DISSERTATION RESEARCH: Co-estimating species responses to climatic variation in the Pleistocene using comparative phylogeography of closely related flying frogs across Sumatra

这项研究调查了导致印度尼西亚两个最大岛屿上广泛物种多样性的进化过程：苏门答腊和爪哇。关于物种如何在这些岛屿上起源，我们知之甚少，但过去的地质和气候事件可能促进了植物和动物的多样化。该项目将利用遗传数据调查历史气候变化如何影响12种跳伞蛙（树蛙属）的多样化。通过使用几个物种，这项研究将梳理出影响其多样化的共同因素。研究结果将揭示物种如何在岛屿上起源，并提供更广泛的了解气候变化如何影响物种分布和多样化。该项目将培训和指导美国学生，扩大代表性不足的群体对科学的参与，促进广泛的国际合作，并为保护实践提供信息。这项研究将测试更新世气候变化如何影响苏门答腊和爪哇的物种分布和多样化。以树蛙属飞蛙为系统，本计画将利用比较生态地理学来共同评估物种组合对高地与低地物种气候变化的反应。本研究将采用外显子靶捕获方法对来自苏门答腊和爪哇的12种树蛙的~1000个外显子进行测序。该项目将使用近似贝叶斯计算模型测试方法来测试末次冰期最大期物种扩张或收缩的假设。利用基因组数据，研究人员将测试高原物种的收缩，以及随着海平面下降而在低地物种的扩张，但整个巽他大陆架的森林收缩。此外，他们将估计来自苏门答腊和爪哇的所有Rhacophorus的强大的同源性，建立在以前为该项目生成的线粒体和双消化RADseq数据的基础上。这项研究的结果将补充以前的研究，调查更新世气候驱动的多样化在热带森林，和热带岛屿的多样化，揭示了组合范围和物种特异性的过程，推动了巽他大陆架的多样化。

This research investigates the evolutionary processes that have led to the extensive species diversity on two of the largest islands in Indonesia: Sumatra and Java. Very little is known regarding how species originated on these islands, but it is likely that past geologic and climatic events facilitated the diversification of plants and animals. This project will use genetic data to investigate how historical climate variation has influenced the diversification of twelve species of parachuting frogs (genus Rhacophorus). By using several species, this study will tease apart the common factors that influenced their diversification. Results will shed light on how species originate on islands, and provide broader insight on how changing climate affects species distributions and diversification. The project will train and mentor U.S. students, broadening participation in science by underrepresented groups, facilitating extensive international collaboration, and informing conservation practices. This research will test how Pleistocene climate variation influenced species distributions and diversification on Sumatra and Java. Using Rhacophorus flying frogs as a system, this project will utilize comparative phylogeography to co-estimate species assemblage responses to climate variation of both highland and lowland species. This study will employ an exon target capture approach to sequence ~1000 exons for twelve Rhacophorus species from Sumatra and Java. This project will test hypotheses of species expansions or contractions during the last glacial maximum using an Approximate Bayesian Computational model-testing approach. Using genomic data, the researchers will test for contraction in highland species, and expansion in lowland species as sea levels lowered, but forests contracted across the Sunda Shelf. Additionally, they will estimate a robust phylogeny for all Rhacophorus from Sumatra and Java, building upon previous mitochondrial and double-digest RADseq data generated for this project. The results of this study will complement previous studies investigating both Pleistocene climate-driven diversification in tropical forests, and tropical island diversification by revealing the assemblage-wide and species-specific processes that have driven diversification on the Sunda Shelf.