory of island biogeography suggests that mainland populations should be more genetically divergent from those on large and distant islands rather than from those on small and close islets. Some island populations do not evolve in a linear way, but the process of divergence occurs more rapidly because they undergo a series of phenotypic changes, jointly known as the Island Syndrome. A special case is Reversed Island Syndrome (RIS), in which populations show drastic phenotypic changes both in body shape, skin colouration, age of sexual maturity, aggressiveness, and food intake rates. The populations showing the RIS were observed on islets nearby mainland and recently raised, and for this they are useful models to study the occurrence of rapid evolutionary change. We investigated the timing and mode of evolution of lizard populations adapted through selection on small islets. For our analyses, we used an ad hoc model system of three populations: wildtype lizards from the mainland and insular lizards from a big island (Capri, Italy), both Podarcis siculus siculus not affected by the syndrome, and a lizard population from islet (Scopolo) undergoing the RIS (called P. s. coerulea because of their melanism). The split time of the big (Capri) and small (Scopolo) islands was determined using geological events, like sealevel rises. To infer molecular evolution, we compared five complete mitochondrial genomes for each population to reconstruct the phylogeography and estimate the divergence time between island and mainland lizards. We found a lower mitochondrial mutation rate in Scopolo lizards despite the phenotypic changes achieved in approximately 8,000 years. Furthermore, transcriptome analyses showed significant differential gene expression between islet and mainland lizard populations, suggesting the key role of plasticity in these unpredictable environments.

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Quantification of heavy metal concentrations in biota is a common technique that helps environmental managers measure the level of pollutants circulating in ecosystems. Despite interest in heavy metals as indicators of localized pollution, few studies have assessed these pollutants in reptiles. In 1998, the tailing pond of a pyrite mine near Aznalcóllar (southwestern Spain), containing mud with high heavy metal concentrations, collapsed, releasing 6 million m(3) of toxic sludge into the Guadiamar Basin. Here we analyze heavy metal concentrations in the most common reptile in the area, the large psammodromus, Psammodromus algirus, a rather small lizard. We quantified levels of several elements (Hg, Sb, Cd, Cr, Tl, Sn, Ba, Cu, Pb, Sr, Mn, Rb, As, and Zn) in lizard tail clips collected in and around the affected area during the springs of 2005 and 2006. Samples were collected from two contaminated localities, one directly affected by the spill, and another adjacent to the tailing pond, but not covered by toxic mud. We also collected samples from a nonpolluted control site in the same basin. We found higher concentrations of As, Tl, Sn, Pb, Cd, and Cu in lizards from the affected area than in lizards from the control site, indicating the continued presence of heavy metal pollutants in the terrestrial food chain 8 years after the mine accident. We did not uncover sexual or annual differences in heavy metal concentrations, although concentrations increased with lizard size. We discuss how heavy metals moved across the food chain to lizards, despite intensive restoration efforts after the accident, and suggest that reptiles to be included in biomonitoring programs of heavy metals pollution in terrestrial habitats.

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The scientific biography of the outstanding herpetologist and specialist in zoogeography Sergei Alexandrovich Chernov (1903–1964) was reconstructed on the base the study of archival materials and literature sources. The text is divided into four parts, reflecting the main stages of his biography: 1903–1930 – Kharkiv, the beginning of the scientific career; 1930–1941 – relocation to Leningrad, Tajik-Pamir expedition; 1941–1945 – Great Patriotic War and evacuation; 1945–1964 – period after the Great Patriotic War. In the paper, we emphasize the line of teacher–student continuity begun by A.M. Nikolsky and S.A. Chernov in the herpetology department of the Zoological Institute of the Russian Academy of Sciences. The appendix contains a list of his publications (52 ti- tles), taxa, described by him (11) and named in his honor (6). In majority of his publications, Chernov was the sole author; most of them were published in Russian; only one paper was written in a foreign (German) language. One of the main achievements of Chernov should be recognized a publication of the Guide of amphibians and reptiles of the USSR together with P.V. Terentyev. He made the greatest contribution to the study of the systematics of lizards and snakes, composition, zoogeography, and the history of the formation of the herpetofauna of Central Asia. According to his studies, the fauna of Central and Central Asia are subsidiaries of the once united region, what contradicted the views of his teacher Nikolsky, who developed the concept of M.A. Menzbir about the young postglacial origin of the Aral-Caspian deserts and the ancient, Eocene origin of the deserts of Central Asia.

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The contact zones of the distribution ranges of closely related reptile taxa are the source of valuable data on the microevolutionary processes in populations, the history of regional faunas origin, and the environmental prefer- ences of the studied forms. Our study is focused on the genetic structure of the populations of sand lizard, Lacerta agilis Linnaeus, 1758, at the Crimean peninsula. This lacertid species inhabits the mountain (afforested) and plain (steppe) parts of the Crimea, being abundant or common in many areas. Lacerta agilis is represented in the Crimea by two subspecies: the widely distributed Eastern (L. a. exigua Eichwald, 1831) inhabiting a large part of Northern Eurasia, and the endemic (L. a. tauridica Suchow, 1927) residing in the Crimean mountains. Mitochondrial hap- logroup affiliation corresponding to one of the subspecies (L. a. tauridica, L. a. exigua or L. a. chersonensis) was established for 225 L. agilis individuals from 81 localities in the Crimea and adjacent mainland territories. The nu- cleotide sequences of the complete cytochrome b gene of mitochondrial DNA (1143 bp) were studied in 75 L. agilis individuals from 68 localities. The genetic distance between both subspecies inhabiting the Crimea revealed by used molecular marker comprised 2.8%, which indicates their early divergence approximately at the transition of Early to Middle Pleistocene (ca. 1 Mya). L. a. tauridica is characterized by a comparatively deep genetic structure. Haplotypes occupying isolated positions on the phylogenetic tree of this subspecies were found in the south-west- ern part of the Crimean Mountains, what might be explained by the localization of L. agilis microrefugia in areas least affected by the Late Pleistocene cooling. Genetic structure of L. a. exigua is more homogeneous. Another important result of our study was an identification of zones of haplogroups «exigua» and «tauridica» coexistence localized along the northern and eastern margins of the Crimean Mountains. The portion of the «exigua» hap- logroup in local populations decreases southward and westward. The observed pattern of the spatial distribution of haplogroups seems to be a result of the hybridization zone formation between the sand lizard subspecies during the Holocene expansion of L. a. exigua. Ecological niches modeling for L. agilis subspecies and analysis of morpho- logical variability of the lizards support the hypothesis of L. a. exigua and L. a. tauridica hybridization in the area of contact of their ranges in the eastern part of the Crimean Mountains.

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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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We generated an extensive morphological and multilocus molecular dataset to investigate the taxonomy of Acanthodactylus erythrurus, a widespread species across the Mediterranean and semiarid habitats of the Iberian Peninsula and the Maghreb. Our integrated analyses revealed the existence of at least five basal lineages: (i) an Ibero-Moroccan clade widespread across Morocco and the Iberian Peninsula, from sea-level up to a maximal known altitude of 1,930 m, (ii) an Algero-Tunisian clade, distributed in coastal and inland areas of eastern Algeria and Tunisia, (iii) a Central Algerian clade, formed by two inland populations located in central Algeria (1,000–1,500 m a.s.l.), (iv) a western High Atlas clade including two montane populations from Jbel Siroua and Tizi n’Tichka (at 2,320 m and 2,176 m a.s.l., respectively) and (v) an eastern High Atlas clade, including at least two montane populations from Isli and Tislit (both localities around 2,275 m a.s.l.). An integrated species delimitation approach combining molecular and multivariate morphological analyses demonstrated complete reproductive isolation and hence speciation between the Ibero-Moroccan clade and the eastern High Atlas clade in their contact zone. The divergence between all five clades is broadly similar, supporting the existence of at least five species in the Acanthodactylus erythrurus complex. In the present work we describe the two well-differentiated endemic species from the Moroccan Atlas for which no name is available: Acanthodactylus lacrymae sp. nov. from Isli and Tislit and A. montanus sp. nov. from Jbel Siroua and Tizi n’Tichka. Further work will be needed to fully resolve the taxonomy of this species complex.

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Skrjabinelazia rizzoi n. sp. (Seuratoidea), from Podarcis sicula captured at Cammarata, Agrigento Province, Sicily, is distinct from the 13 known species of the genus, including Skrjabinelazio sp. Rizzo from Catania. It is identified with the following set of characters: in the male, short spicules and gubernaculum, thin body; in the female, buccal cavity with a crown of leaflets, body cuticle without internal ornamentation, presence of cephalic and caudal vesicles, tail with a terminal digitiform spike 42-48 microm long. The morphology of the new species supports our previous hypothesis of two Skrjabinelazia lineages, one with spicules and one without spicules, respectively linked to Lacertidae and Gekkonidae. In Palearctic lacertids, five named species are presently known, S. taurica from Crimea (Ukraine), S. hoffmanni from Beijing (China), S. pyrenaica from Pyrenees (Spain), S. vozae from Cevennes (France), S. rizzoi from Agrigento Province, Sicily (Italy), but analysis of some published works suggests a greater diversity. S. rizzoi infection, found in April-May in 1/5 lizards, was recent with young females in the host`s stomach and intestine, and males in the stomach. One female contained four membranous-shelled eggs. The two other females contained a few hatched infective larvae, membranous-shelled eggs with developing embryos and, unexpectedly at this early stage, a few thick-shelled divided eggs. As in several other Skrjabinelazia species, the progeny of S. rizzoi are adapted for intra-host suprainfection and inter-host transmission, but in this species the production of resistant eggs appears in very young females.

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The age and growth in two breeding populations of A. danfordi, inhabiting altitudes ranging from 678 m a.s.l. to 1200 m a.s.l. in Turkey, were investigated. The age differences between sexes were not statistically significant in either population. The mean age was calculated as 8.73 ± 2.12 and 8.33 ± 1.8 years in Kozan and 7.25 ± 1.58 and 5.78 ± 1.64 years in Saimbeyli for males and females, respectively. The age distributions of males did not statistically differ between populations, but females in Kozan were significantly older than those in Saimbeyli. The mean snout-vent length (SVL) difference between sexes was not significant in the Kozan population, whereas males were significantly longer than females in Saimbeyli. However, SVL was similar between the populations. Intersexual differences in body size were found to be male-biased for both populations. There was a positive and statistically significant relationship between SVL and age in both populations. This study examines the feasibility of the use of skeletochronology for A. danfordi. It also shows that these populations are getting older and this may endanger the future of A. danfordi in a warming world. Some life history parameters and population structures of A. danfordi are provided in this study but some questions still remain.

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The aim of this study was to investigate the histological and fine structure of the liver of Acanthodactylus boskianus during the hibernation period, using ten adult specimens captured from sandy areas of Aswan Governorate, Egypt. Specimens of liver were fixed for light and transmission electron microscope to study the hepatic architecture during this period. In addition to haematoxylin and eosin stain, the histochemical and special stains were used. The hepatocytes are arranged in hepatic plates. The radial arrangement of hepatic cords around the central vein is generally not apparent. The several-cell-thick plate type showed with multi-layered of hepatocytes separated by narrow tortuous capillaries networks, sinusoids that are localized in the space between hepatic plates. The hepatic cells of Acanthodactylus boskianus under light and T.E.M. are similar to those of other vertebrates (birds and mammals), except for the presence of melano- macrophages.

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Movement‐based indices such as moves per minute (MPM) and proportion time moving (PTM) are common methodologies to quantify foraging behavior. Hundreds of studies have reported these indices, many without specifying the temporal resolution of their original data, and others using varying resolutions. This was done despite the likelihood that observation resolution can affect MPM and PTM estimates. Our goal was to empirically determine the sensitivity of these foraging indices to changes in the temporal resolution of the observation. We used a high-speed camera to record movement sequences of 20 Acanthodactylus boskianus lizards. Then, we gradually decreased the resolution of the data and calculated the foraging indices at different temporal resolutions. When considering the range of temporal resolutions that are relevant for field observations with unassisted vision, we found 68% and 48% difference in MPM and PTM estimates, respectively. When using the highest resolution, our estimate of MPM was an order of magnitude higher than all prior reported values for lizards. Our results raise major concerns regarding the use of already published movement-based indices, and enable us to recommend how new foraging data should be collected.

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This papar presents several ways of finding out the number of lizards on a predetermined area. The study took place in a sandy biotope from the sounthern region of Dolj, on an area shaped like a square, measuring about 10000 square meters.

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While running, small animals frequently encounter large terrain variations relative to their body size, therefore, terrain variations impose important functional demands on small animals. Nonetheless, we have previously observed in lizards that running specialists can maintain a surprisingly good running performance on very uneven terrains. The relatively large terrain variations are offset by their capacity for leg adjustability that ensures a ‘smooth ride’ of the centre of mass (CoM). The question as to how the effect of an uneven terrain on running performance and locomotor costs differs between species exhibiting diverse body build and locomotor specializations remains. We hypothesise that specialized runners with long hind limbs can cross uneven terrain more efficiently than specialized climbers with a dorso-ventrally flattened body and equally short fore and hind limbs. This study reports 3D kinematics using high-speed videos (325 Hz) to investigate leg adjustability and CoM movements in two lacertid lizards (Acanthodactylus boskianus, running specialist; Podarcis muralis, climbing specialist). We investigated these parameters while the animals were running on a level surface and over a custom-made uneven terrain. We analysed the CoM dynamics, we evaluated the fluctuations of the positive and negative mechanical energy, and we estimated the overall cost of transport. Firstly, the results reveal that the climbers ran at lower speeds on flat level terrain but had the same cost of transport as the runners. Secondly, contrary to the running specialists, the speed was lower and the energy expenditure higher in the climbing specialists while running on uneven terrain. While leg movements adjust to the substrates’ variations and enhance the stability of the CoM in the running specialist, this is not the case in the climbing specialist. Although their legs are kept more extended, the amplitude of movement does not change, resulting in an increase of the movement of the CoM and a decrease in locomotor efficiency. These results are discussed in light of the respective (micro-)habitat of these species and suggest that energy economy can also be an important factor for small vertebrates.

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Environmental factors may affect animal performance in diverse ways, even among different populations of a single species. Here, we assess the impact of substrate type on the sprint performance (maximum speed and acceleration) of Schreiber’s fringe-fingered lizard (Acanthodactylus schreiberi). This species is a skillful runner that also bears micro spike-like protruding scales on its toepads (toe fringes), an adaptation for locomotion on sand. We worked with three populations living in habitats that differ in substrate type (sand, soil and rock). We measured sprint performance using a race-track with custom substrate platforms replicating the different substrate types. We formulated two hypotheses: first, we anticipated that the three populations would differ in their sprint performance due to the differences in substrate type; second, we expected that each population would perform better on its home substrate. Our results generally refuted the hypothesis that sprint performance would differ on different substrate types. Our results suggest that there is a restricted effect of substrate type on locomotion and indicate a multifactor interplay among alternative underlying parameters.

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Mammals that build extensive open burrow systems are often classified as ecosystem engineers, since they have the potential to modulate the availability of resources for themselves and other organisms. Lizards may benefit from the heterogeneity created by these structures, especially if coupled with an increased offer of sites for refuge and thermoregulation. However, information about these engineering effects by burrowing animals is scarce. We investigated the influence of European rabbit burrows on several parameters of a Mediterranean lizard community (abundance, density, diversity and body condition) in three different habitats (open pastures, holm oak and scrub patches). We found that lizards were positively associated with burrows, and that burrows determined lizard presence at otherwise unfavourable habitats. Moreover, community parameters such as density and species richness were higher in sites with burrows. Burrows influenced lizard species in different ways, and were also relevant for other Mediterranean vertebrates, as revealed by questionnaires to experts. We also explored the possible resources provided by burrows for lizards. Warrens offer relatively abundant prey and appropriate retreat sites for refuge and thermoregulation. Warrens may have further implications within the ecosystem, acting as stepping stones, allowing lizards to reach otherwise inaccessible habitat patches. This study shows that European rabbit warrens have a positive influence on lizard density and diversity, and confirms the role of rabbits as ecosystem engineers. This reinforces the need for appropriate conservation measures for rabbits, especially given their threatened status in the Iberian Peninsula. Furthermore, our study highlights that taking into account the influence of engineering activities increases our awareness of species interactions, and may translate into more adequate conservation measures for the preservation of biodiversity.

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We measured the level of fluctuating asymmetry (FA) in head shape, head scalation and femoral pores in two lizard species (Podarcis bocagei and Podarcis hispanica) from 13 islands and 15 mainland localities in the Ria de Arosa archipelago of north-western Spain. Given the recent geological history of the region, the degree of isolation to which lizard populations have been subjected can be ordered along a spatio-temporal gradient, yielding the following hypotheses to be tested: FA will be higher (1) in island populations than in mainland populations; (2) on remote islands than on islands close to the mainland; (3) on small islands than on large islands. Molecular genetic data suggest that P. hispanica is autochthonous in the Ria de Arosa, whereas P. bocagei is a more recent arrival. Therefore, we predict also (4) a higher level of FA in P. hispanica than in P. bocagei. Statistically significant results were obtained for head-shape asymmetry, supporting the second and the fourth hypotheses. With an overall meristic asymmetry index, none of the hypotheses were corroborated, whereas for certain independent meristic traits, the first, the third and the fourth hypotheses were partially supported. Both head shape and meristic traits constitute precise measures of FA, but FA is more convincingly expressed in head shape and in single meristic traits than in overall meristic traits asymmetry. We conclude that FA reflects population isolation and may be a good indicator of developmental instability. It seems worthwhile to test for FA in a landlocked system under environmental and genetic stress, for the purpose of conservation biological assessments.

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The cytotoxic effects of cadmium (Cd) on the pituitary gland were studied in the lizard Podarcis sicula. Adult lizards were treated intraperitoneally with a single injection of CdCl2 at the dose of 2 mg/kg. A morphological study was performed by terminal deoxynucleotidyl transferase‐mediated dUTP nick end labeling (TUNEL) technique and by immunocytochemical demonstration of caspase‐3 for detecting apoptotic cells in situ after 2, 7, and 16 days of treatment. The pituitary cells of Cd‐treated P. sicula undergo apoptosis: after 2 days the apoptotic cells appeared to increase significantly compared with those of the control specimens; after 7 days there was no considerable increment; however, after 16 days the occurrence of apoptotic cells had increased markedly, above all in the rostral pars distalis (RPD) in which various cells showed a strongly immunostained nucleus by TUNEL. Cd appears particularly toxic for pituitary cells in the lizard P. sicula; a single high intraperitoneal dose of CdCl2 induces apoptosis, in particular in the RPD, and this effect appears irreversible.

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The Viviparous lizard Zootoca vivipara (Lichtenstein, 1823) is widespread across Eurasia, but in Bulgaria it is considered a glacial relict, restricted to the high mountains. In spite of its wide distribution, there is still lack of knowledge on its dietary habits, especially from the southern part of the range. In order to shed light on its diet, we conducted а study in three mountain sites in Bulgaria (Vitosha, Rila and Stara Planina Mtns.). They were visited in 2016 and 2017 during the lizard`s active season (May–September); 343 Viviparous lizards were captured by hand and measured and weighed. To investigate the food preferences, we adopted a noninvasive method, obtaining faecal samples, which were then analysed under a stereoscopic microscope. A total of 290 faecal samples that could be assigned to individual specimens with determined age and sex were collected. We calculated the relative abundance and occurrence of each prey category. Data were compared by sex and age classes (immatures vs. adults) as a whole and for each of the three sites. A total of 19 prey categories were detected and the number of categories per study site varied between 16 and 18. The most common invertebrates were Araneae and Auchenorrhyncha. Statistically significant differences between immatures and adults were found as adults showed more diverse diet. No such differences between sexes were detected.

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Chronic stressors have profound impacts on phenotypes and life history strategies on the short term, but delayed effects of stress experienced late in life remain poorly investigated in wild populations. Here, we used a combined laboratory and field experiment to test if chronic stress late in life has immediate and delayed effects on physiological and demographic traits in the common lizard, Zootoca vivipara. We increased plasma corticosterone levels in adults and yearlings during three weeks of the post-reproductive season. We quantified immediate responses in the laboratory, delayed intra-generational effects in field enclosures one month and one year later during the next reproductive season, and delayed inter-generational effects in the first generation of offspring. Our phenotypic assays included metabolism, immune capacities, lipid metabolism and oxidative stress. Relative to placebos, lizards treated with corticosterone had higher body condition and lower oxidative damages but an increased skin swelling response directly after the manipulation. Delayed responses in field enclosures were of three types. First, we found catch-up growth for body mass such the placebos had similar body conditions one month after the laboratory manipulation. Second, we found persistent differences in oxidative damages during one month but not one year later. Third, during the next reproductive season, corticosterone-treated females had higher levels of plasma triglycerides, whereas corticosterone-treated individuals had a higher skin swelling response. We found no delayed inter-generational effects on demographic traits of offspring. Our study demonstrates the potential for long-lasting physiological consequences of chronic corticosterone enhancement despite no obvious changes in life history.

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Un dentaire de lézard incomplet, provenant d’une carrière de falun d’Anjou, à Noyant-sous-Lude, Miocène, Orléanien, (MN3) ou MN5 est décrit. Un ensemble de caractères montre qu’il appartient aux Lacertidae ; on citera : la forme arquée de l’ensemble du dentaire, le sulcus Meckeli ouvert jusqu’à la symphyse mandibulaire, la présence de dents faiblement hétérodontes et bicuspides. Cette forme à la dentition banale chez les Lacertidae se distingue facilement des lacertidae à dentition élargie trouvés dans les mêmes niveaux miocènes des faluns. La signification paléoécologique de ces fossiles sera discutée.

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A central theme in ecology and evolution is to understand whether and how species respond to environmental changes. The amount of studies focusing on how species might cope with climate change has been steeply growing, given the importance of the actual climate change. At present, it is widely accepted that changes in mean environmental conditions can affect individual performance, life history strategies and population dynamics. While most climate change scenarios forecast a change in average climatic conditions, they as well predict a decrease in environmental predictability. However, evidence for the effects of environmental predictability is scarce and the few existing studies were mainly theoretical or generated extreme events, which are by themselves negative. Therefore, robust evidence for the predicted negative effects is needed and experiments should test the impact of environmental predictability on life-history traits and population dynamics. For this reason, this doctoral thesis aims at providing robust evidence for the effects of environmental predictability on life-history traits, population dynamics, and species responses. We experimentally tested whether and how changes in the predictability of precipitation affected life history traits and population dynamics of the common lizard Zootoca vivipara, a highly hygrophile species. We simulated more and less predictable precipitation in 12 semi-natural populations. Populations were maintained during one year and the experiment was repeated in two subsequent years. This experimental design allows to understand the generality of the responses and it allows testing whether differences in average climatic conditions may affect differences induced by precipitation predictability. Several parameters were measured to unravel effects of environmental predictability on individual performance and to allow for complex population dynamic models. Decreased environmental predictability, let to reduced growth of yearlings and reduced body condition of female juveniles, but no effects on body condition, growth and survival of adults. This suggests that different age classes and sexes might exhibit different sensitivities to environmental predictability. Less predictable environments negatively affected ornamental coloration of adult males, which shows that less predictable environments are costly. This also suggests that ornamental coloration may act as an early signal of changes in environmental conditions. The results also show that individuals exhibit compensatory strategies to prevent detrimental effects on fitness. The observed differential investment in adult growth, body condition and male ornamental coloration may have allowed to compensate negative effects of decreased precipitation predictability, since no significant differences in reproductive parameters between environmental predictability treatments were found at the end of the experiment. Environmental predictability did not significantly affect the individual key life history traits (i.e. survival and reproduction) and suggesting that compensatory strategies may have prevented major loses in fitness and effects on population dynamics. Nevertheless, the here applied stage-structured matrix model showed that less predictable environments led to a significant decrease of the population growth rate. This suggests that in order to assess the potential effect of climate change on species persistence, complex population dynamics modelling is required. This doctoral thesis is one of the first experimental studies demonstrating whether and how species might respond to changes in environmental predictability. The obtained results underpin predictions from theoretic models, that decreased environmental predictability might negatively affect species responses. Results also suggest that decreased environmental predictability may seriously reduce population persistence and increase species extinction risk. Since species, which are highly susceptible to changes in abiotic conditions, might respond similarly to changes in environmental predictability, the forecasted decrease in environmental predictability might aggravate the actual trends of species decline and extinction. This shows that environmental predictability is a very important non-neglectable determinant of population dynamics, which highlights the necessity to consider its effects in studies forecasting the consequences of climate change.

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The thyroid has been shown to be a target organ of environmental chemicals, specifically endocrine disrupting contaminants. Reptiles are particularly suitable as contaminant biomonitors, due to their persistence in a variety of habitats, wide geographic distribution, longevity, and, in many cases, site fidelity. Nonylphenol, an estrogenic-like compound, can induce vitellogenin synthesis in males and immature reptilian species, but little is known about its effects on thyroid hormones balance. The present study evaluated the potential effects of an acute exposure to nonylphenol (i.p. injected) on the thyroid of the lizard Podarcis sicula. Nonylphenol induced a significant decrease of T4 and T3 plasma levels, in agreement with the decrease of the epithelial cell height; the nuclei of the thyroid cells were small and elongated, with dense chromatin and a greatly reduced cytoplasm. The colloid was retracted with few reabsorption vacuoles. Moreover, nonylphenol administration significantly inhibited plasma thyroid-stimulating hormone levels, thereby altering the thyroid function. This study highlights how the structural and functional disruption of the thyroid gland in non-target organisms as the lizard might also have an environmental aetiology. In conclusion, nonylphenol was suspected to inhibit the thyroid hormones balance, suggesting the thyroid should be included among the other endocrine glands, susceptible to endocrine disruption.

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Background:Hosts and their parasites are under reciprocal selection, leading to coevolution. However, parasites depend not only on a host, but also on the host’s environment. In addition, a single host species is rarely infested by a single species of parasite and often supports multiple species (i.e., multi-infestation). Although the arms race between a parasite and its host has been well studied, few data are available on how environmental conditions may influence the process leading to multiple infestations. In this study, we examine whether: (1) environmental factors including altitude, temperature, vegetation cover, human disturbance, and grazing by livestock affect the prevalence of two types of ectoparasites, mites and ticks, on their host (the common lizard, Zootoca vivipara) and (2) competition is evident between mites and ticks.Results:We found the probability of mite infestation increased with altitude and vegetation cover, but decreased with human disturbance and presence of livestock. In contrast, the probability of tick infestation was inversely associated with the same factors. Individuals with low body condition and males had higher mite loads. However, this pattern was not evident for tick loads. The results from a structural equation model revealed that mites and ticks indirectly and negatively affected each other’s infestation probability through an interaction involving the environ-mental context. We detected a direct negative association between mites and ticks only when considering estimates of parasite load. This suggests that both mites and ticks could attach to the same host, but once they start to accumu-late, only one of them takes advantage.Conclusion:The environment of hosts has a strong effect on infestation probabilities and parasite loads of mites and ticks. Autecological differences between mites and ticks, as indicated by their opposing patterns along environ-mental gradients, may explain the pattern of weak contemporary interspecific competition. Our findings emphasize the importance of including environmental factors and the natural history of each parasite species in studies of host–parasite coevolution.

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A female grass lizard Takydromus stejnegeri van Denburgh was captured after mating in the field on 24 April 2003. It was immediately brought back to the laboratory and kept under observation. It produced four clutches of eggs from10 May to 22 June. The average time interval of the successive clutches was 14.75 days, and the average clutch size was 2.75 eggs. The production of the successive clutches without mating in captivity may be due to the sperm storage in the female reproductive tract. The fertilization ratio and hatching ratio were 100% for the first three clutches, but only 33.3% and none, respectively, for the fourth clutch. The clutch order was significantly positively correlated with egg width and also with egg weight. T. stejnegeri was an intermediate egg retainer, whose gestation (egg retention) period was at an average of 25% of the total embryonic development period.

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The epididymis of the viviparous lizard secretes large amounts of proteins among which L-proteins are prominent components. It undergoes great morphological and physiological modifications during its testosterone-controlled annual cycle. The effects of testosterone on L-proteins synthesis and L-mRNA concentrations were studied in cultures of organs regressed after castration. Of three tested serum supplements (2% Ultroser, 10% fetal calf serum, 10% calf serum) calf serum was shown to be essential for androgen-specific control of L-proteins synthesis. The duration of castration governed the in-vitro response to testosterone principally at the level of L-proteins synthesis. The onset of synthesis was delayed in 2-month post-castration explants, compared with l-month post-castration explants, and was dissociated from appearance of the mRNA. This suggests that there is translational control of secretory proteins in the regressed epididymis. Conversely, the response to testosterone at the mRNA level was delayed in explants from animals castrated during a non-secretory state, compared with explants from animals castrated at the onset of secretion. These results, together with other data, suggest that expression of the L-proteins is under multifactorial control and that the influence of multiple controlling elements varies with the stage of differentiation.

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Complex traits include, among many others, the evolution of eyes, wings, body forms, reproductive modes, human intelligence, social behavior, diseases, and chromosome morphology. Dollo`s law states that the evolution of complex traits is irreversible. However, potential exceptions have been proposed. Here, we investigated whether reticulation, a simple and elegant means by which complex characters may be reacquired, could account for suggested reversals in the evolution of complex characters using two datasets with sufficient genetic coverage and a total of five potential reversals. Our analyses uncovered a potential reversal in the evolution of parity mode and a potential reversal in the evolution of placentotrophy of fish (Cyprinodontiformes) as reticulation events. Moreover, in a reptile that exhibits a potential reversal from viviparity to oviparity (Zootoca vivipara), reticulation provided the most parsimonious explanation for sex chromosome evolution. Therefore, three of the five studied potential reversals were unraveled as reticulation events. This constitutes the first evidence that accounting for reticulation can fundamentally influence the interpretation of the evolution of complex traits, that testing for reticulation is crucial for obtaining robust phylogenies, and that complex ancestral characters may be reacquired through hybridization with a lineage that still exhibits the trait. Hybridization, rather than reappearance of ancestral traits by means of small evolutionary steps, may thus account for suggested exceptions to Dollo`s law. Consequently, ruling out reticulation is required to claim the evolutionary reversal of complex characters and potential exceptions to Dollo`s rule.

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Pastrina Protected Area, a medium-sized Natura 2000 protected area in NW Bulgaria, was chosen as a model site for studying the species diversity of amphibians and reptiles in relation to habitat diversity. The analyses encompass field data for a five-year period. The territory of the survey was divided into a 1 x 1 km grid. The number of species and the number of habitats were recorded for each grid cell. For open and agricultural habitats data were taken from a map with physical blocks. For forested territories, the national forest database was used. The grid cells with missing data were filled in using CORINE Land Cover. A list of threats was prepared in order to estimate their impact. A strong correlation between habitat and species diversity was found: the latter was clearly determined by the presence of certain habitats known to maintain high species diversity. Habitats such as the thermophilous deciduous forests and their surrounding territories were the most important habitats, with higher species diversity and a higher percentage of species of conservation priority, e.g. Triturus cristatus, Bombina bombina, B. variegata and Testudo hermanni. These species were found from only 11.7% of the territory of the protected area, that makes those species vulnerable, with an uncertain future status.