Bernstein Justin M, Voris Harold K, Stuart Bryan L, Karns Daryl R, McGuire Jimmy A, Iskandar Djoko T, Riyanto Awal, Calderón-Acevedo Camilo A, Brown Rafe M, Gehara Marcelo, Soto-Centeno J Angel, Ruane Sara
Center for Genomics, University of Kansas, Dyche Hall, 1345 Jayhawk Blvd, Lawrence, KS, 66045, USA.
Life Sciences Section, Negaunee Integrative Research Center, Field Museum, 1400 S. Lake Shore Drive, Chicago, IL, 60605, USA.
Sci Rep. 2024 Mar 12;14(1):4727. doi: 10.1038/s41598-024-54744-z.
Divergence dating analyses in systematics provide a framework to develop and test biogeographic hypotheses regarding speciation. However, as molecular datasets grow from multilocus to genomic, sample sizes decrease due to computational burdens, and the testing of fine-scale biogeographic hypotheses becomes difficult. In this study, we use coalescent demographic models to investigate the diversification of poorly known rice paddy snakes from Southeast Asia (Homalopsidae: Hypsiscopus), which have conflicting dates of origin based on previous studies. We use coalescent modeling to test the hypothesis that Hypsiscopus diversified 2.5 mya during the Khorat Plateau uplift in Thailand. Additionally, we use ecological niche analyses to identify potential differences in the niche space of the two most widely distributed species in the past and present. Our results suggest Hypsiscopus diversified ~ 2.4 mya, supporting that the Khorat Plateau may have initiated the diversification of rice paddy snakes. We also find significant niche differentiation and shifts between species of Hypsiscopus, indicating that environmental differences may have sustained differentiation of this genus after the Khorat Plateau uplift. Our study expands on the diversification history of snakes in Southeast Asia, and highlights how results from smaller multilocus datasets can be useful in developing and testing biogeographic hypotheses alongside genomic datasets.
系统发育学中的分歧时间分析提供了一个框架，用于建立和检验关于物种形成的生物地理学假设。然而，随着分子数据集从多位点发展到基因组，由于计算负担，样本量减少，精细尺度生物地理学假设的检验变得困难。在本研究中，我们使用溯祖种群模型来研究东南亚鲜为人知的稻田蛇（水游蛇科：棱腹蛇属）的多样化情况，此前的研究对其起源时间存在相互矛盾的结论。我们使用溯祖模型来检验棱腹蛇属在泰国呵叻高原隆升期间于250万年前实现多样化的假设。此外，我们使用生态位分析来确定过去和现在分布最广的两个物种在生态位空间上的潜在差异。我们的结果表明，棱腹蛇属在约240万年前实现了多样化，这支持了呵叻高原可能引发了稻田蛇多样化的观点。我们还发现棱腹蛇属物种之间存在显著的生态位分化和转移，这表明在呵叻高原隆升后，环境差异可能维持了该属的分化。我们的研究扩展了东南亚蛇类的多样化历史，并强调了较小的多位点数据集的结果如何能与基因组数据集一起用于建立和检验生物地理学假设。
