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中心问题。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性时，就会发生生态物种形成。在蝙蝠等自然分散的生物体中对这一过程进行研究和建模尤其有用。这个项目将探索西方长耳蝙蝠近缘物种内部和之间的差异。这项工作的一个新方面将是开发一个分析框架，在控制环境变异的同时测试表型和基因型之间的相关性。这一分析管道将公之于众，并可能用于测试对各种不同生物体的生态物种形成的预测。这项工作的结果也将对蝙蝠保护工作产生重要的实际影响。为了将这项研究的结果传达给更广泛的受众，将开发一个在线互动博物馆，重点关注Myotis蝙蝠的节奏和物种形成模式。这项研究将通过联合分析基因组、形态和环境数据，确定北美西部长耳蝙蝠生态物种形成的表型证据。以前的发现表明，这些物种遵循的是物种形成和基因流动的模式，这种模式可能是由环境变化推动的。因此，这些蝙蝠物种之间的形态分化既与基因流动模式分化有关，又与环境变化有关的假设将得到检验。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头牙形状和大小差异。将开发一种新的方法，解释物种内部和物种之间形态测量差异的遗传和环境协变。这个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值基因座。最后，这个新的框架将被应用于预测西方长耳蝙蝠的形态变异，并区分表型趋同和物种间的基因流动。这种综合的方法将使我们能够从表型、遗传和环境角度了解Myotis蝙蝠的物种形成节奏和模式。

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.