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Animal signals are dynamic traits that can undergo considerable spatial and temporal changes and that are influenced by factors such as age, health condition and interactions with both the abiotic and biotic environment. However, much of our understanding of signal changes throughout an individual's lifetime stems from cross‐sectional, often laboratory‐based, studies focused on visual and auditory signals. Longitudinal field investigations of temporal variation in chemical signals, especially in vertebrates, remain rare despite chemical communication being the most ubiquitous form of information exchange in the natural world. To remedy this, we conducted a unique, replicated field experiment to study the temporal signal dynamics in free‐living lizard populations on natural islands. Specifically, we collected scent marks from individually marked lizards across five populations during the spring of two consecutive years and analysed the lipophilic chemical composition of these scent marks. Our findings demonstrate that the overall scent mark composition of individual lizards changed over time, shifting consistently in both direction and magnitude from year to year among individuals and across replicate populations. Similar patterns were observed for the chemical richness and diversity of scent marks. Temporal variation in the relative proportions of three potentially socially relevant signalling compounds in lizard scent marks revealed a more complex pattern: α‐tocopherol remained stable over time, oleic acid decreased and the change in octadecanoic acid proportion was body size‐dependent. Together, our results provide novel insights into how individual vertebrate chemical signals may fluctuate across space and time. We discuss the potential causes of the observed temporal variability and its consequences for chemical signal evolution. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Marine iguanas (Amblyrhynchus cristaus) are indigenous to the Galápagos Islands, a group of islands in the Pacific Ocean formed by volcanoes. Materials you will need: A computer or device with internet access Students will be involved in cutting-edge research on marine iguanas and their habitat while engaged in Iguanas from Above. Is a citizen science project designed to answer questions about marine iguanas, their population, and their habitat. [Extracted from the article]

Background: Environmental conditions on Earth are repeated in non-random patterns that often coincide with species from different regions and time periods having consistent combinations of morphological, physiological and behavioral traits. Observation of repeated trait combinations among species confronting similar environmental conditions suggest that adaptive trait combinations are constrained by functional tradeoffs within or across niche dimensions. In an earlier study, we assembled a high-resolution database of functional traits for 134 lizard species to explore ecological diversification in relation to five fundamental niche dimensions. Here we expand and further examine multivariate relationships in that dataset to assess the relative influence of niche dimensions on the distribution of species in 6-dimensional niche space and how these may deviate from distributions generated from null models. We then analyzed a dataset with lower functional-trait resolution for 1023 lizard species that was compiled from our dataset and a published database, representing most of the extant families and environmental conditions occupied by lizards globally. Ordinations from multivariate analysis were compared with null models to assess how ecological and historical factors have resulted in the conservation, divergence or convergence of lizard niches. Results: Lizard species clustered within a functional niche volume influenced mostly by functional traits associated with diet, activity, and habitat/substrate. Consistent patterns of trait combinations within and among niche dimensions yielded 24 functional groups that occupied a total niche space significantly smaller than plausible spaces projected by null models. Null model tests indicated that several functional groups are strongly constrained by phylogeny, such as nocturnality in the Gekkota and the secondarily acquired sit-and-wait foraging strategy in Iguania. Most of the widely distributed and species-rich families contained multiple functional groups thereby contributing to high incidence of niche convergence. Conclusions: Comparison of empirical patterns with those generated by null models suggests that ecological filters promote limited sets of trait combinations, especially where similar conditions occur, reflecting both niche convergence and conservatism. Widespread patterns of niche convergence following ancestral niche diversification support the idea that lizard niches are defined by trait-function relationships and interactions with environment that are, to some degree, predictable and independent of phylogeny. [ABSTRACT FROM AUTHOR]

Given the rapid loss of biodiversity as consequence of climate change, greater knowledge of ecophysiological and natural history traits are crucial to determine which environmental factors induce stress and drive the decline of threatened species. Liolaemus montanezi (Liolaemidae), a xeric-adapted lizard occurring only in a small geographic range in west-central Argentina, constitutes an excellent model for studies on the threats of climate change on such microendemic species. We describe field data on activity patterns, use of microhabitat, behavioral thermoregulation, and physiology to produce species distribution models (SDMs) based on climate and ecophysiological data. Liolaemus montanezi inhabits a thermally harsh environment which remarkably impacts their activity and thermoregulation. The species shows a daily bimodal pattern of activity and mostly occupies shaded microenvironments. Although the individuals thermoregulate at body temperatures below their thermal preference they avoid high-temperature microenvironments probably to avoid overheating. The population currently persists because of the important role of the habitat physiognomy and not because of niche tracking, seemingly prevented by major rivers that form boundaries of their geographic range. We found evidence of habitat opportunities in the current range and adjacent areas that will likely remain suitable to the year 2070, reinforcing the relevance of the river floodplain for the species' avoidance of extinction. [ABSTRACT FROM AUTHOR]

Ecological studies strive to identify factors that explain patterns of species distribution and abundance. In lizards, competition and predation are major forces influencing distribution and abundance, but there is also increasing evidence pointing at the influence of habitat structure and prey abundance. Our work explored the latter further by quantifying the effects of vegetation and prey abundance on occupancy and abundance (i.e., estimated probability of detecting more than two individuals) of two sympatrically occurring species in the northern karst belt of Puerto Rico. We hypothesized that Anolis cristatellus would occur in trunk–ground substrates and Anolis krugi on grass–bush substrates according to their ecomorphological classification. We also hypothesized that prey abundance, a component of habitat quality, would have a positive and strong effect on occupancy and abundance. Anolis cristatellus exhibited high occupancy rates (>0.80), influenced by mid-story tree size. A. cristatellus abundance fluctuated over time, with highest probability of detecting two or more individuals in January–March and July–September when prey abundance transitioned from low to high levels. Occupancy of A. krugi was positively influenced by sapling density and prey abundance. Prey abundance exerted a stronger influence on occupancy, but its influence on abundance was negative and strong. Biological interactions and the type of understory substrates may explain the negative relationship. Our study supported predicted relationships between ecomorphology and habitat, but also showed that higher prey abundance may not always translate to higher local abundance. We shed light on these interactions, knowledge needed to advance anole conservation in the advent of land use and climate change. [ABSTRACT FROM AUTHOR]

Anolis lizards are common throughout the islands of the West Indies, often with several species existing in sympatry by demonstrating conspicuous niche separation. With increasing occurrences of Anolis species being introduced to islands outside of their natural range, there is potential for significant disturbance to natural Anolis communities and particularly to endemic species that have evolved in the absence of congeners. Here we report on the status of non-native Anolis lizards now present on the island of Saint Lucia, historically a single species island, and discuss the potential impact these introductions may have on endemic Anolis luciae. Through systematic visual encounter surveys and opportunistic sightings we present evidence for the widespread dispersal of Watts' anole (A. wattsi), indications of range expansion of Barbados anole (A. extremus), and the arrival and dispersal of a third species, the Cuban brown anole (A. sagrei). Our data suggest the presence of at least two of these species may be having a detrimental impact on the abundance of A. luciae, particularly in disturbed habitats. [ABSTRACT FROM AUTHOR]

Only 2 lizard species of the 11 members of the genus Loxopholis Cope, 1869 are found in Central America, L. southi (Ruthven & Gaige, 1924) from Costa Rica to Colombia and L. rugiceps Cope, 1869 from Panama and Colombia. We report new country records for L. rugiceps from Honduras and Costa Rica. We collected 4 individuals of this species in Honduras in 2018 and 2 specimens in Costa Rica in 1997 and 2017. We discuss the distribution of L. rugiceps in Central America. [ABSTRACT FROM AUTHOR]

In an increasingly urbanized world it is imperative that we understand how wildlife responds to this novel anthropogenic landscape, both at the individual‐ and population‐level. Urbanization generally reduces biodiversity, but can also favour particular species and increase their abundance relative to wild populations. When population density increases, so too does the frequency and cost of social interactions. We studied Australian water dragons (Intellagama lesueurii), a species common in urban, semi‐natural and natural areas, to firstly test the prediction that urban populations occur at higher densities, and then determine the consequences of urbanization for combat rates (quantified using wounding) and bite force. We established that urban populations are denser than ones from semi‐natural and natural habitats. We also recorded significantly more wounds in females from urban populations than females from both natural and semi‐natural populations. Urban males also had significantly higher incidence of wounding than males from natural populations. We did not find a difference in male or female bite force among any populations across the urban‐natural gradient. Overall, we found evidence that urbanization results in a higher population density of water dragons and more frequent conspecific combat, but this was not associated with an increase in bite force. These finding suggests that there may be a physiological cost to living in urban habitats related to increased contest rates and wounding. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Mitochondrial and nuclear genetic data indicate strong phylogeographic structure. • Results consistent with biogeographic barriers at the Nullarbor Plain and Murray River. • Molecular clock analyses suggest diversification occurred in the Plio-Pleistocene. • Analyses indicate presence of one or more refugia associated with each of the three main populations. Abstract Palaeoclimatic events and biogeographical processes since the mid-Tertiary have played an important role in shaping the evolution and distribution of Australian fauna. However, their impacts on fauna in southern and arid zone regions of Australia are not well understood. Here we investigate the phylogeography of an Australian scincid lizard, Tiliqua rugosa , across southern Australia using mitochondrial DNA (mtDNA) and 11 nuclear DNA markers (nuDNA), including nine anonymous nuclear loci. Phylogenetic analyses revealed three major mtDNA lineages within T. rugosa , geographically localised north and south of the Murray River in southern Australia, and west of the Nullarbor Plain. Molecular variance and population analyses of both mtDNA and nuDNA haplotypes revealed significant variation among the three populations, although potential introgression of nuDNA markers was also detected for the Northern and Southern population. Coalescent times for major mtDNA lineages coincide with an aridification phase, which commenced after the early Pliocene and increased in intensity during the Late Pliocene-Pleistocene. Species distribution modelling and a phylogeographic diffusion model suggest that the range of T. rugosa may have contracted during the Last Glacial Maximum and the locations of optimal habitat appear to coincide with the geographic origin of several distinct mtDNA lineages. Overall, our analyses suggest that Plio-Pleistocene climatic changes and biogeographic barriers associated with the Nullarbor Plain and Murray River have played a key role in shaping the present-day distribution of genetic diversity in T. rugosa and many additional ground-dwelling animals distributed across southern Australia. [ABSTRACT FROM AUTHOR]

The common wall lizard has been widely introduced across Europe and overseas. We investigated the origin of putatively introduced Podarcis muralis populations from two southern Europe localities: (i) Ljubljana (Slovenia), where uncommon phenotypes were observed near the railway tracks and (ii) the port of Vigo (Spain), where the species was recently found 150 km far from its previously known range. We compared cytochrome-b mtDNA sequences of lizards from these populations with published sequences across the native range. Our results support the allochthonous status and multiple, long-distance origins in both populations. In Ljubljana, results support two different origins, Serbia and Italy. In Vigo, at least two separate origins are inferred, from western and eastern France. Such results confirm that human-mediated transport is promoting biological invasion and lineage admixture in this species. Solid knowledge of the origin and invasion pathways, as well as population monitoring, is crucial for management strategies to be successful. [ABSTRACT FROM AUTHOR]

Various factors may alter anti-predatory responses among conspecifics. Here we assess some of these factors using three populations of a Mediterranean lizard (Acanthodactylus schreiberi) in Cyprus that differ in their habitat type, predator diversity and population density. We expected that predation would affect flight initiation distance (FID; the approach distance allowed to an observer before the lizard flees), escape distance (ED; the distance covered by the lizard from the point an escape attempt starts to the first place the lizard stops) and tail autotomy (autotomy rates, economy of autotomy, post-autotomy tail movement). We also predicted that juveniles, being more exposed to predators, would be more effective in their defensive responses. Our findings suggest that predation and population density appear to be associated with most autotomy traits but were not associated with FID and ED, which are better explained by refuge availability. The only ontogenetic difference was detected in the economy of autotomy: juveniles are more prone to autotomise, possibly because they do not experience such high costs as tailless adult individuals. Our results suggest that anti-predatory responses are influenced by a variety of factors. Unravelling the compound effects of all the factors involved should be the focus of future research. [ABSTRACT FROM AUTHOR]

Detailed investigations of ecology and life history of lizards in New Zealand/Aotearoa are needed to inform their conservation and management. An early demographic study of copper skinks (Oligosoma aeneum) in a suburban garden was undertaken in Lower Hutt using mark-recapture methods, sampling weekly from March 1971 to December 1973. Oligosoma aeneum were seen on 1372 occasions, with 972 captures of 169 individuals. The maximum snout-vent length was 66 mm, 33% of skinks had complete tails, and colour differences suggested sexual signalling and warrant further study. Most captures occurred over November-March, with fewest over June-August. The estimated spring/summer population size in the garden (± SEM) was 83.6 (± 9.4) skinks, and the annual survival rate (± SEM) was 38.0% (± 16.0%). This is one of the few New Zealand lizard studies that have extended through all months of the year and it adds to limited information on lizard populations in suburban areas. [ABSTRACT FROM AUTHOR]

Nesting in tropical highlands is challenging due to the fluctuations of temperature, including extreme cold, and humidity. For most reptiles in the highland tropical region the thermal and hydrological profiles of nests have not been described, and it is therefore uncertain how future climate change may affect this ontogenetic stage. We monitored 17 communal nests of Anadia bogotensis at a highland locality in Colombia. The soil humidity and temperature of the nests and the air temperature were recorded for almost a year, together with other physical and biotic nest characteristics. Nests exhibited high temporal and spatial thermal variation unrelated to the nests' physical characteristics. The maximum and minimum temperatures of the nests and air exhibited a linear and positive relationship, whereas the thermal variance (CV) exhibited a linear and positive relationship with maximum air temperature. Furthermore, CV of the heating phase was higher than that of the cooling phase for the nest and air temperature and it was similar between nests with and without viable eggs. However, it was different between each nest type and air temperature. During the cooling phase the average CV was different between nests with and without viable eggs and between nests and air temperature. In conclusion, the temperature of the nests exhibits strong daily fluctuation, and most of the nests follow the same fluctuation as air temperature. However, it seems that the rock covering some nests prevents the nest temperature from falling as quickly as the air temperature and from reaching the minimum environmental value. [ABSTRACT FROM AUTHOR]

Simiscincus aurantiacus was described in 1997 from a single specimen collected in humid forest habitat on Mt Koghis in southern New Caledonia. The recent acquisition of a number of additional specimens from surveys conducted in the south of the island has provided new information on the species' morphology, biology and distribution. The results of field studies indicate it has a scattered distribution across the region that includes both humid forest and tall, canopied maquis forest habitats, and that it can persist in even extremely small remnants of these forest types and appears to have a primarily subterranean mode of existence. The additional material collected has also allowed an assessment of variation in the species' morphology, including an unusually long tail the basal half of which is uniformly rounded. Morphological studies suggest a close relationship between Simiscincus aurantiacus and the regionally sympatric fossorial species Graciliscincus shonae, and genetic studies undertaken since its description place these taxa within a larger group that also includes the surface active species of the genera Caledoniscincus and Phaeoscincus, the latter only recently established. The information on the species' distribution and biology presented here supports its recent IUCN Red List assessment as Vulnerable. [ABSTRACT FROM AUTHOR]

Abstract: Accelerated climate change represents a major threat to the health of the planet's biodiversity. Particularly, lizards of the genus Xenosaurus might be negatively affected by this phenomenon because several of its species have restricted distributions, low vagility, and preference for low temperatures. No study, however, has examined the climatic niche of the species of this genus and how their distribution might be influenced by different climate change scenarios. In this project, we used a maximum entropy approach to model the climatic niche of 10 species of the genus Xenosaurus under present and future suitable habitat, considering a climatic niche conservatism context. Therefore, we performed a similarity analysis of the climatic niche between each species of the genus Xenosaurus. Our results suggest that a substantial decrease in suitable habitat for all species will occur by 2070. Among the most affected species, X. tzacualtipantecus will not have suitable conditions according to its climatic niche requirements and X. phalaroanthereon will lose 85.75% of its current suitable area. On the other hand, we found low values of conservatism of the climatic niche among species. Given the limited capacity of dispersion and the habitat specificity of these lizards, it seems unlikely that fast changes would occur in the distribution of these species facing climate change. The low conservatism in climatic niche we found in Xenosaurus suggests that these species might have the capacity to adapt to the new environmental conditions originated by climate change. [ABSTRACT FROM AUTHOR]

Abstract: Most oviparous squamate reptiles lay their eggs when embryos have completed less than one‐third of development, with the remaining two‐thirds spent in an external nest. Even when females facultatively retain eggs in dry or cold conditions, such retention generally causes only a minor (<10%) decrease in subsequent incubation periods. In contrast, we found that female sand lizards (Lacerta agilis) from an experimentally founded field population (established ca. 20 years ago on the southwest coast of Sweden) exhibited wide variation in incubation periods even when the eggs were kept at standard (25°C) conditions. Females that retained eggs in utero for longer based on the delay between capture and oviposition produced eggs that hatched sooner. In the extreme case, eggs hatched after only 55% of the “normal” incubation period. Although the proximate mechanisms underlying this flexibility remain unclear, our results from this first full field season at the new study site show that females within a single cold‐climate population of lizards can span a substantial proportion of the continuum from “normal” oviparity to viviparity. [ABSTRACT FROM AUTHOR]

Starting in 2012, and peaking in 2013, drought conditions in the Great Basin Desert persisted for almost four years. By studying a meta-population of Common Side-blotched Lizards in the wild, we found that a failure of spring rains correlated with a marked reduction of body condition in female, but not male, lizards. Likewise, rainfall correlated with reproductive scores of females such that a failure of spring rains in 2013 resulted in a cessation of the breeding season. By 2014 it was apparent that the drought had caused a general failure of recruitment into the population, which affected the body-size distribution of lizards for several subsequent years. To disentangle the effects of both water and food availability during a drought, we next conducted a laboratory experiment by imposing a drought on breeding animals, but not otherwise limiting food. Results indicate that the absence of drinking water alone tends to delay the breeding season as well as cause reproductive failure in females even as body condition was maintained. Our combination of field and laboratory data reveal that body condition and reproductive responses to drought are not strictly about food limitations, but are also caused by a lack of available drinking water. [ABSTRACT FROM AUTHOR]

Temperature is one of the main environmental variables shaping the evolution and biology of terrestrial ectotherms. The Pantanal is the largest continuous wetland in the World. However, a lack of knowlegde still exists on the thermal ecology of terrestrial ectothems from this wetland. In this context, the thermal ecology of the lizard Tropidurus lagunablanca Carvalho, 2016 (Squamata, Tropiduridae) was investigated in the Brazilian Pantanal. The thermal ecology and microhabitat use of lizards from a riparian forest was compared to lizards from a park savanna. At both studied areas, air and body temperatures of lizards did not differ between sexes. Mean T. lagunablanca body temperatures were higher at the savanna compared to the forest, while air temperatures were similar in both habitats. The main substrates were tree trunks, with a frequency of approximately 90% of the observations. Lizards from the savanna used higher perches than those from the forest despite -in average- trees were higher at the forest. Lizard sun and shade exposure was similar for both areas. Lizards from both habitats showed similar strong linear relationships between body and air temperatures. However, lizard behaviour of using tree trunk perches differently under different sunlight situations suggests that these lizards actively thermoregulate. Further research on the thermoregulation abilities of this species, with a null hypotesis and behavioral observations will shed light on lizard thermal biology. Studies on the ecophysiological aspects of these lizards should be a priority to understand how they will react to climate change and which conservation measures will be more effective concerning their preservation. [ABSTRACT FROM AUTHOR]

Regeneration of secondary forests on previously deforested or degraded land is one of the most dominant forms of land-use change in the tropics. However, the response of animal communities to forest regeneration is poorly understood. To evaluate support for thermal quality as a mechanism driving reptile species distributions during secondary forest succession, we measured operative temperatures and occupancy in three successional forest stages (pasture, secondary forest, and old growth forest) for two anole species common in the landscape ( Norops humilis and Norops limifrons ). We then measured thermal preference in laboratory experiments and used operative temperature and temperature preference measurements to determine how thermal quality of habitat changes over the course of secondary forest succession, and if occupancy varies as a function of thermal quality. We found that thermal quality was lowest in pasture habitat because of a large frequency of temperatures above the thermal preference range. However, in low thermal quality pasture sites, riparian habitats and remnant trees provided a thermal refuge for both lizard species. Our results support thermal quality as a mechanism for reptile species distributions in altered landscapes and highlight the importance of the maintenance of riparian corridors. [ABSTRACT FROM AUTHOR]

Activity patterns in ectotherms rely on the structure of the thermal environment and thermoregulatory opportunities during activity periods. A dichotomy between diurnal and nocturnal ectotherms is not clear in every case, and temperature can directly affect the daily activity period in these organisms during both photophase and scotophase. In the present study we evaluate the thermal ecology of six tropical night lizards (genus Lepidophyma ) from Mexico. Our results indicate a thermoconformer strategy in most of the studied species. In these species, thermal tolerances are associated with environmental temperatures to which they are exposed. Furthermore, thermal quality of the environment directly determines the daily activity period. Therefore, we argue that diurnal activity in Lepidophyma species is determined by local thermal conditions. [ABSTRACT FROM AUTHOR]

Fire is a critical component of terrestrial ecosystems and essential to understand the composition and diversity of communities in fire-prone regions. Nevertheless, fire does not act alone, and other factors such as land-use type and vegetation structure can also operate at different scales, prompting the response to fire of ectotherm communities such as reptiles. We have evaluated the influence of environmental factors on the abundance, diversity, and richness of reptile communities in Serra da Estrela Natural Park (northern Portugal), at both the landscape and micro-habitat scales. In spring 2014 and 2015, 20 transects were surveyed eight times, the vegetation structure and composition were measured, and the extent of land-use types around each transect calculated in this Mediterranean community. At the landscape scale, reptile abundance was higher in natural woodlands and more complex habitats (higher vegetation heterogeneity and plant richness), and reptile evenness was affected by vegetation heterogeneity and time since fire. By contrast, species richness was not related to any environmental factor measured in this study. Only two lizard species were common in the park, Psammodromus algirus and Podarcis guadarramae . Their relative abundances increased with contrasting habitat variables as the former is a ground-dwelling lizard specialist that prefers heterogeneous (unburnt) habitats and the second is a rock lizard that selects open (burnt) stands. At the micro-habitat scale, the probability of reptile presence, reptile abundance, and reptile richness increased with plant richness and decreased with tree cover. This study highlights the importance of several environmental factors, that operate from micro-habitat to landscape scales to understand the response of reptiles to fire. [ABSTRACT FROM AUTHOR]

We describe two new species of Anolis lizard that are sympatric on the Amazonian slopes of the Andes of southern Ecuador at elevations between 1440 and 1970 m. The new species may be distinguished from other Anolis by external anatomy, mitochondrial divergence and dewlap colour. We estimate the phylogenetic positions of the new species using Bayesian analysis of DNA sequence data including all species of Dactyloa-clade Anolis for which DNA data are available. Anolis hyacintogularis sp. nov. is sister to Anolis calimae, whereas Anolis lososi sp. nov. is sister to Anolis williamsmittermeierorum, herein reported for Ecuador for the first time. Individuals of both new species were collected within a protected area in southern Ecuador, Podocarpus National Park, which suggests that at least some populations of these species are well protected. www.zoobank.org/urn:lsid:zoobank.org:pub:E55FA804-E3FD-4412-8FEB-5234E29E272D [ABSTRACT FROM AUTHOR]

Ecology has long sought whether there are general assembly rules that underlie patterns of community organization. However, new perspectives of community disassembly and reassembly have emerged as environments depart from baseline conditions due to agents of global change. A trait-based approach can provide insights as to how changes affect performance of a species and their subsequent loss, gain, or persistence in an assemblage. We quantified the spatiotemporal dynamics in species and functional diversity from systematic surveys of local lizard assemblages distributed along an elevation gradient from three surveys in a 50-year period (1950s–2000s) in Big Bend National Park (BBNP), USA. BBNP was subjected to and then released from intensive grazing, which has resulted in changes to vegetative composition and cover. We examine changes in local assemblages in the context lizard functional traits, including thermal niche breadth. We hypothesized that temperature specialists were more likely to colonize or be lost from local sites. Species richness was lowest in the 1950s (N = 3 species), and subsequent surveys revealed that species richness increased in both the 1960s and 2000s (N = 6 and N = 8 species, respectively), but not all sites responded uniformly. We found that functional diversity in this system was not affected by this drastic increase species richness, indicative of functional redundancy in species traits. Lizards that were added to sites tended to be smaller bodied with lower thermal tolerances. Lizards with high preferred body temperatures were locally extirpated from high elevation sites that experienced high shrub encroachment, likely due to a reduction in the preferred thermal gradients these species. These results reveal that long-term desert lizard functional diversity was maintained, but the consequences of changes to functional diversity at the local scale need to be examined further. [ABSTRACT FROM AUTHOR]

Understanding the climatic and historical factors shaping species richness is a major goal of ecology and biogeography. Consensus on how climate affects species richness is still lacking, but four potential and non-exclusive explanations have emerged: water–energy, where diversity is determined by precipitation and/or temperature; seasonality, where diversity is determined by seasonal variation in climate; heterogeneity, where diversity is determined by spatial variability in climate; and historical climatic stability, where diversity is determined by changes in climate through evolutionary time. Climate–richness relationships are also mediated by historical processes, such as phylogenetic niche conservatism and lineage diversification across regions. We evaluated the effect of climate on species richness gradients of Anolis lizards and tested the role of phylogenetic niche conservatism and regional diversification in the origin and maintenance of climate–richness relationships. Climate had a strong nonstationary relationship with species richness, with strong shared effects among several climate axes. Regional differences in climate–richness relationships suggest different assembly processes between regions. However, we did not find evidence for a role of evolutionary factors, such as phylogenetic niche conservatism or regional diversification, underlying these relationships. We suggest that evolutionary processes affecting climate–richness relationships in Anolis were probably obscured by high dispersal rates between regions. [ABSTRACT FROM AUTHOR]

Caribbean Anolis lizards exhibit a complex suite of ecological, morphological, and behavioral traits that allow their specialization to particular microhabitats. These microhabitat specialists, called ecomorphs, have independently evolved on the four islands of the Greater Antilles, and diversification among anole ecomorphs has been the focus of many studies. Yet, habitat specialization has also occurred among species within the same ecomorph group. Here, we examined ecological, morphological, and behavioral divergence in three Hispaniolan trunk-ground species, the cybotoid anoles: Anolis cybotes, A. marcanoi, and A. longitibialis. We found differences in limb morphology, locomotor behavior, and perch use among the three cybotoid species that mirror differences across the ecomorphs. Among these species of cybotoids, those that have longer limbs tend to move less frequently, occupy broader perches, and have smaller fourth toes with fewer lamellae. We also observed that the species with greater male-biased size dimorphism had larger heads, smaller dewlaps, and smaller testes. These results are consistent with the predictions of sexual selection theory, in that species with large male body size may have larger heads because of increased male-male combat, and smaller testes potentially attributable to a trade-off between pre- and postcopulatory selection. Overall, our study suggests that a combination of local adaptation to different structural habitats and sexual selection might produce ecomorphological diversification within cybotoid anoles of the same ecomorph group. [ABSTRACT FROM AUTHOR]

We describe a new species of Tupinambis from central South America in a transitional region between Amazonia, Cerrado, and Pantanal. The new species differs from its congeners by the number of femoral pores, posterior gulars, and mesoptychial scales and by color pattern. It is partially sympatric with Tupinambis cuzcoensis, Tupinambis longilineus, Tupinambis quadrilineatus, and maybe also with Tupinambis teguixin, but in general terms they tend to substitute one another in space. [ABSTRACT FROM AUTHOR]

A new species of Leposternon is described from the Brazilian Cerrado, with records from the municipalities of Buritizeiro and João Pinheiro, state of Minas Gerais, central Brasil. The new species has precloacal pores and pectorals scales mostly diamond shaped, and these characteristics distinguish it from all congeners except Leposternon cerradensis, Leposternon kisteumacheri, Leposternon maximus, and Leposternon polystegum. It differs from the pored Leposternon species by a combination of external morphology and dental features. The morphology of the new species is similar to other species of the genus Leposternon with precloacal pores. [ABSTRACT FROM AUTHOR]

Several Caucasian rock lizards of the genus Darevskia of hybrid origin are known to reproduce parthenogenetically. Local communities can be composed exclusively of parthenogens, though syntopy with bisexual members of the genus may occur. In some localities, reproduction between bisexual and parthenogenetic Darevskia has been previously reported based on lizard intermediate morphology and karyology (3n, 4n). However, the frequency of such heterospecific matings remains unknown. We indirectly quantified the reproductive interactions through the inspection of copulation marks in females in a mixed Darevskia community from Kuchak (Armenia) composed of two hybrid parthenogens (D. armeniaca and D. unisexualis), one bisexual species (D. valentini) and their putative backcrosses. A total of 139 adults were randomly collected and photographed. Females were later measured (SVL), inspected for inguinal marks and ranked from 0 (no scars) to 3 (= 3 scars). The lizard species and ploidy determination was ensured by a parallel microsatellite analysis. Sex-ratio in the community was extremely biased due to the high abundance of parthenogenetic females. All female types displayed copulation marks with frequencies varying from 80% in D. valentini to 64% in D. armeniaca. Remarkably, 7 out of 11 (64%) backcross females also showed marks. In the most abundant D. armeniaca, the prevalence and intensity of copulation marks increased with body size, just as predicted for polygynous female lacertids. These results indicate that copulation between parthenogenetic and bisexual species in Darevskia mixed communities is common and driven by sexual selection, thus reinforcing previous suggestions of reproductive interaction in syntopy. Evolutionary implications of these findings are discussed. [ABSTRACT FROM AUTHOR]

Abstract: The signals that animals use to communicate often differ considerably among species. Part of this variation in signal design may derive from differential natural selection on signal efficacy; the ability of the signal to travel efficiently through the environment and attract the receiver's attention. For the visual and acoustic modalities, the effect of the physical environment on signal efficacy is a well‐studied selective force. Still, very little is known on its impact on chemical signals. Here, we took a broad, phylogenetic comparative approach to test for a relationship between animals' signal chemistry and properties of their natural environment. Our study focused on lizards from the Lacertidae family. We sampled 64 species across three continents and determined the lipophilic composition of their glandular signalling secretions using gas chromatography–mass spectrometry. For each species, an array of environmental variables of high temporal and spatial resolution was obtained from climate databases. Species varied considerably in the overall richness (number of constituents) of their secretions, as well as in the relative contribution of the major chemical compound classes. Signal richness and the relative contribution of the respective compounds exhibited little evidence of phylogenetic relatedness, suggesting that chemical signals may change very rapidly. Neither insularity nor substrate use affected chemical signal composition, however, we found a strong statistical relationship between the chemistry of the lizards' secretions and aspects of the thermal and hydric environment they inhabit. Species from ‘xeric’ milieus contained high proportions of stable fatty acid esters and high molecular weight alcohols in their glandular secretions, which likely increase the persistence of secretion scent‐marks. In contrast, species inhabiting ‘mesic’ environments produced secretions of a high chemical richness comprising high levels of aldehydes and low molecular weight alcohols. This chemical mix probably creates a volatile‐rich signal that can be used for long‐distance airborne communication. We argue that the observed variation in signal design results from differential natural selection, optimizing signal efficacy under contrasting environmental conditions. A plain language summary is available for this article. [ABSTRACT FROM AUTHOR]

Abstract: The performance of ectotherms integrated over time depends in part on the position and shape of the distribution of body temperatures (Tb) experienced during activity. For several complementary reasons, physiological ecologists have long expected that Tb distributions during activity should have a long left tail (left‐skewed), but only infrequently have they quantified the magnitude and direction of Tb skewness in nature. To evaluate whether left‐skewed Tb distributions are general for diurnal desert lizards, we compiled and analysed Tb (∑ = 9,023 temperatures) from our own prior studies of active desert lizards in three continents (25 species in Western Australia, 10 in the Kalahari Desert of Africa and 10 species in western North America). We gathered these data over several decades, using standardized techniques. Many species showed significantly left‐skewed Tb distributions, even when records were restricted to summer months. However, magnitudes of skewness were always small, such that mean Tb were never more than 1°C lower than median Tb. The significance of Tb skewness was sensitive to sample size, and power tests reinforced this sensitivity. The magnitude of skewness was not obviously related to phylogeny, desert, body size or median body temperature. Moreover, a formal phylogenetic analysis is inappropriate because geography and phylogeny are confounded (i.e. are highly collinear). Skewness might be limited if lizards pre‐warm inside retreats before emerging in the morning, emerge only when operative temperatures are high enough to speed warming to activity Tb, or if cold lizards are especially wary and difficult to spot or catch. Telemetry studies may help evaluate these possibilities. A plain language summary is available for this article. [ABSTRACT FROM AUTHOR]

Squamate embryos require weeks of high temperature to complete development, with the result that cool climatic areas are dominated by viviparous taxa (in which gravid females can sun-bask to keep embryos warm) rather than oviparous taxa (which rely on warm soil to incubate their eggs). How, then, can some oviparous taxa reproduce successfully in cool climates - especially late in summer, when soil temperatures are falling? Near the northern limit of their distribution (in Sweden), sand lizards ( Lacerta agilis) shift tactics seasonally, such that the eggs in late clutches complete development more quickly (when incubated at a standard temperature) than do those of early clutches. That acceleration is achieved by a reduction in egg size and by an increase in the duration of uterine retention of eggs (especially, after cool weather). Our results clarify the ability of oviparous reptiles to reproduce successfully in cool climates and suggest a novel advantage to reptilian viviparity in such conditions: by maintaining high body temperatures, viviparous females may escape the need to reduce offspring size in late-season litters. [ABSTRACT FROM AUTHOR]

Background: The development of male- or female-specific phenotypes in squamates is typically controlled by either temperature-dependent sex determination (TSD) or chromosome-based genetic sex determination (GSD). However, while sex determination is a major switch in individual phenotypic development, it is unknownhow evolutionary tran- sitions between GSD and TSD might impact on the evolution of squamate phenotypes, particularly the fast-evolving and diverse genitalia. Here, we take the unique opportunity of studying the impact of both sex determination mecha- nisms on the embryological development of the central bearded dragon ( Pogona vitticeps ). This is possible because of the transitional sex determination system of this species, in which genetically male individuals reverse sex at high incubation temperatures. This can trigger the evolutionary transition of GSD to TSD in a single generation, making P. vitticeps an ideal model organism for comparing the effects of both sex determination processes in the same species. Results: We conducted four incubation experiments on 265 P. vitticeps eggs, covering two temperature regimes (“normal" at 28 °C and “sex reversing" at 36 °C) and the two maternal sexual genotypes (concordant ZW females or sex-reversed ZZ females). From this, we provide the first detailed staging system for the species, with a focus on genital and limb development. This was augmented by a new sex chromosome identification methodology for P. vit- ticeps that is non-destructive to the embryo. We found a strong correlation between embryo age and embryo stage. Aside from faster growth in 36 °C treatments, body and external genital development was entirely unperturbed by temperature, sex reversal or maternal sexual genotype. Unexpectedly, all females developed hemipenes (the genital phenotype of adult male P. vitticeps ), which regress close to hatching. Conclusions: The tight correlation between embryo age and embryo stage allows the precise targeting of specific developmental periods in the emerging field of molecular research on P. vitticeps . The stability of genital development in all treatments suggests that the two sex-determining mechanisms have little impact on genital evolution, despite their known role in triggering genital development. Hemipenis retention in developing female P. vitticeps , together with frequent occurrences of hemipenis-like structures during development in other squamate species, raises the possibility of a bias towards hemipenis formation in the ancestral developmental programme for squamate genitalia. [ABSTRACT FROM AUTHOR]

Rotational logging practices are used with the goal of reducing forest disturbance impacts on biodiversity. However, it is poorly understood whether such forest management practices conserve the demographic and genetic composition of animal populations across logged landscapes. Here we investigated whether rotational logging practices alter patterns of landscape-scale population abundance and genetic diversity of a forest-dwelling lizard (Eulamprus heatwolei) in south-eastern Australia. We sampled lizards (n = 407) at up to 48 sites across a chronosequence of logging disturbance intervals (<10 to >60 years after logging) to assess site-specific population changes and genetic diversity parameters. Lizard abundances exhibited a significant curvilinear response to time since logging, with decreased numbers following logging (<10 years), increased abundance as the forest regenerated (10-20 years), before decreasing again in older regenerated forest sites (>30 years). Lizard genetic diversity parameters were not significantly influenced by logging disturbance. These results suggest that logging practices, whilst inducing short-term changes to population abundance, had no measurable effects on the landscape-scale genetic diversity of E. heatwolei. These results are important as they demonstrate the value of monitoring for evaluating forest management efficacy, and the use of different population-level markers to make stronger inference about the potential impacts of logging activities. [ABSTRACT FROM AUTHOR]

Aim To infer the biogeographical and evolutionary history of the Western Mediterranean Psammodromus lizards with the aim of assessing the role of vicariance and dispersal on the cladogenetic events within the palaeogeological dynamics of the Strait of Gibraltar. Location North Africa and Western Europe. Methods We built a dataset including all six species of Psammodromus using mitochondrial ( 12S, cytb, nd4) and nuclear ( acm4, mc1r, pomc) gene fragments. Species tree and concatenation methods were used to infer phylogenetic relationships and divergence times. Phylogenies were used for biogeographical inference using S- DIVA, DEC and BBM. Results Psammodromus probably originated in Iberia, with P. algirus diverging early. The ancestor of the African P. blanci and P. microdactylus dispersed to Africa through the Betic-Rif massif, c. 10 Ma. The cladogenetic events within Africa and Iberia were probably due to vicariance mediated by habitat and climatic changes at the end of the Miocene ( P. blanci and P. microdactylus) and during the Pliocene ( P. occidentalis, P. hispanicus and P. edwardsianus). Psammodromus algirus shows three lineages, two in Iberia and one in Africa, the latter originated following a transmarine dispersal during the Middle Pleistocene (1.5 Ma). Main conclusions Over-sea dispersal has played a major role in intercontinental exchange and divergence in Psammodromus, with two dispersal events towards Africa that occurred 10 and 1.5 Ma resulting in the African lineages. This study, combined with previous literature, provides compelling evidence that major biotic exchanges took place across the Strait of Gibraltar well before or long after the land connection during the Messinian Salinity Crisis ( MSC, 5.9-5.33 Ma). These findings suggest caution in the application of the relatively short event of Atlantic flooding at the end of the MSC as cause for divergence in molecular clock calibrations, which is a popular approach in literature. [ABSTRACT FROM AUTHOR]

Aim Human-assisted range expansion of animals to new environments can lead to phenotypic shifts over ecological time-scales. We investigated whether phenotypic changes are sex-specific using an invasive lizard ( Lampropholis delicata). Location Pacific region (Hawaiian Islands, Lord Howe Island, New Zealand, eastern Australia). Methods Using our knowledge of the introduction history of L. delicata, we examined museum specimens of individuals collected across the native and introduced range to determine whether shifts in morphology or colour pattern polymorphism had occurred during its range expansion, and if so, whether they differed between the sexes. Results Sexual dimorphism in both size and shape was documented within the native range of the delicate skink. However, during range expansion, phenotypic shifts were observed in shape, but not size. In two of the three invasive populations, these phenotypic shifts were sex-specific. In the Hawaiian Islands, changes in shape were driven by males, whereas in New Zealand it was due to shifts in females. Similarly, changes in the frequency of a colour pattern polymorphism, a mid-lateral stripe shown to have sex-specific impacts on fitness (positive in females, negative in males), occurred following colonization of the Hawaiian Islands and Lord Howe Island. In Hawaii, the incidence of the polymorphism increased over time in females, and decreased in males. Main conclusions Phenotypic shifts during the range expansion of invasive species may be sex-specific, and are potentially related to the degree of realized niche shift that has occurred between the source and introduced range. [ABSTRACT FROM AUTHOR]

Multimodal communication involves the use of signals and cues across two or more sensory modalities. The genus Liolaemus (Iguania: Liolaemidae) offers a great potential for studies on the ecology and evolution of multimodal communication, including visual and chemical signals. In this study, we analyzed the response of male and female Liolaemus pacha to chemical, visual and combined (multimodal) stimuli. Using cue-isolation tests, we registered the number of tongue flicks and headbob displays from exposure to signals in each modality. Number of tongue flicks was greater when a chemical stimulus was presented alone than in the presence of visual or multimodal stimuli. In contrast, headbob displays were fewer in number with visual and chemical stimuli alone, but significantly higher in number when combined. Female signallers triggered significantly more tongue flicks than male signallers, suggesting that chemical cues are involved in sexual recognition. We did not find an inhibition between chemical and visual cues. On the contrary, we observed a dominance of the chemical modality, because when presented with visual stimuli, lizards also responded with more tongue flicks than headbob displays. The total response produced by multimodal stimuli was similar to that of the chemical stimuli alone, possibly suggesting non-redundancy. We discuss whether the visual component of a multimodal signal could attract attention at a distance, increasing the effectiveness of transmission and reception of the information in chemical cues. [ABSTRACT FROM AUTHOR]

Widespread niche convergence suggests that species can be organized according to functional trait combinations to create a framework analogous to a periodic table. We compiled ecological data for lizards to examine patterns of global and regional niche diversification, and we used multivariate statistical approaches to develop the beginnings for a periodic table of niches. Data (501 variables) for five major niche dimensions (habitat, diet, life history, metabolism, defense) were compiled for 134 species of lizards representing 24 of the 38 extant families. Principal coordinates analyses were performed on niche dimensional data sets, and species scores for the first three axes were used as input for a principal components analysis to ordinate species in continuous niche space and for a regression tree analysis to separate species into discrete niche categories. Three-dimensional models facilitate exploration of species positions in relation to major gradients within the niche hypervolume. The first gradient loads on body size, foraging mode, and clutch size. The second was influenced by metabolism and terrestrial versus arboreal microhabitat. The third was influenced by activity time, life history, and diet. Natural dichotomies are activity time, foraging mode, parity mode, and habitat. Regression tree analysis identified 103 cases of extreme niche conservatism within clades and 100 convergences between clades. Extending this approach to other taxa should lead to a wider understanding of niche evolution. [ABSTRACT FROM AUTHOR]

The complex orogenic history and structure of Southern South America, coupled with Pleistocene glacial cycles, have generated paleoclimatic and environmental changes that influenced the spatial distribution and genetic composition of natural populations. Despite the increased number of phylogeographic studies in this region and given the frequent idiosyncratic phylogeographic patterns, there is still the need to focus research especially on species that are currently distributed within a wide range of bioclimatic regimes, and that historically have been subject to contrasting scenarios. Liolaemus tenuis is a widely distributed lizard species inhabiting latitudinally in almost 1000 km through central and southern Chile. Here we describe the geographical patterns of genetic variation and lineage diversification within L. tenuis , and their association with geography and Pleistocene glaciations, using sequences from one mitochondrial and two nuclear genes, and five microsatellite loci, and covering most of the species distributional range. Our results revealed a high diversity both within and among populations, as well as two phylogeographic breaks, which are consistent with two of the larger rivers of central Chile, the Maipo and Biobío Rivers. Liolaemus tenuis is characterized by several allopatric lineages, especially in its north and central range, which suggest a history of multiple vicariance processes. Conversely, populations found in the southern range, south of the Biobío River, show signatures of recent decreases in effective population sizes, coupled with recent range expansions and secondary contact. Niche “envelope” data are consistent with patterns of genetic variation; both suggest a history of discontinuous areas of relatively stable populations throughout all of the distribution of L. tenuis . These data are also consistent with higher probabilities of habitat suitability north of the Maipo River (ca. 33°S), in both coastal areas and the “Intermediate Depression” between 34° and 37°S, as well as in the southern Coastal Cordillera between the Biobío and Araucanía regions. Interestingly, both molecular and niche envelope modeling data suggest that some populations may have persisted in fragmented refugia in Andean valleys, within the limits of the ice sheet. Finally, our results suggest that several populations of L. tenuis colonized glaciated regions from refugial areas in lowlands and coastal regions, and in the southern distribution, historic migration events would have occurred from refugial areas within the limits of the ice sheet. [ABSTRACT FROM AUTHOR]

An exceptional new specimen of the stem-basilisk Geiseltaliellus maarius from the middle Eocene of Messel, Germany, preserves details of the squamation of this extinct species. The dorsum and extremities were covered by small, rhomoidal scales, about 0.2 mm in size in most places; somewhat larger scales were present on the lower extremities and on the head. Scales of the venter were arranged in transverse rows, unlike in extant Polychrus and Laemanctus. There is some evidence that the scales on the extremities possessed keels, as in extant basilisks and Polychrus. Keratin appears to be preserved in places. The "Oberhäutchen" is nearly featureless, probably the result of postmortem microbial decomposition; scale organs were not observed. Overall, the body of G. maarius possessed a fine, homogeneous squamation most similar to Basiliscus. Possible sexual dimorphism in the form of the parietal crest raises the prospect of a projecting median keel composed of skin in male G. maarius, although direct evidence on this point is currently lacking. The squamation of the tail is discussed in light of the pseudoautotomy shown by this species. [ABSTRACT FROM AUTHOR]

Comparisons of biodiversity patterns within lineages that occur across major climate gradients and biomes, can provide insights into the relative roles that lineage history, landscape and climatic variation, and environmental change have played in shaping regional biotas. In Australia, while there has been extensive research into the origins and patterns of diversity in the Australian Arid Zone (AAZ), how diversity is distributed across this biome and the Australian Monsoonal Tropics (AMT) to the north, has been less studied. We compared the timing and patterns of diversification across this broad aridity gradient in a clade of lizards ( Strophurus : phasmid geckos) that only occur in association with a unique Australian radiation of sclerophyllous grasses ( Triodia : spinifex). Our results indicate that overall genetic diversity is much higher, older and more finely geographically structured within the AMT, including distantly related clades endemic to the sandstone escarpments of the Kimberley and Arnhem Plateau. Niche modelling analyses also suggest that the distribution of taxa in the AMT is more strongly correlated with variation in topographic relief than in the AAZ. The two broad patterns that we recovered – (i) lineage endemism increases as latitude decreases, and (ii) endemism is tightly correlated to rocky regions – parallel and corroborate other recent studies of habitat generalists and specialised saxicoline lineages occurring across these same regions. Early Miocene diversification estimates also suggest that, soon after Triodia grasses colonised Australia and began to diversify in the Miocene, phasmid geckos with Gondwanan ancestry shifted into these grasses, and have subsequently remained closely associated with this unique vegetation type. [ABSTRACT FROM AUTHOR]

Behavioral thermoregulation is an important mechanism allowing ectotherms to respond to thermal variations. Its efficiency might become imperative for securing activity budgets under future climate change. For diurnal lizards, thermal microhabitat variability appears to be of high importance, especially in hot deserts where vegetation is highly scattered and sensitive to climatic fluctuations. We investigated the effects of a shading gradient from vegetation on body temperatures and activity timing for two diurnal, terrestrial desert lizards, Ctenotus regius, and Morethia boulengeri, and analyzed their changes under past, present, and future climatic conditions. Both species' body temperatures and activity timing strongly depended on the shading gradient provided by vegetation heterogeneity. At high temperatures, shaded locations provided cooling temperatures and increased diurnal activity. Conversely, bushes also buffered cold temperature by saving heat. According to future climate change scenarios, cooler microhabitats might become beneficial to warm-adapted species, such as C. regius, by increasing the duration of daily activity. Contrarily, warmer microhabitats might become unsuitable for less warm-adapted species such as M. boulengeri for which midsummers might result in a complete restriction of activity irrespective of vegetation. However, total annual activity would still increase provided that individuals would be able to shift their seasonal timing towards spring and autumn. Overall, we highlight the critical importance of thermoregulatory behavior to buffer temperatures and its dependence on vegetation heterogeneity. Whereas studies often neglect ecological processes when anticipating species' responses to future climate change the strongest impact of a changing climate on terrestrial ectotherms in hot deserts is likely to be the loss of shaded microhabitats rather than the rise in temperature itself. We argue that conservation strategies aiming at addressing future climate changes should focus more on the cascading effects of vegetation rather than on shifts of species distributions predicted solely by climatic envelopes. [ABSTRACT FROM AUTHOR]

We examined intra- and interspecific variation in functional morphology and whole-organism performance in a sympatric lizard species pair, Iberolacerta horvathi and Podarcis muralis, in the area with a high potential for competition., The biggest variation between species was found in two functional traits, bite force and climbing speed, linked with corresponding morphological traits., The species with larger and taller heads, P. muralis, exhibited correspondingly stronger bite forces. The other species exhibited smaller and flatter head. Both traits may potentially promote segregation between species in trophic niche (stronger bites relate to harder prey) and in refuge use (flatter heads allow using narrower crevices, hence, influencing escaping from common predators). Stronger bites and larger heads also provide one species with a dominant position in interspecific agonistic interactions., Females had longer trunks that impacted negatively on climbing speed, which may lower anti-predator escape abilities of the more trunk-dimorphic species, but positively influence reproductive effort., Our results exemplify how the joint examination of morphological and functional traits of ecologically similar and sympatric species can provide a mechanistic background for understanding their coexistence, namely, syntopic populations that are frequent in the study area., The identified roles of functional morphology in this system of sympatric rock lizards support the contribution of functional diversification for the complexity of community structure via coexistence., A is available for this article. [ABSTRACT FROM AUTHOR]

Signaling species occurring in sympatry are often exposed to similar environmental constraints, so similar adaptations to enhance signal efficacy are expected. However, potentially opposing selective pressures might be present to ensure species recognition. Here, we analyzed the movement-based signals of two pairs of sympatric lizard species to consider how reliable communication is maintained while avoiding misidentification. Our novel approach allows us to quantify signal contrast with plant motion noise at any site we measure, including those utilized by other species. Ctenophorus caudicinctus and Gowidon longirostris differed in display complexity and motor pattern use. They also differed in overall morphology, but their signal contrast scores are strikingly similar. These results demonstrate similar adaptations to their shared environment while maintaining species recognition cues. In contrast, Ctenophorus fordi and Ctenophorus pictus are much closer in appearance, but C. pictus produces considerably higher signal contrast scores, which we suggest is attributable to the absence of territoriality in C. fordi. Taken together, our data provide evidence for adaptation to the local environment in movement-based signals, while also meeting species recognition requirements, but the selective pressure to deal with local conditions is mediated by signal function. [ABSTRACT FROM AUTHOR]

Species distribution modeling is an important tool that uses ecological data to aid in biological conservation. In the present study we used prediction methods, including maximum entropy (Maxent), to project the distribution of the Persian Spider gecko and the impact of climate change on its distribution in Iran. The results were consistent between models and indicated that two of the most important variables in determining distribution of Agamura persica are mean temperature of the wettest quarter and temperature seasonality. All of the models used in this study obtained high area-under-thecurve (AUC) values. Because of the nocturnal behavior of the species, these variables can directly affect species' activity by determining the vegetation type in habitat. Suitable habitats of Agamura persica were in two locations in eastern Iran and a third location in the central plateau. Habitat suitability for this species was increased in the last glacial maximum (LGM), at which time most parts of the Iranian Plateau were suitable (even southwest Iran). However, the suitable habitat area is restricted to the central part of the plateau in the current period. Predictions from four scenarios indicate that future habitat suitability will be patchy and that the central part of the plateau will remain the most important part of the species distribution. [ABSTRACT FROM AUTHOR]

Biased sex ratios, or unequal numbers of males and females in a population, can alter the intensity of sexual selection by enhancing competition for mates, and thus may affect the evolution of reproductive strategies. Studies of sex ratio variation across a clade provide an opportunity to examine the morphological or behavioral consequences of different levels of sexual selection. We examined sex ratio variation, using phylogenetic comparative methods, across a diverse clade of terrestrial vertebrates, the Anolis lizards. Across a sample of 14 species in 21 localities, we found remarkable bidirectional variation in sex ratios across the Anolis clade: males are more common in some populations and females in others. However, we find no evidence that sex ratio bias is associated with sexual size dimorphism, a proxy for sexual selection. Nor do we find an association of sex ratio bias with ecological niches (i.e. ecomorphs), which vary in sexual selection pressures and mating systems. The observed inter-specific variation in sex ratio suggests that a balance of different, possibly opposing, factors, including sex-specific dispersal and mortality rates, may play a role in determining population sex ratio. [ABSTRACT FROM AUTHOR]

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Delimiting young species is one of the great challenges of systematic biology, particularly when the species in question exhibit little morphological divergence. Anolis distichus, a trunk anole with more than a dozen subspecies that are defined primarily by dewlap color, may actually represent several independent evolutionary lineages. To test this, we utilized amplified fragment length polymorphisms (AFLP) genome scans and genetic clustering analyses in conjunction with a coalescent-based species delimitation method. We examined a geographically widespread set of samples and two heavily sampled hybrid zones. We find that genetic divergence is associated with a major biogeographic barrier, the Hispaniolan paleo-island boundary, but not with dewlap color. Additionally, we find support for hypotheses regarding colonization of two Hispaniolan satellite islands and the Bahamas from mainland Hispaniola. Our results show that A. distichus is composed of seven distinct evolutionary lineages still experiencing a limited degree of gene flow. We suggest that A. distichus merits taxonomic revision, but that dewlap color cannot be relied upon as the primary diagnostic character. [ABSTRACT FROM AUTHOR]

Patterns of range size evolution are important for developing an evolutionary biogeographical theory and supporting conservation actions. Determining those patterns is however hampered by multiple factors acting on range size and by our uncertainty with regard to species' phylogenetic relationships and geographic distribution. In addition, given the diversity of analytic approaches existing in the literature, there are concerns regarding whether different methods might lead to different patterns. Here, we addressed these uncertainties in order to test for correlations between the evolution of morphology (body size and shape) and range size. We studied lizards of the family Gymnophthalmidae, representing changes of an order of magnitude in body size and also two independent lineages with limb-reduced (snake-like) morphs. We used phylogenetic multivariate methods (pPCA) to control for allometric effects of body size over shape. Then, we performed multiple regressions under three approaches: 'naive' least squares, Bayesian comparative methods that accounted for uncertainties in trait optimization, tree topology and branch length, and a novel permutative procedure based on phylogenetic generalized least squares (pGLS) to assess the robustness of our relationships to uncertainties in the range sizes of the species studied. All approaches led to the same answer: only body size was related to range size. While bigger gymnophthalmids tend to have relatively large ranges, small species can have either small or large ones. Our results' robustness to strong uncertainties in both phylogenetic relationships and range sizes shows there are opportunities for overcoming those problems and produce reliable patterns of range size evolution. However, interpretation of the processes driving patterns of range size evolution will still require advances in phylogenetic and taxonomic knowledge. We discuss the application of morphology-range size relationships to conservation planning in the light of existing uncertainties in the geographic knowledge of our studied species group and workarounds for data availability. [ABSTRACT FROM AUTHOR]

During a trip to Fuerteventura and the small Island of Lobos in June 2016, the herpetofauna and flora was investigated. I found the subspecies Gallotia atlantica mahoratae and the introduced population of Gallotia galloti eisentrauti in Esquinzo. The Skink Chalcides simonyi and the introduced population of the Gran Canaria Lizard Gallotia stehlini could not be found during the trip. [ABSTRACT FROM AUTHOR]

The Ibizan wall lizard, Podarcis pityusensis, was the subject of several documented translocations by the German vertebrate zoologist Martin Eisentraut, in 1930. He aimed to initiate long-term experiments into the evolution of melanism and other morphological traits and accordingly he designed introductions into five islets that (he believed) contained no lizards. In this study, we analyzed the genetic and morphological characteristics of individuals we found there. We found no lizards on two of the islets, namely Escull de Tramuntana and Galera, but for the first time, detected a large population on a third islet, Es Vaixell. Eisentraut founded the Es Vaixell population with nonmelanistic Ibizan specimens, but the present day population of Es Vaixell was found to be fully melanistic. Genetic markers support a strong similarity between Es Vaixell and its neighbour islet, Na Gorra, and indicate that, in all likelihood, the individuals introduced by Eisentraut have left no descendants. It is likely that Es Vaixell already contained lizards prior to this introduction. Analyses of microsatellite DNA placed individuals from a fourth islet, Dau Gran, with those of one of its source islet, Escull Vermell. They are also morphologically close to individuals from Escull Vermell. This suggests that selection pressures could have favoured the Escull Vermell phenotype following introduction. For reasons we discuss, the translocations have revealed less than Eisentraut would have originally hoped for. Although evolutionary processes are normally time-consuming, these translocations do provide some potential insights into the rapid evolution of lizard morphology following colonization. [ABSTRACT FROM AUTHOR]