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Abstract

Our knowledge of the conservation status of reptiles, the most diverse class of terrestrial vertebrates, has improved dramatically over the past decade, but still lags behind that of the other tetrapod groups. Here, we conduct the first comprehensive evaluation (~92% of the world's ~1714 described species) of the conservation 1 Joint senior authors. D.G. Chapple et al. Biological Conservation 257 (2021) 109101 3 Lizard Protected areas Reptile Skink Taxonomic bias status of skinks (Scincidae), a speciose reptile family with a worldwide distribution. Using International Union for Conservation of Nature (IUCN) criteria, we report that ~20% of species are threatened with extinction, and nine species are Extinct or Extinct in the Wild. The highest levels of threat are evident in Madagascar and the Neotropics, and in the subfamilies Mabuyinae, Eugongylinae and Scincinae. The vast majority of threatened skink species were listed based primarily on their small geographic ranges (Criterion B, 83%; Criterion D2, 13%). Although the population trend of 42% of species was stable, 14% have declining populations. The key threats to skinks are habitat loss due to agriculture, invasive species, and biological resource use (e.g., hunting, timber harvesting). The distributions of 61% of species do not overlap with protected areas. Despite our improved knowledge of the conservation status of the world's skinks, 8% of species remain to be assessed, and 14% are listed as Data Deficient. The conservation status of almost a quarter of the world's skink species thus remains unknown. We use our updated knowledge of the conservation status of the group to develop and outline the priorities for the conservation assessment and management of the world's skink species.

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... In addition to their nearly global distribution, skink species occur in high numbers in species richness hotspots commonly known for lizards (Roll et al., 2017). The highest species richness of skinks is in Australia, New Guinea, Southeast Asia, Sub-Saharan Africa, and Madagascar (Chapple et al., 2021). Their wide distribution is reflected by their ecological diversity and the great variety of their habitats. ...
... The Global Reptile Assessment project in recent years has begun to fill this gap (NatureServe, 2021). For skinks in particular, the establishment of the IUCN Skink Specialist Group (SSG) in 2018, a global network of biologists and wildlife managers with over 160 members actively involved in skink research, was an important step towards filling knowledge gaps and protecting skinks (Skink Specialist Group, 2021). The objectives of the SSG are, on the one hand, to monitor and update the Red List assessments for all skinks and thus to obtain an overview of the endangerment of skink species (Chapple et al., 2021). ...
... For skinks in particular, the establishment of the IUCN Skink Specialist Group (SSG) in 2018, a global network of biologists and wildlife managers with over 160 members actively involved in skink research, was an important step towards filling knowledge gaps and protecting skinks (Skink Specialist Group, 2021). The objectives of the SSG are, on the one hand, to monitor and update the Red List assessments for all skinks and thus to obtain an overview of the endangerment of skink species (Chapple et al., 2021). In this way, the threat factors and threatened species are to be identified. ...
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Abstract To manage populations of threatened species according to the IUCN’s One Plan Approach, knowledge about both in situ and ex situ populations is required. To enhance the conservation of threatened skinks and to gain an overview which skink species are kept in zoos, and thus already have an ex situ conservation component, we analysed data from the Zoological Information Management System (ZIMS): their individual numbers, breeding success, and the number of holding institutions. We categorised species as threatened or non-threatened based on IUCN Red List assessments. Only 92 (~5%) of 1727 recognized skink species are held in ZIMS institutions worldwide, mostly in Australia, Europe, and North America. 77% of the species kept globally are classified as non-threatened and ~23% (21 species) are threatened. Only 28% of the species kept have successfully bred in the last year, mostly in one zoo each. Of these seven species were threatened. All threatened species are kept by four zoos at most, generally only in one. Half of the skink species kept are represented by less than 10 individuals. Mainly Australian skink species were kept. To improve the conservation of threatened skinks, a shift towards keeping threatened species should be considered within captive management programmes. European and North American zoos offer capacities and expertise for skink conservation but are outside skink species richness hotspots. Cooperative projects with institutions and stations in such hotspots could greatly benefit the conservation of skinks. Thus, according to the One Plan Approach, the ex situ populations could directly contribute to in situ protection.
... Across all analyses, small, and especially insular, distributions consistently emerge as key predictors of conservation concern. Indeed, insular areas such as the Pacific islands, Madagascar, and New Zealand have some of the most threatened biotas in the world (Carlquist 1974;Cheke and Hume 2008;Chapple et al. 2021). Accordingly, for taxa wherein insular distributions intersect with high levels of undescribed diversity and cryptic ecologies, CER may be acute. ...
... To broadly assess the degree to which Lepidodactylus may be less known and/or more threatened than other reptile taxa, we compared the percentages of threatened and data deficient species to similar studies, which have synthetically revised the conservation status of groups of reptiles (Böhm et al. 2013;Tingley et al. 2019;Chapple et al. 2021). ...
... We found twenty-one (36%) of the described Lepidodactylus species to be DD, with insufficient data preventing adequate assessment of conservation status. This percentage is higher than the global percentages of DD reptiles reported at the Order level (0-24%, except for Amphisbaenia) and realm (0-33%) (Böhm et al. 2013), higher than any of the world's skink subfamilies (3-15%) (Chapple et al. 2021), higher than any reptile family in Australia (0-18%) (Tingley et al. 2019), and higher than 25 of 26 reptile Families in Tanzania (0-27%). West Melanesia had the highest number of DD species (n = 6) (Fig. 2). ...
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Cryptic ecologies, the Wallacean Shortfall of undocumented species' geographical ranges and the Linnaean Shortfall of undescribed diversity, are all major barriers to conservation assessment. When these factors overlap with drivers of extinction risk, such as insular distributions, the number of threatened species in a region or clade may be underestimated, a situation we term 'cryptic extinction risk'. The genus Lepidodactylus is a diverse radiation of insular and arboreal geckos that occurs across the western Pacific. Previous work on Lepidodactylus showed evidence of evolutionary displacement around continental fringes, suggesting an inherent vulnerability to extinction from factors such as competition and predation. We sought to (1) comprehensively review status and threats, (2) estimate the number of undescribed species, and (3) estimate extinction risk in data deficient and candidate species, in Lepidodactylus. From our updated IUCN Red List assessment, 60% of the 58 recognized species are threatened (n = 15) or Data Deficient (n = 21), which is higher than reported for most other lizard groups. Species from the smaller and isolated Pacific islands are of greatest conservation concern, with most either threatened or Data Deficient, and all particularly vulnerable to invasive species. We estimated 32 undescribed candidate species and linear modelling predicted that an additional 18 species, among these and the data deficient species, are threatened with extinction. Focusing efforts to resolve the taxonomy and conservation status of key taxa, especially on small islands in the Pacific, is a high priority for conserving this remarkably diverse, yet poorly understood, lizard fauna. Our data highlight how cryptic ecologies and cryptic diversity combine and lead to significant underestimation of extinction risk. Supplementary information: The online version contains supplementary material available at 10.1007/s10531-022-02412-x.
... An important approach to generate transferable knowledge has been to use traits to identify groups of species that are vulnerable to the effects of habitat disturbance (Keinath et al. 2017). For reptiles-a group threatened by habitat loss, fragmentation and modification (Keinath et al. 2017;Doherty et al. 2020), particularly agriculture (Chapple et al. 2021;Wong et al. 2021)-a range of traits have proven useful in discriminating responses, including body size, reproduction, diet, habitat position and activity period (Watling and Donnelly 2007;Santos and Cheylan 2013;Carvajal-Cogollo and Urbina-Cardona 2015;Bohm et al. 2016;Neilly et al. 2018;Val et al. 2019;Chergui et al. 2020;Williams et al. 2021b). While substantial research effort has been directed towards understanding the role of traits in explaining reptile responses to disturbance, consistent trends have not yet emerged. ...
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Context Habitat loss and fragmentation can interact with other threats, including altered fire regimes, and responses to these effects can be mediated by functional traits. Objectives To determine how richness and abundance of reptile trait groups respond to habitat fragmentation, patch isolation and fire. Methods We surveyed reptiles in 30 sites over 3 years. Sites in remnant patches in farmland were adjacent to a conservation park with either recently burnt or long-unburnt habitat. The remnant patches were stratified by distance from the reserve. Sites were spatially paired, and we experimentally burnt one of each pair in farmland. Trait groups included size, reproduction, habitat position, diet, and activity period. Results None of the trait groups benefited from experimental burns, while the burns reduced abundance of viviparous, small, and above-ground species. Species richness was lower in isolated sites than in sites close to the conservation park, while generalist trait groups appeared unaffected by patch isolation. Large-sized reptiles had higher abundance in remnants. There was not more rapid colonisation of burnt sites near recently burnt conservation park. Instead, low initial abundance may have been caused by fire in combination with drought, with high rainfall during the study allowing recovery and spill-over into adjacent remnants. Conclusions Landscape structure appears to interact with natural fires, restoration burns and longer-term climatic trends to influence the abundance and distribution of reptiles. Traits mediate responses, enabling us to formulate a set of testable mechanistic hypotheses, which illustrates a pathway to generalisation and prediction.
... The International Union for Conservation of Nature (IUCN) is the primary source for species conservation categories (Red List of Threatened Species), and the criteria and guidelines needed to establish them (IUCN, 2012a,b). Only ~40% of reptiles have been assessed by the IUCN (Meiri & Chapple, 2016), and this group has received markedly less attention than other groups of vertebrates like amphibians, birds and mammals (Chapple et al., 2021). Additionally, once a species assessment is carried out by the IUCN, an update might be needed if new data becomes available (e.g. ...
... Skinks (Scincidae) comprise the largest family of lizards, with 1727 species currently described worldwide (Uetz et al. 2021). They occur in almost all terrestrial habitats and display remarkable ecological diversity (Chapple et al. 2021). Most species are diurnal, but many are nocturnal or cathemeral (Vitt and Caldwell 2014). ...
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Many animals have strict diel activity patterns, with unique adaptations for either diurnal or nocturnal activity. Diel activity is phylogenetically conserved, yet evolutionary shifts in diel activity occur and lead to important changes in an organism's morphology, physiology, and behaviour. We use phylogenetic comparative methods to examine the evolutionary history of diel activity in skinks, one of the largest families of terrestrial vertebrates. We examine how diel patterns are associated with microhabitat, ambient temperatures, and morphology. We found support for a non‐diurnal ancestral skink. Strict diurnality in crown group skinks only evolved during the Paleogene. Nocturnal habits are associated with fossorial activity, limb reduction and loss, and warm temperatures. Our results shed light on the evolution of diel activity patterns in a large radiation of terrestrial ectotherms and reveal how both intrinsic biotic and extrinsic abiotic factors can shape the evolution of animal activity patterns. This article is protected by copyright. All rights reserved
... Several reptile species are showing declines in north Australia, apparently more so than in southern regions [49]. Three are critically endangered (Austroblepharus barrylyoni; Bellatorias obiri; Lerista allanae), two endangered (Saltuarius eximius; Lerista ameles), one vulnerable (Orraya occultus), and one is considered by expert elicitation to be vulnerable (Lerista storri) [49], but most reptiles seem to be secure [50]. ...
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Northern Australian biomes hold high biodiversity values within largely intact vegetation complexes, yet many species of mammals, and some other taxa, are endangered. Recently, six mammal species were added to the 20 or so already listed in the Australian endangered category. Current predictions suggest that nine species of mammal in northern Australia are in imminent danger of extinction within 20 years. We examine the robustness of the assumptions of status and trends in light of the low levels of monitoring of species and ecosystems across northern Australia, including monitoring the effects of management actions. The causes of the declines include a warming climate, pest species, changed fire regimes, grazing by introduced herbivores, and diseases, and work to help species and ecosystems recover is being conducted across the region. Indigenous custodians who work on the land have the potential and capacity to provide a significant human resource to tackle the challenge of species recovery. By working with non-Indigenous researchers and conservation managers, and with adequate support and incentives, many improvements in species' downward trajectories could be made. We propose a strategy to establish a network of monitoring sites based on a pragmatic approach by prioritizing particular bioregions. The policies that determine research and monitoring investment need to be re-set and new and modified approaches need to be implemented urgently. The funding needs to be returned to levels that are adequate for the task. At present resourcing levels, species are likely to become extinct through an avoidable attrition process .
... Including undescribed taxa there are at least 61 extant skink species and 43 extant gecko species, all of which are endemic (Hitchmough, Barr, et al., 2016;Hitchmough, Patterson, et al., 2016). This lizard diversity is remarkable for a temperate region (Chapple, 2016;Hitchmough, Barr, et al., 2016;Hitchmough, Patterson, et al., 2016), and many species have life-history traits such as large body size, low reproductive output and late maturity that may make them particularly vulnerable to climate change (Chapple et al., 2021;Hoffmann & Sgrò, 2011;Nelson et al., 2014;Sinervo et al., 2010;Whitaker, 1978). Numerous species have experienced substantial range reductions following human settlement and the introduction of mammalian predators, while others have apparently naturally restricted distributions (Hitchmough, Barr, et al., 2016;Hitchmough, Patterson, et al., 2016;Nelson et al., 2014). ...
Article
The primary drivers of species and population extirpations have been habitat loss, overexploitation and invasive species, but human‐mediated climate change is expected to be a major driver in future. To minimise biodiversity loss, conservation managers should identify species vulnerable to climate change and prioritise their protection. Here, we estimate climatic suitability for two species‐rich taxonomic groups, then use phylogenetic analyses to assess vulnerability to climate change. Aotearoa New Zealand (NZ). NZ lizards: diplodactylid geckos and eugongylinae skinks. We built correlative species distribution models (SDMs) for NZ geckos and skinks to estimate climatic suitability under current climate and 2070 future climate scenarios. We then used Bayesian phylogenetic mixed models (BPMMs) to assess vulnerability for both groups with predictor variables for life‐history traits (body size and activity phase) and current distribution (elevation and latitude). We explored two scenarios: an unlimited dispersal scenario, where projections track climate, and a no‐dispersal scenario, where projections are restricted to areas currently identified as suitable. SDMs projected vulnerability to climate change for most modelled lizards. For species' ranges projected to decline in climatically suitable areas, average decreases were between 42% and 46% for geckos and 33% and 52% for skinks, although area did increase or remain stable for a minority of species. For the no‐dispersal scenario, the average decrease for geckos was 37%–52% and for skinks was 33%–52%. Our BPMMs showed phylogenetic signal in climate change vulnerability for both groups, with elevation increasing vulnerability for geckos, and body size reducing vulnerability for skinks. New Zealand lizards showed variable vulnerability to climate change, with most species' ranges predicted to decrease. For species whose suitable climatic space is projected to disappear from within their current range, managed relocation could be considered to establish populations in regions that will be suitable under future climates.
... 'Near Threatened' or higher status) of the more than 1715 species worldwide (Uetz et al. 2020). Australia is a centre for Scincidae diversity (Chapple et al. 2021). Skinks exhibit diverse reproductive strategies and physiology, from viviparous to oviparous, as well as mixed strategies between the two (Blackburn 2015;Laird et al. 2019). ...
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Assisted reproductive technologies for population and genetic management for threatened herpetofauna have grown substantially in the past decade. Here we describe experiments to optimise sperm cryopreservation in a model squamate, the eastern water skink Eulamprus quoyii. Small, concentrated volumes of highly motile spermatozoa were reliably collected from adult male E. quoyii by non-lethal ventral massage. Samples were used to: (1) test whether protein-rich diluents, namely Beltsville poultry semen extender (BPSE) and TES and Tris (TEST) yolk buffer (TYB), improve post-thaw quality metrics compared with Dulbecco's phosphate-buffered saline (DPBS); and (2) compare the efficacy of these diluents in combination with either 1.35M glycerol or 1.35M dimethyl sulfoxide (DMSO) at two freezing rates, fast (approximately -20°C min-1) versus slow (-6°C min-1). Glycerol and DMSO performed equally well in preserving spermatozoa under slow freezing rates. Under these conditions, the use of the complex diluents BPSE and TYB significantly improved post-thaw total motility compared with DPBS. Complex interactions occurred between cryodiluent type, cryoprotectant and freezing rate when testing fast versus slow freezing rates among treatment groups. Under slow freezing rates, DMSO was better at preserving membrane integrity and motility, regardless of diluent type, but successful fast freezing required complex diluents to support motility and membrane integrity, which has implications for implementation in a field setting.
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Limb‐reduced squamates are a convenient model system to investigate macroevolutionary trends in morphology. Here, we provide morphological, ecological and literature data on all known species of limb‐reduced skinks (Scincidae) and their relatives, representing one of the most diverse and widely distributed groups of limb‐reduced squamates. Global. Skinks (Reptilia, Squamata: Scincidae). Limb‐reduced forms. Morphological data were sourced from the primary literature, spanning a period of over 150 years. Linear body measurements were averaged across all values in the literature, preserving proportionality to body length. For digits and presacral vertebrae, we used maximum recorded counts. Ecological and biogeographical data were sourced from habitat assessments in the primary literature, online databases and field guides. Literature data were sorted according to type of study. To exemplify the applicability of the database, we used Markov‐chain ordered models to estimate the evolutionary frequency of limb reduction and loss in skinks. We find evidence of limb reduction and loss in a total of 394 species worldwide, representing ~23% of all skink species, and ~30% of genera. The distribution of limb‐reduced and limbless forms differs from that of fully limbed forms, as they are present in all biogeographic realms with the almost complete exclusion of the Americas. We estimate that limb reduction evolved more than 50 times in skinks, and that loss of at least one limb pair evolved at least 24 times. The dataset captures a broad spectrum of morphological and ecological variation in a large, globally distributed taxonomic group. It establishes a widely applicable definition of limb reduction based on limb proportions as a reference for future studies. Such an extensive collection of morphological and ecological data can pave the way for investigations of dramatic morphological transitions and their ecological drivers at a global and local scale.
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Phylogenetic diversity measures are increasingly used in conservation planning to represent aspects of biodiversity beyond that captured by species richness. Here we develop two new metrics that combine phylogenetic diversity and the extent of human pressure across the spatial distribution of species-one metric valuing regions and another prioritising species. We evaluate these metrics for reptiles, which have been largely neglected in previous studies, and contrast these results with equivalent calculations for all terrestrial vertebrate groups. We find that regions under high human pressure coincide with the most irreplaceable areas of reptilian diversity, and more than expected by chance. The highest priority reptile species score far above the top mammal and bird species, and reptiles include a disproportionate number of species with insufficient extinction risk data. Data Deficient species are, in terms of our species-level metric, comparable to Critically Endangered species and therefore may require urgent conservation attention.
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Historically, an understanding of viviparity and its evolution in Old World chameleons (Chamaeleonidae) has lagged behind that of other squamate families. Not only is reproductive information scarce or entirely absent for most chameleon species, but the literature reveals no consensus as to the frequency and ecological circumstances under which chameleon viviparity evolved. We integrated information on reproductive modes for nearly all chameleon species with recently published family‐scale phylogenetic and ecological analyses to clarify aspects of reproductive evolution in chameleons. Ancestral‐trait reconstructions, after accounting for phylogenetic uncertainty, indicated that viviparity has arisen a minimum of three times in Chamaeleonidae, with each origin of live birth in closed‐canopy forests. Our maximum‐likelihood optimization therefore did not support the previous hypotheses of one, two or four origins of viviparity in the family. Past claims that arboreality would not allow for evolution of viviparity were also not supported, nor was a recent suggestion that viviparity has reverted to oviparity. However, cold climates of high latitudes and elevations may have selected for viviparity in arboreal chameleons. While peritoneal pigmentation may facilitate viviparity, its role as an exaptation rather than an adaptation remains equivocal without data from a wider range of chameleon species. Based on a comprehensive review of reproductive modes throughout the family, our study has resolved the number of origins of viviparity in Chamaeleonidae and provided evidence that live birth evolved under arboreal conditions on three separate occasions in this enigmatic squamate group. This study also reveals the value of using phylogenetic analysis in a manner that is robust to uncertainty (rather than simple correlational approaches) when the goal is to reconstruct evolutionary sequences and selective pressures. We found three origins of viviparity in Chamaeleonidae, with each origin of live birth in closed‐canopy forests. Past claims that arboreality would not allow for evolution of viviparity were not supported, nor was a recent suggestion that viviparity has reverted to oviparity in chameleons. This study highlights the value of using phylogenetic comparative analysis in a manner that is robust to uncertainty when the goal is to reconstruct evolutionary sequences and selective pressures.
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Context. Feral cats (Felis catus) are a threat to biodiversity globally, but their impacts upon continental reptile faunas have been poorly resolved. Aims. To estimate the number of reptiles killed annually in Australia by cats and to list Australian reptile species known to be killed by cats. Methods. We used (1) data from>80 Australian studies of cat diet (collectively>10 000 samples), and (2) estimates of the feral cat population size, to model and map the number of reptiles killed by feral cats. Key results. Feral cats in Australia's natural environments kill 466 million reptiles yr⁻¹ (95% CI; 271-1006 million). The tally varies substantially among years, depending on changes in the cat population driven by rainfall in inland Australia. The number of reptiles killed by cats is highest in arid regions. On average, feral cats kill 61 reptileskm⁻² year⁻¹, and an individual feral cat kills 225 reptiles year⁻¹. The take of reptiles per cat is higher than reported for other continents. Reptiles occur at a higher incidence in cat diet than in the diet of Australia's other main introduced predator, the European red fox (Vulpes vulpes). Based on a smaller sample size, we estimate 130 million reptiles year⁻¹ are killed by feral cats in highly modified landscapes, and 53 million reptiles year⁻¹ by pet cats, summing to 649 million reptiles year⁻¹ killed by all cats. Predation by cats is reported for 258 Australian reptile species (about one-quarter of described species), including 11 threatened species. Conclusions. Cat predation exerts a considerable ongoing toll on Australian reptiles. However, it remains challenging to interpret the impact of this predation in terms of population viability or conservation concern for Australian reptiles, because population size is unknown for most Australian reptile species, mortality rates due to cats will vary across reptile species and because there is likely to be marked variation among reptile species in their capability to sustain any particular predation rate. Implications. This study provides a well grounded estimate of the numbers of reptiles killed by cats, but intensive studies of individual reptile species are required to contextualise the conservation consequences of such predation.
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Effective conservation action relies on access to the best-available species data. Reptiles have often been overlooked in conservation prioritization, especially because of a paucity of population data. Using data for 549 reptile populations representing 194 species from the Living Planet database, we provide the first detailed analysis of this database for a specific taxonomic group. We estimated an average global decline in reptile populations of 54-55% between 1970 and 2012. Disaggregated indices at taxonomic, system, and biogeographical levels showed trends of decline, often with wide confidence intervals because of a prevalence of short time series. We assessed gaps in our reptile time-series data and examined what types of publication they primarily originated from to provide an overview of the range of data sources captured in the Living Planet database. Data were biased toward crocodilians and chelonians, with only 1% and 2% of known lizard and snake species represented, respectively. Population time-series data stemmed primarily from published ecological research (squamates) and data collected for conservation management (chelonians and crocodilians). We recommend exploration of novel survey and analytical techniques to increase monitoring of reptiles, especially squamates, over time. Open access publication and sharing of data sets are vital to improve knowledge of reptile status and trends, aided by the provision of properly curated databases and data-sharing agreements. Such collaborative efforts are vital to effectively address global reptile declines.
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Several species of lizards from the megadiverse island of New Guinea have evolved green blood. An unusually high concentration of the green bile pigment biliverdin in the circulatory system of these lizards makes the blood, muscles, bones, tongue, and mucosal tissues bright green in color, eclipsing the crimson color from their red blood cells. This is a remarkable physiological feature because bile pigments are toxic physiological waste products of red blood cell catabolism and, when chronically elevated, cause jaundice in humans and all other vertebrates. Although these lizards offer a promising system to examine the evolution of extraordinary physiological characteristics, little is known about the phylogenetic relationships of green-blooded lizards or the evolutionary origins of green blood. We present the first extensive phylogeny for green-blooded lizards and closely related Australasian lizards using thousands of genomic regions to examine the evolutionary history of this unusual trait. Maximum likelihood ancestral character state reconstruction supports four independent origins of green blood. Our results lay the phylogenetic foundation necessary to determine the role, if any, of natural selection in shaping this enigmatic physiological trait as well as understanding the genetic, proteomic, and biochemical basis for the lack of jaundice in those species that have independently evolved green blood.
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As we collect range-wide genetic data for morphologically-defined species, we increasingly unearth evidence for cryptic diversity. Delimiting this cryptic diversity is challenging, both because the divergences span a continuum and because the lack of overt morphological differentiation suggests divergence has proceeded heterogeneously. Here, we address these challenges as we diagnose and describe species in three co-occurring species groups of Australian lizards. By integrating genomic and morphological data with data on hybridization and introgression from contact zones, we explore several approaches - and their relative benefits and weaknesses - for testing the validity of cryptic lineages. More generally, we advocate that genetic delimitations of cryptic diversity must consider whether these lineages are likely to be durable and persistent through evolutionary time.
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Aim: Small geographic ranges make species especially prone to extinction from anthropogenic disturbances or natural stochastic events. We assemble and analyse a comprehensive dataset of all the world's lizard species and identify the species with the smallest ranges—those known only from their type localities. We compare them to wide-ranging species to infer whether specific geographic regions or biological traits predispose species to have small ranges. Location: Global. Methods: We extensively surveyed museum collections, the primary literature and our own field records to identify all the species of lizards with a maximum linear geographic extent of <10 km. We compared their biogeography, key biological traits and threat status to those of all other lizards. Results: One in seven lizards (927 of the 6,568 currently recognized species) are known only from their type localities. These include 213 species known only from a single specimen. Compared to more wide-ranging taxa, they mostly inhabit relatively inaccessible regions at lower, mostly tropical, latitudes. Surprisingly, we found that burrowing lifestyle is a relatively unimportant driver of small range size. Geckos are especially prone to having tiny ranges, and skinks dominate lists of such species not seen for over 50 years, as well as of species known only from their holotype. Two-thirds of these species have no IUCN assessments, and at least 20 are extinct. Main conclusions: Fourteen per cent of lizard diversity is restricted to a single location, often in inaccessible regions. These species are elusive, usually poorly known and little studied. Many face severe extinction risk, but current knowledge is inadequate to properly assess this for all of them. We recommend that such species become the focus of taxonomic, ecological and survey efforts.
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The distributions of amphibians, birds and mammals have underpinned global and local conservation priorities, and have been fundamental to our understanding of the determinants of global biodiversity. In contrast, the global distributions of reptiles, representing a third of terrestrial vertebrate diversity, have been unavailable. This prevented the incorporation of reptiles into conservation planning and biased our understanding of the underlying processes governing global vertebrate biodiversity. Here, we present and analyse the global distribution of 10,064 reptile species (99% of extant terrestrial species). We show that richness patterns of the other three tetrapod classes are good spatial surrogates for species richness of all reptiles combined and of snakes, but characterize diversity patterns of lizards and turtles poorly. Hotspots of total and endemic lizard richness overlap very little with those of other taxa. Moreover, existing protected areas, sites of biodiversity significance and global conservation schemes represent birds and mammals better than reptiles. We show that additional conservation actions are needed to effectively protect reptiles, particularly lizards and turtles. Adding reptile knowledge to a global complementarity conservation priority scheme identifies many locations that consequently become important. Notably, investing resources in some of the world’s arid, grassland and savannah habitats might be necessary to represent all terrestrial vertebrates efficiently.
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How organs originate and evolve is a question fundamental to understanding the evolution of complex multicellular life forms. Vertebrates have a relatively standard body plan with more or less the same conserved set of organs. The placenta is a comparatively more recently evolved organ, derived in many lineages independently. Using placentas as a model, we discuss the genetic basis for organ origins. We show that the evolution of placentas occurs by acquiring new functional attributes to existing tissues, changes in the patterning and development of tissues, and the evolution of novel cell types. We argue that a diversity of genomic changes facilitated these physiological transformations and that these changes are likely to have occurred during the evolution of organs more broadly. Finally, we argue that a key aspect to understanding the evolutionary origin of organs is that they are likely to result from novel interactions between distinct cell populations.
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Aim A major Late Quaternary vertebrate extinction event affected mostly large-bodied 'megafauna'. This is well documented in both mammals and birds, but evidence of a similar trend in reptiles is scant. We assess the relationship between body size and Late Quaternary extinction in reptiles at the global level. Location Global. Methods We compile a body size database for all 82 reptile species that are known to have gone extinct during the last 50,000 years and compare them with the sizes of 10,090 extant reptile species (97% of known extant diversity). We assess the body size distributions in the major reptile groups: crocodiles, lizards, snakes and turtles, while testing and correcting for a size bias in the fossil record. We examine geographical biases in extinction by contrasting mainland and insular reptile assemblages, and testing for biases within regions and then globally by using geographically weighted models. Results Extinct reptiles were larger than extant ones, but there was considerable variation in extinction size biases among groups. Extinct lizards and turtles were large, extinct crocodiles were small and there was no trend in snakes. Lizard lineages vary in the way their extinction is related to size. Extinctions were particularly prevalent on islands, with 73 of the 82 extinct species being island endemics. Four others occurred in Australia. The fossil record is biased towards large-bodied reptiles, but extinct lizards were larger than extant ones even after we account for this. Main conclusions Body size played a complex role in the extinction of Late Quaternary reptiles. Larger lizard and turtle species were clearly more affected by extinction mechanisms such as over exploitation and invasive species, resulting in a prevalence of large-bodied species among extinct taxa. Insularity was by far the strongest correlate of recent reptile extinctions, suggesting that size-biased extinction mechanisms are amplified in insular environments.
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Rising rates of extinction create an urgent need to identify the mechanisms and drivers of endangerment. One critical question is whether major phylogenetic lineages are equally at risk to the same threats. We used the IUCN Red List classification to explore the effect of four major threatening processes (habitat alteration, invasive species, climate change and overexploitation) on 7,441 species in four terrestrial vertebrate classes. As expected, species rated as vulnerable to a higher number of threats were also at greater risk of extinction. However, this pattern differed strongly among classes. Notably, invasive species and climate change were strongly associated with increased risk of extinction in birds but not mammals. These large-scale differences might be artifacts of differing methodologies used by class specialists to classify species vulnerability; or might reflect biological differences. That ambiguity needs to be resolved, because it has strong implications for the assessment and amelioration of threatening processes.
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We are concerned at how research agendas of science, and conservation biology in particular, are potentially being deformed by the dominant influence of a single entity, Journal Impact Factors, which in turn reflect the business model of the USA-based global corporate entity Thomson Reuters. We are particularly concerned that this single metric results in systematic suppression of research vital for conservation biology in Australia. We outline the ways by which Journal Impact Factors impact negatively on the kinds of research which underpin the conservation of Australia’s biodiversity. We argue that the influence of this scheme on Australian science needs to be changed. A new formula will require a much greater emphasis on an Australian, not an American, perspective, and a decoupling of the metric of impact factor from a business model for publishing houses.
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How sociality evolves and is maintained remains a key question in evolutionary biology. Most studies to date have focused on insects, birds, and mammals but data from a wider range of taxonomic groups are essential to identify general patterns and processes. The extent of social behaviour among squamate reptiles is under-appreciated, yet they are a promising group for further studies. Living in aggregations is posited as an important step in the evolution of more complex sociality. We review data on aggregations among squamates and find evidence for some form of aggregations in 94 species across 22 families. Of these, 18 species across 7 families exhibited 'stable' aggregations that entail overlapping home ranges and stable membership in long-term (years) or seasonal aggregations. Phylogenetic analysis suggests that stable aggregations have evolved multiple times in squamates. We: (i) identify significant gaps in our understanding; (ii) outline key traits which should be the focus of future research; and (iii) outline the potential for utilising reproductive skew theory to provide insights into squamate sociality. © 2015 Cambridge Philosophical Society.
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Viviparity in squamate reptiles is widely recognized as having evolved convergently from oviparity more than 100 times. However, questions persist as to whether reversals from viviparity back to oviparity have ever occurred. Based on a theoretical model, a recent paper (Pyron and Burbrink, 2014) has proposed that viviparity is ancestral for squamates and that viviparity-oviparity reversals have far outnumbered origins of viviparity in reproductive history. Close examination of this analysis reveals features that cast doubt on its plausibility, notably the requirement of repeated, sequential transformations back and forth between these reproductive modes, as well as numerous, uncounted evolutionary transformations that have produced inaccurate estimates of parsimony. Evidence derived from studies of anatomy, physiology, and developmental biology strongly supports the inference that oviparity is ancestral for squamates and has given rise to viviparity on numerous occasions. Biological data provide important insights into the likelihood of evolutionary transformations, and deserve to be incorporated fully into future analyses of the evolution of reproductive modes. J. Exp. Zool. (Mol. Dev. Evol.) 9999B: XX-XX, 2015. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.
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Effective and targeted conservation action requires detailed information about species, their distribution, systematics and ecology as well as the distribution of threat processes which affect them. Knowledge of reptilian diversity remains surprisingly disparate, and innovative means of gaining rapid insight into the status of reptiles are needed in order to highlight urgent conservation cases and inform environmental policy with appropriate biodiversity information in a timely manner. We present the first ever global analysis of extinction risk in reptiles, based on a random representative sample of 1500 species (16% of all currently known species). To our knowledge, our results provide the first analysis of the global conservation status and distribution patterns of reptiles and the threats affecting them, highlighting conservation priorities and knowledge gaps which need to be addressed urgently to ensure the continued survival of the world’s reptiles. Nearly one in five reptilian species are threatened with extinction, with another one in five species classed as Data Deficient. The proportion of threatened reptile species is highest in freshwater environments, tropical regions and on oceanic islands, while data deficiency was highest in tropical areas, such as Central Africa and Southeast Asia, and among fossorial reptiles. Our results emphasise the need for research attention to be focussed on tropical areas which are experiencing the most dramatic rates of habitat loss, on fossorial reptiles for which there is a chronic lack of data, and on certain taxa such as snakes for which extinction risk may currently be underestimated due to lack of population information. Conservation actions specifically need to mitigate the effects of human-induced habitat loss and harvesting, which are the predominant threats to reptiles.
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BACKGROUND: An understanding of the conservation status of Madagascar's endemic reptile species is needed to underpin conservation planning and priority setting in this global biodiversity hotspot, and to complement existing information on the island's mammals, birds and amphibians. We report here on the first systematic assessment of the extinction risk of endemic and native non-marine Malagasy snakes, lizards, turtles and tortoises. METHODOLOGY/PRINCIPAL FINDINGS: Species range maps from The IUCN Red List of Threatened Species were analysed to determine patterns in the distribution of threatened reptile species. These data, in addition to information on threats, were used to identify priority areas and actions for conservation. Thirty-nine percent of the data-sufficient Malagasy reptiles in our analyses are threatened with extinction. Areas in the north, west and south-east were identified as having more threatened species than expected and are therefore conservation priorities. Habitat degradation caused by wood harvesting and non-timber crops was the most pervasive threat. The direct removal of reptiles for international trade and human consumption threatened relatively few species, but were the primary threats for tortoises. Nine threatened reptile species are endemic to recently created protected areas. CONCLUSIONS/SIGNIFICANCE: With a few alarming exceptions, the threatened endemic reptiles of Madagascar occur within the national network of protected areas, including some taxa that are only found in new protected areas. Threats to these species, however, operate inside and outside protected area boundaries. This analysis has identified priority sites for reptile conservation and completes the conservation assessment of terrestrial vertebrates in Madagascar which will facilitate conservation planning, monitoring and wise-decision making. In sharp contrast with the amphibians, there is significant reptile diversity and regional endemism in the southern and western regions of Madagascar and this study highlights the importance of these arid regions to conserving the island's biodiversity.
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Although viviparity is widely considered to evolve irreversibly from oviparity, an analysis of squamates by de Fraipont, Clobert, and Barbault in 1996 presented evidence to the contrary; it also argued that oviparous egg-guarding evolves from viviparity. The response by Shine and Lee in 1999 offers significant criticisms of this analysis and challenges its conclusions. My paper shows that the analysis by de Fraipont et al. exhibits several methodological shortcomings: use of outdated taxonomy and non-monophyletic groups, questionable codification of character states, focus on a very limited data base, analysis of taxonomic categories that are unnecessarily inclusive, and reliance on an invalid correlation between reproductive mode and body size. In comparison to the present analysis (in which 102-115 potential origins of viviparity are defined), de Fraipont et al. have focused on a small number of evolutionary transitions and have generated multiple, conflicting hypotheses about each; the result is highly inflated estimates of heterodox transformations that mainly reflect discrepant phylogenetic interpretations. I therefore support and expand upon Shine and Lee's conclusions. A reversion from viviparity to oviparity cannot be ruled out on theoretical grounds, but evidence for its occurrence among squamates thus far remains exceedingly weak.
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Reproductive mode data were extracted piecemeal from the literature and superimposed over currently accepted phylogenies to permit estimation of the minimum frequencies with which viviparity (live-bearing) has evolved in lizards, aswell as to facilitateanalysisoffactors hypothesizedto inlluencethis evolution. Viviparity has arisen on at least 45 separate occasions in the Sauria. Each ofthese origins is pin-pointed phylogeneticallyas far as is now possible. Ofthese origins, 22 have occurred in the Scincidae, ten in the Iguanidae, five in the Anguidae, two each in the Lacertidae and Gekkonidae, and one each in the Chamaeleontidae, Xantusiidae, Agamidae, and Cordylidae. Further origins may be detected in the Scinci-dae, Iguanidae, and Diploglossa as phylogenetic relationships are elucidated. Over 19 % of the saurian species are live-bearing, and about 2/3 of the viviparous species are skinks. Most of the sub-generic saurian origins ofviviparity have occurred in cold climates, possibly as an adap-tation to facilitate maternal thermoregulation of the developing embryos. Phylogenetic distributions of these origins are consistent with hypotheses that genetic sex-determination of the male-heterogametic type as weil as a tendency towards egg'retention preadapt a lineage for viviparity. Evolution of the live-bearing mode may be constrained by temperature-dependent sex determination, female heterogamety, and formation of highly calcified eggshells.
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The Red List Index uses information from the IUCN Red List to track trends in the projected overall extinction risk of sets of species. It has been widely recognised as an important component of the suite of indicators needed to measure progress towards the international target of significantly reducing the rate of biodiversity loss by 2010. However, further application of the RLI (to non-avian taxa in particular) has revealed some shortcomings in the original formula and approach: It performs inappropriately when a value of zero is reached; RLI values are affected by the frequency of assessments; and newly evaluated species may introduce bias. Here we propose a revision to the formula, and recommend how it should be applied in order to overcome these shortcomings. Two additional advantages of the revisions are that assessment errors are not propagated through time, and the overall level extinction risk can be determined as well as trends in this over time.
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Lizards and snakes (squamate reptiles) are the most diverse vertebrate group in Australia, with approximately 1000 described species, representing about 10% of the global squamate diversity. Squamates are a vital part of the Australian ecosystem, but their conservation has been hindered by a lack of knowledge of their diversity, distribution, biology and key threats. The Action Plan for Australian Lizards and Snakes 2017 provides the first comprehensive assessment of the conservation status of Australian squamates in 25 years. Conservation assessments are provided for 986 species of Australian lizards and snakes (including sea snakes). Over the past 25 years there has been a substantial increase in the number of species and families recognised within Australia. There has also been an increase in the range and magnitude of threatening processes with the potential to impact squamates. This has resulted in an increase in the proportion of the Australian squamate fauna that is considered Threatened. Notably over this period, the first known extinction (post-European settlement) of an Australian reptile species occurred – an indication of the increasingly urgent need for better knowledge and management of this fauna. Six key recommendations are presented to improve the conservation management and plight of Australian squamates. This Action Plan represents an essential resource for research scientists, conservation biologists, conservation managers, environmental consultants, policy makers from Commonwealth and State/Territory governments, and the herpetological community.
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Compared to the global average, extinction risk for mainland African reptiles, particularly for South Africa, appears to be relatively low. Despite this, African reptiles are under threat primarily due to habitat loss as a result of agriculture, resource extraction, and urbanisation, and these pressures are expected to increase into the future. South Africa's reptile fauna is relatively well-studied, allowing an investigation of whether threat status assessment limitations are driving the comparably low threat status for the country, a large component of Africa's reptile fauna (ca. 25% of mainland African reptiles are found in South Africa). Extinction risk of South African reptiles was assessed as of 2018 using IUCN criteria and we ‘backcast’ these assessments to infer extinction risk circa 1990. A Red List Index (RLI: a measure of the extinction risk for a group of species) for 1990 and 2018 was estimated, and the protection level afforded to South African reptiles was investigated by intersecting reptile distributions with the network of protected areas. Finally, a coarse estimate of extinction rate was made. Level of extinction risk for South African reptiles (ca. 5.4%) is lower than the global average, and most currently threatened species would have already been at risk by 1990. The RLI was slightly lower for 2018 than for 1990, and the decrease was more prominent for endemic reptiles than for all reptiles combined. Most South African reptiles fall into the Well Protected category, implying that the protected area network has substantial conservation impact. However, many threatened reptile species are Poorly Protected or Not Protected. The current extent of the protected area network therefore, does not adequately mitigate extinction risk for reptiles. Furthermore, the protected area expansion plan for South Africa would not capture any additional threatened species within its boundaries. Despite the lower level of extinction risk indicated by IUCN assessments, it would be premature to assume that South African reptiles are faring better than reptiles globally based only on this one measure. Notably, two South African reptiles are Critically Endangered and theses are not found in protected areas, two others are already classified as Extinct, and rough estimates of extinction rates are similar to values estimated for other vertebrates. By considering additional metrics that are directly guided by our in-depth knowledge of the species, their distributions and the threats, we demonstrate that South African reptiles are under pressure and that risk of extinction is tangible for several species.
Article
We have no information on the risk of extinction of 21% of reptiles listed as Data Deficient on the Sampled Red List Index (SRLI), an indicator developed to track global change in species status. Data Deficient species are of high research priority, because they contribute to uncertainty in estimates of extinction risk and are neglected by conservation programmes. We review the causes of data deficiency in reptiles; the likely status of Data Deficient reptiles; and possible solutions for their re-assessment. We find that 52% of Data Deficient reptiles lack information on population status and trends, and that few species are only known from type specimens and old records. We build a random forest model for SRLI species of known extinction risk, based on life-history, environmental and threat information. The final model shows perfect classification accuracy (100%) in ten-fold cross validation. We use the model to predict that 56 of 292 Data Deficient reptiles (19%) are at risk of extinction, so the overall proportion of threatened reptiles in the SRLI (19%) remains unchanged. Regions predicted to contain large numbers of threatened Data Deficient reptiles overlap with known centres of threatened species richness. However, the model shows lower accuracy (79%) on 29 species recently re-assessed in the Global Reptile Assessment. Predictive models could be used to prioritize Data Deficient species and reptiles not included in the SRLI, and new reptile assessments could be used to improve model predictions through adaptive learning.
Article
The pace of new reptile species descriptions, especially of new lizard descriptions, is rapidly increasing. The number of recognized lizard species has increased by more than 30% since the turn of the century. I examined the traits of newly described lizard taxa, and compared them to those of species described earlier, to predict where new species will be found, what traits they have, and whether they are likely to be more extinction-prone than well-known species. I compiled data on the biogeography and ecology of newly described forms and examined the relationship between these traits and the date of description. As expected, new descriptions are generally of small species, predominantly with small geographic ranges. Most species have been described from the Oriental Realm, whereas few new species were described from Africa. New descriptions are disproportionally biased in favor of geckos and of nocturnal species - and, surprisingly, contain few subterranean forms. Newly described lizard species are more likely to be threatened with extinction and may be more susceptible to population decline. Although the rate of new lizard descriptions is still accelerating, this work contributes to predicting what types of species are likely to be found in the future - and where. The small ranges of such species, in regions suffering from severe habitat degradation, suggests that strong mitigation measures are needed to ensure that many of these species will not be lost shortly after being described.
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Effective and targeted conservation action requires detailed information about species, their distribution, systematics and ecology as well as the distribution of threat processes which affect them. Knowledge of reptilian diversity remains surprisingly disparate, and innovative means of gaining rapid insight into the status of reptiles are needed in order to highlight urgent conservation cases and inform environmental policy with appropriate biodiversity information in a timely manner. We present the first ever global analysis of extinction risk in reptiles, based on a random representative sample of 1500 species (16% of all currently known species). To our knowledge, our results provide the first analysis of the global conservation status and distribution patterns of reptiles and the threats affecting them, highlighting conservation priorities and knowledge gaps which need to be addressed urgently to ensure the continued survival of the world’s reptiles. Nearly one in five reptilian species are threatened with extinction, with another one in five species classed as Data Deficient. The proportion of threatened reptile species is highest in freshwater environments, tropical regions and on oceanic islands, while data deficiency was highest in tropical areas, such as Central Africa and Southeast Asia, and among fossorial reptiles. Our results emphasise the need for research attention to be focussed on tropical areas which are experiencing the most dramatic rates of habitat loss, on fossorial reptiles for which there is a chronic lack of data, and on certain taxa such as snakes for which extinction risk may currently be underestimated due to lack of population information. Conservation actions specifically need to mitigate the effects of human-induced habitat loss and harvesting, which are the predominant threats to reptiles.
Article
An attempt is made to identify all squamate lineages having undergone limb reduction in the sense of having lost one or more bones from either the front or rear limb. The limb osteology of the ancestors of these limb reduced lineages is also inferred. On this basis squamates have undergone limb reduction at least 62 times in 53 lineages. Most reductions begin with the loss of a single phalange; however, some may begin with loss of all elements more distal than the mesopodials. Three different patterns of incipient loss occur in the front limb and two in the rear limb. These trends are discussed in the light of the "developmental constraint" and "adaptation" hypotheses.
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Skinks are usually grouped in a single family, Scincidae (1,579 species) representing one-quarter of all lizard species. Other large lizard families, such as Gekkonidae (s.l.) and Iguanidae (s.l.), have been partitioned into multiple families in recent years, based mainly on evidence from molecular phylogenies. Subfamilies and informal suprageneric groups have been used for skinks, defined by morphological traits and supported increasingly by molecular phylogenies. Recently, a seven-family classification for skinks was proposed to replace that largely informal classification, create more manageable taxa, and faciliate systematic research on skinks. Those families are Acontidae (26 sp.), Egerniidae (58 sp.), Eugongylidae (418 sp.), Lygosomidae (52 sp.), Mabuyidae (190 sp.), Sphenomorphidae (546 sp.), and Scincidae (273 sp.). Representatives of 125 (84%) of the 154 genera of skinks are available in the public sequence databases and have been placed in molecular phylogenies that support the recognition of these families. However, two other molecular clades with species that have long been considered distinctive morphologically belong to two new families described here, Ristellidae fam. nov. (14 sp.) and Ateuchosauridae fam. nov. (2 sp.). Morphological diagnoses and species content for all nine families of skinks (Scincomorpha) are presented.
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Effective biodiversity monitoring is critical to evaluate, learn from, and ultimately improve conservation practice. Well conceived, designed and implemented monitoring of biodiversity should: (i) deliver information on trends in key aspects of biodiversity (e.g. population changes); (ii) provide early warning of problems that might otherwise be difficult or expensive to reverse; (iii) generate quantifiable evidence of conservation successes (e.g. species recovery following management) and conservation failures; (iv) highlight ways to make management more effective; and (v) provide information on return on conservation investment. The importance of effective biodiversity monitoring is widely recognized (e.g. Australian Biodiversity Strategy). Yet, while everyone thinks biodiversity monitoring is a good idea, this has not translated into a culture of sound biodiversity monitoring, or widespread use of monitoring data. We identify four barriers to more effective biodiversity monitoring in Australia. These are: (i) many conservation programmes have poorly articulated or vague objectives against which it is difficult to measure progress contributing to design and implementation problems; (ii) the case for long-term and sustained biodiversity monitoring is often poorly developed and/or articulated; (iii) there is often a lack of appropriate institutional support, co-ordination, and targeted funding for biodiversity monitoring; and (iv) there is often a lack of appropriate standards to guide monitoring activities and make data available from these programmes. To deal with these issues, we suggest that policy makers, resource managers and scientists better and more explicitly articulate the objectives of biodiversity monitoring and better demonstrate the case for greater investments in biodiversitymonitoring. There is an urgent need for improved institutional support for biodiversity monitoring in Australia, for improved monitoring standards, and for improved archiving of, and access to, monitoring data. We suggest that more strategic financial, institutional and intellectual investments in monitoring will lead to more efficient use of the resources available for biodiversity conservation and ultimately better conservation outcomes.
Article
Squamate reptiles generally have been ignored in the search for a unified theory for the evolution of sociality due to the perception that they exhibit little social behavior beyond territoriality and dominance hierarchies and display polygynous mating systems. However a growing body of research has revealed unsuspected levels of social complexity and diversity in mating systems within the squamate lineage, particularly among the members of the Australian Scincid genus Egernia. Several species of Egernia are amongst the most highly social of all squamate reptiles, exhibiting stable social aggregations and high levels of long-term social and genetic monogamy. Social complexity is widespread within the Egernia genus, with reports of social aggregations in 23 of the 30 described species. The purpose of this review was to examine the potential for the Egernia genus as a model system for study of the evolution of sociality and monogamy within squamate reptiles. Current evidence indicates there is substantial variability in social complexity both within and between species, with social organization covering the spectrum from solitary to highly social. Four highly social Egernia species are known to live in stable social aggregations consisting of closely related individuals (adults, subadults, juveniles; i.e., 'family' groups) that appear to utilize chemical cues to recognize group members (kin recognition). Enhanced vigilance against predators is one presumed benefit of group membership. Additionally, juveniles within social groupings appear to receive low levels of indirect parental care. Several Egernia species create scat piles that mark group territories. Three Egernia species exhibit long-term social and genetic monogamy and several inbreeding avoidance strategies have been documented. However, it is currently unknown whether monogamy is widespread within Egernia. Egernia species occupy a broad range of habitats, although most are terrestrial, saxicolous or semi-arboreal. Several species display an attachment to a permanent home site, generally a rock crevice, burrow or tree hollow. Egernia species take 2–5 years to mature, live for 5–25 years, and are viviparous with litter size positively correlated with body size. Several Egernia species are herbivorous, with the degree of herbivory increasing with body size and during ontogeny in larger species. Most smaller species are either insectivorous or omnivorous. Species of Egernia have a wide range of reptilian, avian, and mammalian predators. Several larger species possess several behavioral and morphological features to prevent their extraction from rock crevices, including highly modified keeled scales and numerous defensive behaviors. Color pattern polymorphism is present in five Egernia species. Potential ecological correlates of sociality and monogamy are discussed. The life-history hypothesis predicts long-lived, late-maturing species should evolve complex sociality. The habitat availability hypothesis relies on the assumption that refugia may be limited in some ecological settings, and group formation is a consequence of co-habitation of available refugia. These hypotheses are not mutually exclusive, and testable predictions are formulated and discussed. Specific future research directions are outlined to take advantage of Egernia as a model system for comparative research on a lineage that represents an independent origin of social organization comparable to that found in birds and mammals. THE Australian Scincid genus Egernia com-prises some of Australia's largest, more ubiq-uitous and easily identifiable lizards (Cogger, 2000; Greer, 1989). Several species of Egernia are among the most highly social of all squamate reptiles, and recent research has suggested that studies focused on this genus could provide a valuable contribution to our understanding of the evolution of complex sociality and monogamous mating systems in reptiles. Complex sociality appears to be widespread within the Egernia lineage, with anecdotal reports of social aggregations docu-mented for 23 of the 30 currently recognised species. The size, complexity, and stability of these aggregations appear to vary noticeably both among species, and among populations of the same species, indicating diversity of social organization within the genus.
Article
Species range maps based on extents of occurrence (EOO maps) have become the basis for many analyses in broad-scale ecology and conservation. Nevertheless, EOO maps are usually highly interpolated and overestimate small-scale occurrence, which may bias research outcomes. We evaluated geographical range overestimation and its potential ecological causes for 1158 bird species by quantifying EOO map occurrence across 4040 well-studied survey locations in Australia, North America, and southern Africa at the scale of 80-742 km2. Most species occurred in only 40-70% of the range indicated by their EOO maps. The observed proportional range overestimation affected the range-size frequency distribution, indicating that species are more range-restricted than suggested by EOO maps. The EOO maps most strongly overestimated the distribution of narrow-ranging species and ecological specialists with narrow diet and habitat breadth. These relationships support basic ecological predictions about the relationship between niche breadth and the fine-scale occurrence of species. Consequently, at-risk species were subject to particularly high proportional range overestimation, on average 62% compared with 37% of nonthreatened species. These trends affect broad-scale ecological analyses and species conservation assessments, which will benefit from a careful consideration of potential biases introduced by range overestimation.
The biology and evolution of scincid lizards
  • A E Greer
Greer, A.E., 2007. The biology and evolution of scincid lizards. Available from. htt ps://www.academia.edu/35305801/The_Biology_and_Evolution_of_Scincid_Lizards. doc.
The IUCN Red List of Threatened Species. Version 2020-1
  • Iucn
IUCN, 2020. The IUCN Red List of Threatened Species. Version 2020-1. https://www. iucnredlist.org.
Traits of lizards of the world: variations around a successful evolutionary design
  • Meiri
Meiri, S., 2018. Traits of lizards of the world: variations around a successful evolutionary design. Glob. Ecol. Biogeogr. 27, 1168-1172.
Essential of Conservation Biology
  • R B Primack
Primack, R.B., 2014. Essential of Conservation Biology, Sixth edition. Sinauer Associates, Sunderland Massachusetts, USA.
The extent and adequacy of monitoring for Australian threatened reptile species
  • Woinarski
Woinarski, J.C.Z., 2018. The extent and adequacy of monitoring for Australian threatened reptile species. In: Legge, S., Lindenmayer, D.B., Robinson, N.M., Scheele, B.C., Southwell, D.M., Wintle, B.A. (Eds.), Monitoring Threatened Species and Ecological Communities. CSIRO Publishing, Clayton, pp. 69-84.
Stable social grouping in lizards. Chapter 10
  • While