Genetic and morphological divergence among three closely related Phrynocephalus species (Agamidae)
Genetic and morphological divergence among three closely related Phrynocephalus species (Agamidae)
复制标题
三个密切相关的沙蜥属物种（蜥蜴科）之间的遗传和形态差异
DOI：
10.1186/s12862-019-1443-y
复制
发表时间：
2019-06-06
影响因子：
3.4
通讯作者：
Ji, Xiang
中科院分区：
文献类型：
--
作者：
Hu, Chao-Chao;Wu, Yan-Qing;Ji, Xiang
研究背景青藏高原是世界上海拔最高、面积最大的高原，但其隆升在物种或生物进化中的作用至今仍不清楚。蟾头蜥蜴属于繁殖双峰的沙蜥属（Phrynocephalus），是无性系的一个分支，所有胎生物种仅限于QTP和邻近地区。胎生分类群分布范围的东部被三个密切相关但在分类学上有争议的物种所占据，即P. guinanensis、P. putjatia和P. vlangalii。在这里，我们结合了基因（线粒体ND4基因和9个微卫星位点），形态（11个定量和11个分变量），和生态（九个气候变量）数据，以探索可能的情况下，可能解释遗传和形态模式之间的不一致，并测试是否形态分歧与当地adaptation.ResultsWe发现弱遗传分化，但明显的形态分歧，特别是在几内亚黑杨和Vlangalii黑杨之间。在遗传学上，任何物种对之间的物种界限都不是那么清楚。在形态学上，种间界限明显，而种间界限不明显。个体大小和鳞片性状是种间形态分化的主要原因。形态分歧的栖息地类型，不同climatics.ConclusionsOur研究提供了证据的遗传和形态分歧之间的三个密切相关的胎生物种的Phrynocephalus蜥蜴，并支持的想法，自然选择在空间异质性的环境中，即使在基因流的存在下，可能会导致人口分化。我们的研究支持的假说，胎生沙蜥物种之间的进化分歧是QTP隆起后的环境变化的结果。
BackgroundThe Qinghai-Tibetan Plateau (QTP) is the world's highest and largest plateau, but the role of its uplift in the evolution of species or biotas still remains poorly known. Toad-headed lizards of the reproductively bimodal genus Phrynocephalus are a clade of agamids, with all viviparous species restricted to the QTP and adjacent regions. The eastern part of the range of the viviparous taxa is occupied by three closely related but taxonomically controversial species, P. guinanensis, P. putjatia and P. vlangalii. Here, we combined genetic (mitochondrial ND4 gene and nine microsatellite loci), morphological (11 mensural and 11 meristic variables), and ecological (nine climatic variables) data to explore possible scenarios that may explain the discordance between genetic and morphological patterns, and to test whether morphological divergence is associated with local adaptation.ResultsWe found weak genetic differentiation but pronounced morphological divergence, especially between P. guinanensis and P. vlangalii. Genetically, the species boundary was not so clear between any species pair. Morphologically, the species boundary was clear between P. guinanensis and P. vlangalii but not between other two species pairs. Body size and scale characters accounted best for morphological divergence between species. Morphological divergence was related to habitat types that differ climatically.ConclusionsOur study provides evidence for genetic and morphological divergence among the three closely related viviparous species of Phrynocephalus lizards, and supports the idea that natural selection in spatially heterogeneous environments can lead to population divergence even in the presence of gene flow. Our study supports the hypothesis that the evolutionary divergence between viviparous Phrynocephalus species was a consequence of environmental change after the uplift of the QTP.