DISSERTATION RESEACH: Does phenotypic evidence support ecological speciation in western long-eared Myotis bats?

物种是如何形成的是进化生物学的一个核心问题。物种形成的一个过程被称为生态物种形成，当不同的环境促进地理上广泛分布的物种的遗传多样化时，就会发生这种情况。在自然分布广泛的生物体（如蝙蝠）中研究和模拟这一过程特别有用。本项目将探索西部长耳蝙蝠的近亲物种之间的差异。这项工作的一个新方面将是开发一个分析框架，在控制环境变化的同时测试表型和基因型之间的相关性。这一分析管道将向公众开放，并可用于测试各种不同生物的生态物种形成预测。这项工作的结果也将对蝙蝠保护工作具有重要的实际意义。为了将这项研究的发现传达给更广泛的受众，将开发一个专注于Myotis蝙蝠的速度和物种形成模式的在线互动博物馆。本研究将通过对基因组、形态学和环境数据的共同分析，确定北美西部长耳蝙蝠生态物种形成的表型证据。先前的研究结果表明，这些物种遵循一种可能由环境变化促进的物种与基因流动模式。因此，这些蝙蝠物种之间的形态分化与基因流分化模式和环境变化有关的假设将得到验证。具体地说，将使用几何形态计量学方法检查这些物种在不同环境中的颅齿形状和大小变化。一种新的方法来解释遗传和环境的共同变异在物种内和物种之间的形态计量差异。该框架将使用几何形态计量学结合环境生态位和基因组扫描分析来识别可能在不同选择下进化的异常位点。最后，该框架将应用于预测西部长耳蝙蝠的形态变异，并区分物种间的表型趋同和基因流动。这种综合的方法将使我们能够从表型、遗传和环境的角度来理解Myotis蝙蝠的物种形成的速度和模式。

How species are formed is a central question in evolutionary biology. One process involved in species formation is known as ecological speciation, which occurs when different environments promote genetic diversification in a geographically widespread species. It is particularly useful to investigate and model this process in organisms that naturally disperse widely, such as bats. This project will explore differences within and among closely related species of the western long-eared Myotis bats. A novel aspect of this work will be the development of an analytical framework that tests for correlations between phenotypes and genotypes while controlling for environmental variation. This analytical pipeline will be made publicly available, and may be used to test the predictions of ecological speciation in a variety of different organisms. Results from this work will also have important practical implications to bat conservation efforts. To communicate findings from this research to a broader audience, an online interactive museum focused on the tempo and mode of speciation of Myotis bats will be developed. This research will identify phenotypic evidence of ecological speciation in western long-eared Myotis bats of North America by co-analyzing genomic, morphological, and environmental data. Previous findings demonstrate that these species follow a pattern of speciation-with-gene-flow that might have been promoted by environmental changes. Therefore the hypothesis that morphological differentiation among these bat species is associated with both divergence-with-gene-flow patterns and environmental variation will be tested. Specifically, craniodental shape and size variation among these species across different environments will be examined, using geometric morphometric approaches. A novel approach that accounts for both genetic and environmental covariation on morphometric differences within and among species will be developed. This framework will use geometric morphometrics coupled with environmental niche and genomic scan analyses to identify outlier loci that may have evolved under divergent selection. Finally, this new framework will be applied to predict morphometric variation among the western long-eared bats and differentiate between phenotypic convergence and gene flow among species. This integrative approach will allow us to understand the tempo and mode of speciation of Myotis bats from a phenotypic, genetic and environmental perspective.