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1.
BMC Vet Res ; 18(1): 205, 2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35624481

RESUMO

BACKGROUND: Gut and oral microbes form complex communities and play key roles in co-evolution with their hosts. However, little is understood about the bacterial community in lizards. RESULTS: In this study, we investigated the gut and oral bacterial communities in Japalura sensu lato from Sichuan Province, China, using 16S rRNA gene sequencing. Results showed that Bacteroidota (36.5%) and Firmicutes (32.8%) were the main phyla in the gut, while Proteobacteria, Bacteroidota, Firmicutes, and Actinobacteriota were the dominant phyla in the oral cavity. 16 S rRNA sequencing analysis of fecal samples showed that: (1) Bacteroidota was the most abundant in Japalura sensu lato, which was different from the bacterial community of insectivorous animals; (2) Bacteroidota, Firmicutes, Actinobacteriota, Fusobacteriota, and Cyanobacteria were the most abundant phylum in Japalura sensu lato. (3) Proteobacteria was the dominant phylum in Japalura sensu lato and other domestic insectivorous lizards (Shinisaurus crocodilurus, Phrynocephalus vlangalii, and Takydromus septentrionalis); (4) Comparing with the bacterial community of Shinisaurus crocodilurus, Phrynocephalus vlangalii, Takydromus septentrionalis, Liolaemus parvus, L. ruibali, and Phymaturus williamsi, Desulfobacterota was uniquely present in the gut of Japalura sensu lato. 16 S rRNA sequencing of oral samples showed that Chloroflexi and Deinococcota phyla were enriched in the oral cavity, which may have a significant influence on living in extreme environments. CONCLUSIONS: Thus, based on 16 S rRNA sequencing analysis of the community composition of the gut and oral microbiomes, this study firstly represents a foundation for understanding the gut and oral microbial ecology of Japalura sensu lato, and constitutes a detail account of the diversity of the microbiota inhabiting the gut and oral cavity of Japalura sensu lato. Further researches will continue to reveal how gut and oral microbial communities may be impacting the ecology and evolution of lizards.


Assuntos
Lagartos , Microbiota , Animais , Bactérias/genética , Bacteroidetes/genética , Fezes/microbiologia , Firmicutes/genética , RNA Ribossômico 16S/genética
2.
BMC Genet ; 18(1): 62, 2017 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-28673260

RESUMO

BACKGROUND: Genome-wide investigation of molecular mechanisms for high-altitude adaptation has attracted great attention in the last few years. In order to understand the contribution of gene expression level variations to high-altitude adaptation in Asiatic toads (Bufo gargarizans), we implemented a reciprocal transplant experiment between low- and high-altitude sites and sequenced 12 transcriptomes from brain, heart, and liver tissues. RESULTS: A large number of genes with expression differences (DEGs) between high- and low-altitude individuals (193 fixed and 844 plastic) were identified, and the majority of them were tissue specific. Heart displayed the largest number of DEGs, both plastic and fixed. Fixed DEGs were particularly concentrated in functions associated with muscle contraction, and the majority of them were down-regulated in high-altitude individuals. Plastic DEGs were highly concentrated in several energy metabolism related functional categories, and the majority of them were also down-regulated at high-altitude environments. In liver samples, genes associated with nutrient metabolism experienced a broad-scale expression down-regulation in high-altitude toads. CONCLUSIONS: These broadly suppressed expression patterns at high altitudes are in strong contrast to those of endothermic homeotherms, suggesting poikilothermic vertebrates may have adopted different strategies at high altitudes. Our results strongly support that both genotypic specialization and phenotypic plasticity play crucial role in adaptation to high altitude for Asiatic toads. Poikilothermic vertebrates are among the most hypoxia-tolerant animals known, and many molecular mechanisms remain elusive. We hope that our results will provide useful directions for future research.


Assuntos
Aclimatação , Bufonidae/genética , Regulação da Expressão Gênica , Variação Genética , Altitude , Animais , Encéfalo/metabolismo , Bufonidae/fisiologia , Coração/fisiologia , Fígado/metabolismo
3.
Zookeys ; 1200: 65-74, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38751966

RESUMO

Lycodongammiei (Blanford, 1878), a rarely encountered species of Asian snake, is characterized by ambiguous systematics and biology. Based on a sole specimen of L.gammiei rediscovered in southeastern Xizang, China, we conduct a detailed morphological examination and description, and investigate the systematic position of this species. Morphologically, the newly collected specimen is closely aligned with specimens previously described. Mitochondrial DNA-based phylogenetic analyses reveal that L.gammiei constitutes an independent evolutionary lineage, forming a clade with L.fasciatus (Anderson, 1879), L.gongshan Vogel & Luo, 2011, L.butleri Boulenger, 1900, and L.cavernicolus Grismer, Quah, Anuar, Muin, Wood & Nor, 2014. The closest genetic distance between L.gammiei and its congeners was 10.2%. The discovery of L.gammiei in Medog County, China, signifies an eastward expansion of its known geographical distribution.

4.
Ecol Evol ; 14(5): e11445, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38779528

RESUMO

Habitat is fundamental for facilitating various life activities in animals, for instance, snakes procure essential energy for survival and reproduction by selecting ambush microhabitats. While there has been extensive research on the selection of microhabitat for feeding in terrestrial and aquatic snakes, little is known about arboreal snakes. In the present study, we analyzed the ambush microhabitat preferences of Viridovipera stejnegeri, a widely distributed Asian pitviper in China, conducted association analysis between snake microhabitat and prey microhabitat and abundance to determine the ro5le of microhabitat selection in feeding. Employing random forest analysis and habitat selection functions, we further constructed a predictive framework for assessing the probability of ambush site selection by V. stejnegeri. Our results revealed that V. stejnegeri exhibited a distinct microhabitat preference for ambush prey. Among the 13 environmental factors assessed, V. stejnegeri showed pronounced preferences towards 12 of these factors, including climatic factors, geographical factors, and vegetation factors. Furthermore, although the preferences of V. stejnegeri overlapped substantially with those of its prey across multiple habitat factors, food abundance shows no significant association with various habitat factors of V. stejnegeri, and does not have significant predictive effect on habitat selection of V. stejnegeri. Therefore, we infer that V. stejnegeri does not preferentially select microhabitats with the highest food abundance, which does not support the hypothesis that "snakes select habitats based on the spatial distribution of prey abundance." By analyzing the characteristics of vegetation, geography, and climate, we conclude that V. stejnegeri tends to choose microhabitats with better ambush conditions to increase attack success rate, thereby achieving the optimal feeding success rate at the microhabitat scale, which is in line with the predictions of optimal foraging theory. This study provides new insights into the predation ecology and habitat selection of snakes.

5.
Ecol Evol ; 14(4): e11278, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38628918

RESUMO

Although several phylogeographic studies of Asian snakes have been conducted, most have focused on pitvipers, with non-venomous snakes, such as colubrids or natricids, remaining poorly studied. The Chinese keelback water snake (Trimerodytes percarinatus Boulenger) is a widespread, semiaquatic, non-venomous species occurring in China and southeastern Asia. Based on mitochondrial DNA (mtDNA) and single nucleotide polymorphism (SNP) data, we explored the population genetic structure, genetic diversity, and evolutionary history of this species. MtDNA-based phylogenetic analysis showed that T. percarinatus was composed of five highly supported and geographically structured lineages. SNP-based phylogenetic analysis, principal component analysis, and population structure analysis consistently revealed four distinct, geographically non-overlapping lineages, which was different from the mtDNA-based analysis in topology. Estimation of divergence dates and ancestral area of origin suggest that T. percarinatus originated ~12.68 million years ago (95% highest posterior density: 10.36-15.96 Mya) in a region covering southwestern China and Vietnam. Intraspecific divergence may have been triggered by the Qinghai-Xizang Plateau uplift. Population demographics and ecological niche modeling indicated that the effective population size fluctuated during 0.5 Mya and 0.002 Mya. Based on the data collected here, we also comment on the intraspecific taxonomy of T. percarinatus and question the validity of the subspecies T. p. suriki.

6.
Zookeys ; 1182: 307-329, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37900706

RESUMO

A new species of Xenophrys is described from Yadong County, Tibet Autonomous Region, China based on morphological and molecular evidence. Phylogenetic analyses based on the mitochondrial genes 16S rRNA and COI indicated that this new species represents an independent lineage and the minimum p-distance based on 16S rRNA between this species and its congeners is 4.4%. Additionally, the new species is distinguished from its congeners by a combination of the following morphological characters: (1) small body size, SVL 17.9-22.2 mm in adult males and SVL 23.4 mm in the single adult female; (2) tympanum indistinct, supratympanic fold distinct; (3) canthus rostralis well-developed, snout tip far beyond the margin of the lower lip; (5) pupil vertical; (6) vomerine teeth present, maxillary teeth present; (7) tongue notched posteriorly; (8) supernumerary tubercles absent, subarticular, metacarpal and metatarsal tubercles indistinct; (9) relative finger lengths I < II < IV < III, finger tips rounded, slightly expanded relative to digit widths; (10) toes with narrow lateral fringes and tarsal folds; (11) a dark triangular marking with light edge between eyes, a dark ")("-shaped marking, with light edge, present on center of dorsum, pectoral glands on sides of the breast.

7.
Ecol Evol ; 13(8): e10367, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37529581

RESUMO

The elucidation of species diversity and distribution is critical within the fields of evolution, genetics, and conservation. The genus Sibynophis contains rare snakes that have historically received little attention. In this study, we conducted comprehensive sampling and use both mitochondrial and nuclear genetic markers to explore Sibynophis species diversity within China. Our findings revealed that S. c. miyiensis should be considered synonymous with S. c. grahami, and S. c. grahami should be gave a specific rank as S. grahami. In addition, we discovered S. triangularis was new to China and Myanmar. Based on the specimens and molecular phylogeny results, we redefined the species distribution boundaries of each Chinese species.

8.
Mol Ecol Resour ; 23(5): 1124-1141, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36924341

RESUMO

DNA barcoding has greatly facilitated studies of taxonomy, biodiversity, biological conservation, and ecology. Here, we establish a reliable DNA barcoding library for Chinese snakes, unveiling hidden diversity with implications for taxonomy, and provide a standardized tool for conservation management. Our comprehensive study includes 1638 cytochrome c oxidase subunit I (COI) sequences from Chinese snakes that correspond to 17 families, 65 genera, 228 named species (80.6% of named species) and 36 candidate species. A barcode gap analysis reveals gaps, where all nearest neighbour distances exceed maximum intraspecific distances, in 217 named species and all candidate species. Three species-delimitation methods (ABGD, sGMYC, and sPTP) recover 320 operational taxonomic units (OTUs), of which 192 OTUs correspond to named and candidate species. Twenty-eight other named species share OTUs, such as Azemiops feae and A. kharini, Gloydius halys, G. shedaoensis, and G. intermedius, and Bungarus multicinctus and B. candidus, representing inconsistencies most probably caused by imperfect taxonomy, recent and rapid speciation, weak taxonomic signal, introgressive hybridization, and/or inadequate phylogenetic signal. In contrast, 43 species and candidate species assign to two or more OTUs due to having large intraspecific distances. If most OTUs detected in this study reflect valid species, including the 36 candidate species, then 30% more species would exist than are currently recognized. Several OTU divergences associate with known biogeographic barriers, such as the Taiwan Strait. In addition to facilitating future studies, this reliable and relatively comprehensive reference database will play an important role in the future monitoring, conservation, and management of Chinese snakes.


Assuntos
Biodiversidade , Código de Barras de DNA Taxonômico , Humanos , Animais , Filogenia , Código de Barras de DNA Taxonômico/métodos , Serpentes/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética
9.
Ecol Evol ; 12(3): e8652, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35261743

RESUMO

Dispersal plays a vital role in the geographical distribution, population genetic structure, quantity dynamics, and evolution of a species. Sex-biased dispersal is common among vertebrates and many studies have documented a tendency toward male-biased dispersal in mammals and female-biased dispersal in birds. However, dispersal patterns in reptiles remain poorly understood. In this study, we explored the genetic diversity and dispersal patterns of the widely distributed Asian pitviper Protobothrops mucrosquamatus. In total, 16 polymorphic microsatellite loci were screened in 150 snakes (48 males, 44 females, 58 samples without sex information) covering most of their distribution. Microsatellite analysis revealed high genetic diversity in P. mucrosquamatus. Bayesian clustering of population assignment identified two major clusters for all populations, somewhat inconsistent with the mitochondrial DNA phylogeny of P. mucrosquamatus reported in previous research. Analyses based on 92 sex-determined and 37 samples of P. mucrosquamatus from three small sites in Sichuan, China (Mingshan, Yibin, and Zizhong) consistently suggested female-biased dispersal in P. mucrosquamatus, which is the first example of this pattern in snakes. The female-biased dispersal patterns in P. mucrosquamatus may be explained by local resource competition.

10.
Curr Zool ; 68(5): 526-534, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36324530

RESUMO

Island species and their ecosystems play an important role in global biodiversity preservation, and many vulnerable island species are conservation priorities. Although insular habitat likely facilitates the species diversification process, it may also aggravate the fragility of these species with high risk of inbreeding. The Shedao pit-viper Gloydius shedaoensis is an island endemic species with an extremely high population density, which has been categorized as vulnerable in the IUCN (International Union for the Conservation of Nature and Natural Resources) Red List. We collected 13,148 SNP (Single Nucleotide Polymorphism) from across its genome and examined its genetic diversity and demographic history. The Shedao pit-viper has a low genetic diversity but shows no sign of inbreeding. Furthermore, population genetic structure analysis, including the neighbor-joining tree, principal coordinate analysis, clustering, and spatial autocorrelation, revealed a general lack of spatial structure. Only the isolation by distance residues suggested a weak patchiness. Overall, the population is nearly panmictic and gene flow is evenly distributed across the island. A large number of individuals, small size of the island, and the lack of population structure likely all contribute to the lack of inbreeding in this species. We also detected signs of male-biased dispersal, which likely is another inbreeding avoidance strategy. Historical demographic analysis suggested that the historical population size and distribution of the species are much larger than their current ones. The multiple transgressive-regressive events since the Late Pleistocene are likely the main cause of the population size changes. Taken together, our results provide a basic scientific foundation for the conservation of this interesting and important species.

11.
Zootaxa ; 5213(2): 159-168, 2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-37044945

RESUMO

Lycodon is a species-rich genus that currently contains 72 named species. Lycodon zayuensis Jiang, Wang, Jin & Che, 2020, was described from Lower Chayu Town, Chayu County, Tibet, China, based on a single female holotype. During our recent field work, three additional specimens, including two females and one male, were collected and identified as L. zayuensis based on morphological comparison and the cytochrome b mitochondrial gene (1049 bp). Here, we provide an expanded description of this recently described species based on all known specimens.


Assuntos
Colubridae , Masculino , Feminino , Animais , Citocromos b/genética , Filogenia
12.
Zootaxa ; 5195(2): 125-142, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37045302

RESUMO

Based on molecular evidence and morphological data, we describe a new species Raorchestes yadongensis sp. nov. from Yadong County, Xizang Autonomous Region, China. The new species can be distinguished based on a combination of the following characters: (1) small body size, SVL 17.8-24.1 mm in adult males; (2) head wider than long; (3) eye diameter about three times as much as tympanum diameter; (4) tympanum distinct; (5) fingers with rudimentary webbing and narrow lateral dermal fringes; relative finger lengths I < II < IV < III; number of subarticular tubercles in fingers 1, 1, 2, 1; (6) toes with rudimentary webbing and narrow lateral dermal fringes; relative toe lengths I < II < III < V < IV; number of subarticular tubercles in toes 1, 1, 2, 3, 2; inner metatarsal tubercle distinct, outer metatarsal tubercle absent; (7) tips of fingers and toes present discs, and discs pale brown or yellow in life; (8) tibiotarsal articulation reaching the tip of snout when adpressed; (9) milky nuptial pad present on the dorsal surface of first finger; (10) dorsal surface light brown with white warts, ventral surface with irregular white patches. The new species is currently known in Yadong County, Xizang, China, but may also occur in neighboring Bhutan and India. A key to Chinese species of the genus Raorchestes is also provided.


Assuntos
Anuros , Masculino , Animais , Filogenia , China , Tamanho Corporal
13.
Mitochondrial DNA B Resour ; 6(10): 3041-3043, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34595335

RESUMO

The mountain dragon, Diploderma vela, is an endemic and protected valley lizard that inhabits the upper Lantsang Valley in West China. In this study, we sequenced the complete mitochondrial genome of a male individuals of D. vela using next-generation sequencing methodologies. The complete mitogenome is 16,432 bp in length and contains one noncoding control regions, 13 protein-coding, 22 transfer RNA and two ribosomal RNA genes. The mitogenome content and structure of D. vela was consistent with the previously published representatives of the family. A Bayesian phylogenetic analysis using the complete mitochondrial genomes of Agamidae fully resolved D. vela in the Draconinae, a result consistent with previous investigations. This study provides bioinformatic data for better understanding the evolution and the phylogenetic history of the mountain dragon.

14.
Zootaxa ; 5026(2): 239-254, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34810931

RESUMO

A new species of the xenodermid snake genus Achalinus Peters, 1869 is described from Fujian Province, China, based on six specimens. Bayesian inference and maximum likelihood analyses based on a mitochondrial DNA fragment (CO1) indicated the new taxon is different from its congeners (pdistance ≥ 18.5%). Morphologically, the new species can be diagnosed from the other species by a combination of following characters: (1) dorsal scales 23 rows throughout, strongly keeled, the most outer rows on both sides also keeled and slightly enlarged; (2) tail relatively longer, TaL/TL ratio 0.260.29 in males, 0.210.22 in females; (3) maxillary teeth 3033; (4) length of suture between internasals significantly longer than that between prefrontals; (5) nasal divided into two sections by nasal cleft; (6) a single loreal; (7) SPO 1, seldom 2; (8) SPL 6, the fourth and fifth contacting eye; (9) IFL5, rarely 6, the first three touching the first pair of chin shields; (10) TMP 79, arranged in three rows; (11) VS 142149 in males, VS 152154 in females; (12) SC 7481 in males, SC 6365 in females, arranged in a single row; (13) cloacal entire; (14) greyish brown above, pale yellow beneath; (15) dorsum with an indistinct longitudinal vertebral stripe. The description of the new species brings the total species of Achalinus to 19.


Assuntos
Lagartos , Serpentes , Distribuição Animal , Estruturas Animais , Animais , Teorema de Bayes , China , Feminino , Masculino , Filogenia
15.
Mitochondrial DNA B Resour ; 5(3): 3276-3277, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33458138

RESUMO

Asian pitviper Gloydius changdaoensis is a coastal species, distributed in Shandong province, China. In this study, we successfully sequenced the mitochondrial genome of one individual of G. changdaoensis. The complete mitochondrial genome is circular molecular with 17,224 bp, containing an origin of light-strand replication (OL), two non-coding control regions (CRs), and 37 classical genes of vertebrate, which contain 13 protein-coding genes (PCGs), 2 ribosomal RNA genes, and 22 transfer RNA genes. A Bayesian phylogenetic tree using the complete mitochondrial genomes of all viper species available showed a consistent result with previous studies.

16.
G3 (Bethesda) ; 10(5): 1639-1646, 2020 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-32184370

RESUMO

The Shedao pit-viper (Gloydius shedaoensis) exhibits an extreme sedentary lifestyle. The island species exclusively feeds on migratory birds during migratory seasons and experiences prolonged hibernation and aestivation period each year (up to eight months). The sedentary strategy reduces energy expenditure, but may trigger a series of adverse effects and the snakes have likely evolved genetic modifications to alleviate these effects. To investigate the genetic adaptations, we sequenced and compared the transcriptomes of the Shedao pit-viper and its closest mainland relative, the black eyebrow pit-viper (G. intermedius). The Shedao pit-viper revealed a low rate of molecular evolution compared to its mainland relative, which is possibly associated with metabolic suppression. Signals of positive selection were detected in two genes related to antithrombin (SERPINC1) and muscle atrophy (AARS). Those genes exert significant functions in thrombosis, inhibiting oxidation and prolonged fasting. Convergent and parallel substitutions of amino acid with two other sedentary vertebrates, which often suggest adaptation, were found in a fatty acid beta-oxidation related gene (ACATA1) and a circadian link gene (KLF10), which regulate lipogenesis, gluconeogenesis, and glycolysis. Furthermore, a circadian clock gene (CRY2) exhibited two amino acid substitutions specific to the Shedao pit-viper and one variant was predicted to affect protein function. Modifications of these genes and their related functions may have contributed to the survival of this island snake species with a sedentary lifestyle and extreme seasonal food availability. Our study demonstrated several important clues for future research on physiological and other phenotypic adaptation.


Assuntos
Venenos de Crotalídeos , Crotalinae , Animais , Evolução Molecular , Estações do Ano , Serpentes
17.
Zootaxa ; 4860(1): zootaxa.4860.1.6, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33056175

RESUMO

A new species of the xenodermatid snake genus Achalinus Peters, 1869 is described from Yunnan Province, Southwest China, based on a single male specimen. The new species is assigned to the genus Achalinus on the basis of absence of preocular and postocular, subcaudals arranged in single row, and results of phylogenetic analyses of mitochondrial DNA CO1 sequence data. Achalinus pingbianensis sp. nov. differs from its congeners by the combination of following morphological characters: absence of a loreal, internasals subequal to that between prefrontals and dorsal scales strongly keeled, 23 rows throughout. Currently, 13 species are in the genus Achalinus, further taxonomical and phylogenetic studies based on more extensive samples and more markers will help understand the cryptic diversity and clarify their interspecific relationships.


Assuntos
Serpentes , Distribuição Animal , Estruturas Animais , Animais , China , Masculino , Filogenia
18.
PeerJ ; 7: e7205, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31293835

RESUMO

Ecological factors related to predation risks and foraging play major roles in determining which behavioral traits may mediate life history trade-offs and, therefore, the pace-of-life syndrome (POLS) structure among behavioral, physiological, and life-history traits. It has been proposed that activity/exploration or risk-taking behaviors are more likely to impact resource acquisition for organisms (individuals, populations, and species) foraging on clumped and ephemeral food sources than for organisms foraging on abundant and evenly distributed resources. In contrast, vigilance or freezing behavior would be expected to covary with the pace of life when organisms rely on food items requiring long bouts of handling. Nevertheless, it remains unclear how general this pattern is. We tested this hypothesis by examining the associations between exploration/risk-taking behaviors and metabolic/performance traits for the viviparous agamid lizard, Phrynocephalus vlangalii. This species forages on sparse and patchy food sources. The results showed positive correlations between exploration and endurance capacity, and between bite force and risk-taking willingness. Our current findings, in conjunction with our previous work showed no correlations between freezing behavior and performance in this species, support the idea that behaviors in life-history trade-offs are natural history-dependent in P. vlangalii, and provide evidence that behavioral types play functional roles in life history trade-offs to supporting POLS hypothesis.

19.
Integr Zool ; 13(4): 450-470, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29436768

RESUMO

Determining the susceptibility of species to changing thermal niches is a major goal for biologists. In this paper we develop an eco-physiological model of extinction risk under climate change premised on behavioral thermoregulation. Our method downscales operative environmental temperatures, which restrict hours of activity of lizards, hr , for present-day climate (1975) and future climate scenarios (2070). We apply our model using occurrence records of 20 Phrynocephalus lizards (or taxa in species complexes) drawn from literature and museum records. Our analysis is phylogenetically informed, because some clades may be more sensitive to rising temperatures. The limits for computed hr predict local extirpations among Phrynocephalus lizards at continental scales and delineate upper boundaries of thermal niches as defined by Extreme Value Distributions. Under the 8.5 Representative Concentration Pathway scenario, we predict extirpation of 64% of local populations by 2070 across 20 Phrynocephalus species, and 12 are at high risk of total extinction due to thermal limits being exceeded. In tandem with global strategies of lower CO2 emissions, we propose regional strategies for establishing new national parks to protect extinction-prone taxa by preserving high-elevation climate refugia within existing sites of species occurrence. We propose that evolved acclimatization - maternal plasticity - may ameliorate risk, but is poorly studied. Previous studies revealed that adaptive maternal plasticity by thermoregulating gravid females alter progeny thermal preferences by ±1 °C. We describe plasticity studies for extinction-prone species that could assess whether they might be buffered from climate warming - a self-rescue. We discuss an epigenetic framework for studying such maternal-effect evolution.


Assuntos
Extinção Biológica , Lagartos/fisiologia , Temperatura , Aclimatação , Altitude , Animais , Regulação da Temperatura Corporal , Mudança Climática , Feminino , Geografia , Masculino , Óvulo , Filogenia
20.
Sci Rep ; 6: 31573, 2016 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-27526625

RESUMO

Competition between animals for limited resources often involves signaling to establish ownership or dominance. In some species, the defended resource relates to suitable thermal conditions and refuge from predators. This is particularly true of burrow-dwelling lizards such as the Qinghai toad-headed agama (Phrynocephalus vlangalii), which are found on the Tibetan plateau of western China. Male and female lizards occupy separate burrows, which are vital for anti-predator behaviour during warmer months when lizards are active and, crucially, provide shelter from harsh winter conditions. These lizards are readily observed signaling by means of tail displays on the sand dunes they inhabit. Given the selective pressure to hold such a resource, both males and females should exhibit territorial behaviour and we considered this study system to examine in detail how social context influences motion based territorial signaling. We confirmed that territorial signaling was used by both sexes, and by adopting a novel strategy that permitted 3D reconstruction of tail displays, we identified significant variation due to social context. However, signal structure was not related to lizard morphology. Clearly, the burrow is a highly valued resource and we suggest that additional variation in signaling behaviour might be mediated by resource quality.


Assuntos
Comportamento Animal , Lagartos/fisiologia , Cauda/fisiologia , Animais , China , Feminino , Masculino , Estações do Ano , Territorialidade
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