Quantitative genetics and population genomics of repeated complex trait evolution

项目摘要 复杂的表型是一套适应性特征，有助于一个共同的功能。一个 重要的挑战是了解这些表型是如何进化和维持的， 人口数量。理论预测，复杂性状的进化及其在自然界中的保存， 基因流的面貌将取决于性状分歧的遗传结构， 遗传变异的类型和来源，以及生殖隔离障碍的存在。 然而，我们缺乏实证系统来严格检验这些理论预期。而 新兴模式分类群重复表型进化的遗传基础研究 提供了一个机会，是否，以及多久，进化通过类似的基因， 重复进化的研究往往只涉及两个或三个过程的比较， 血统，很少研究复杂的特征。我的研究小组将弥合这些差距， 研究花授粉综合征的进化遗传学，这是一种复杂的适应， 一个植物属。在这个属中，一种新的综合征表型已经进化了至少20 独立时报我的团队将启动旨在系统量化的研究方向 控制复杂性状的进化和维持的遗传和基因组特征 多样性，利用Penstemon中的特殊并行性。我们将检查基因和 使用重复QTL分析的适应性趋异的基因组结构，确定 复杂性状的元素显示遗传平行性，评估是否存在变异或 基因流作为遗传变异的来源，并研究了性状变异的复杂性 在最近分歧的物种使用人口基因组数据。这种综合性的工作 将有助于制定一个总体框架， 通过什么机制，表型进化受到遗传机制的制约。换句 换言之，这些数据将阐明生物体基因组的固有灵活性和局限性， 适应新的环境挑战。

PROJECT SUMMARY Complex phenotypes are suites of adaptive traits that contribute to a shared function. An important challenge is understanding how such phenotypes evolve and are maintained in populations. Theory predicts that the evolution of complex traits and their preservation in the face of homogenizing gene flow will depend on the genetic architecture of trait divergence, the types and sources of genetic variation, and the presence of reproductive isolating barriers. However, we lack empirical systems to rigorously test these theoretical expectations. While investigations into the genetic basis of repeated phenotypic evolution in emerging model taxa provide an opportunity whether, and how often, evolution proceeds through similar genetic processes, studies of repeated evolution have often involved comparison of only two or three lineages, and rarely have studied complex traits. My research group will bridge these gaps by investigating evolutionary genetics of floral pollination syndrome, a complex adaptation, in the plant genus Penstemon. In this genus, a novel syndrome phenotype has evolved at least 20 independent times. My group will initiate research directions aimed at systematically quantifying genetic and genomic features governing the evolution and maintenance of complex trait diversity, leveraging the exceptional parallelism in Penstemon. We will examine the genetic and genomic architecture of adaptive divergence using replicate QTL analyses, determine which elements of complex traits display genetic parallelism, assess whether standing variation or gene flow act as a source of genetic variation, and examine how complex trait variation is maintained in recently diverged species using population genomic data. This integrative work will contribute to the development of a general framework for understanding whether, and through what mechanisms, phenotypic evolution is constrained by genetic mechanisms. In other words, such data will illuminate the inherent flexibility and limits of an organism's genome to adapt to novel environmental challenges.