Tropical specialist vs. climate generalist: Diversification and demographic history of sister species of Carlia skinks from northwestern Australia
Tropical specialist vs. climate generalist: Diversification and demographic history of sister species of Carlia skinks from northwestern Australia
复制标题
DOI：
10.1111/mec.14185
复制
发表时间：
2017-08-01
影响因子：
4.9
通讯作者：
Moritz, Craig
中科院分区：
文献类型：
--
作者：
Afonso Silva, Ana C.;Bragg, Jason G.;Moritz, Craig
热带地区特有的物种预计将容易受到未来气候变化的影响，部分原因是它们的气候生态位相对较窄。此外，这些物种更有可能对过去的气候变化做出了强烈的反应，这可以通过系统地理分析来探索。为了验证热带专家比气候通才对气候变化更敏感的假设，我们生成并分析了来自mtDNA和类似于2500个外显子的序列数据，以比较澳大利亚彩虹鱼两个姊妹物种的历史持久性和种群波动的规模：热带专家Carlia johnstonei和气候通才C.triacantha。我们预计热带特产物种将具有更深更细的系统地理结构和相对于密切相关的气候通才物种更强的人口波动，后者在第四纪晚期的恶劣气候时期本应具有更稳定的种群。在C.johnstonei内，我们发现来自金伯利群岛北部的一些种群与大陆种群高度分化。在三棘豆中，一个主要分支出现在沙漠中，进入中部顶端，另一个主要出现在金伯利山脉，记录向东零星分布。当它们的范围在金伯利山脉重叠时，线粒体DNA和核DNA都表明热带专家内部有更强的系统地理结构和范围扩展，而气候通才的结构最小，没有证据表明最近过去的范围扩展。这些结果与热带专家对过去气候变化更敏感的假设是一致的。
Species endemic to the tropical regions are expected to be vulnerable to future climate change due in part to their relatively narrow climatic niches. In addition, these species are more likely to have responded strongly to past climatic change, and this can be explored through phylogeographic analyses. To test the hypothesis that tropical specialists are more sensitive to climate change than climate generalists, we generated and analyse sequence data from mtDNA and similar to 2500 exons to compare scales of historical persistence and population fluctuation in two sister species of Australian rainbow skinks: the tropical specialist Carlia johnstonei and the climate generalist C. triacantha. We expect the tropical specialist species to have deeper and finer-scale phylogeographic structure and stronger demographic fluctuations relative to the closely related climate generalist species, which should have had more stable populations through periods of harsh climate in the late Quaternary. Within C. johnstonei, we find that some populations from the northern Kimberley islands are highly divergent from mainland populations. In C. triacantha, one major clade occurs across the deserts and into the mesic Top End, and another occurs primarily in the Kimberley with scattered records eastwards. Where their ranges overlap in the Kimberley, both mitochondrial DNA and nuclear DNA suggest stronger phylogeographic structure and range expansion within the tropical specialist, whereas the climate generalist has minimal structuring and no evidence of recent past range expansion. These results are consistent with the hypothesis that tropical specialists are more sensitive to past climatic change.