Hotspots of Genome Evolution in a Rapid Vertebrate Radiation

进化辐射是一群以异常高的速度产生新物种的生物体。生物学家长期以来一直使用这种辐射作为模型系统来研究物种形成的过程。过去的研究通常集中在可能促进新物种形成的生物体或其栖息地的特征上。然而，随着基因组测序方法的发展，现在有可能确定可能参与产生进化辐射的特定基因。该项目旨在确定可能与北美，中美洲和南美洲一群小型，色彩鲜艳的鸣禽异常多样化有关的基因。该项目提供了一个丰富的机会，了解进化辐射的遗传基础和基质，已经引起了最多样化的脊椎动物物种群体之一。该项目将包括对本科生和研究生的培训和指导，以及将研究扩展到更广泛社区的外展计划。该研究项目的重点是林莺（Parulidae），这是一个拥有100多个物种的鸟类家族，在过去的1000万年中多样化，并且是鸣禽中进化速度最快的鸟类之一。该项目的目标是研究可能参与这一群体多样化的基因的进化历史。一个重要的出发点是需要对所涉及的潜在候选基因有一定的了解，这是几乎所有非模型生物系统所缺乏的。然而，在莺，以前的研究独立的杂交区产生了一组候选基因组区域与物种的差异，其中许多已被发现参与羽毛色素沉着。该项目利用系统发育比较方法的工具和理论框架，将分析辐射中每个物种多个个体的全基因组序列数据。这项工作将首先量化密切相关物种之间的基因组差异模式，以确定与特殊谱系特异性进化相关的染色体区域和基因。其次，研究人员将估计在辐射中物种基因组中取样的树木拓扑结构中的谱系不一致性，以测试网状进化的证据。最后，通过利用鸟类生命树中广泛存在的基因组，该项目将超越莺，以解决进化辐射中有关非凡物种形成的基本问题：是否存在多样化的基因组预测因子？该奖项反映了NSF的法定使命，并被认为是值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估的支持。

Evolutionary radiations are groups of organisms that produce new species at an exceptionally high rate. Biologists have long used such radiations as model systems to study the process of speciation. Past studies have commonly focused on the traits of organisms or their habitats that might have facilitated the formation of new species. With the development of genome sequencing methods, however, it is now possible to identify specific genes that might be involved in producing evolutionary radiations. This project aims to identify genes that may be associated with the exceptional diversification of a group of small, colorful songbirds in North, Central, and South America. The project offers a rich opportunity to understand the genetic bases of evolutionary radiations and the substrate that has given rise to one of the most diverse vertebrate species groups. The project will include training and mentorship of undergraduate and graduate students, as well as outreach programs to extend the research to the broader community.The research project focuses on wood warblers (Parulidae), a family of birds with over 100 species that diversified within the last 10 million years, and which has one of the fastest evolutionary rates across songbirds. The goal of the project is to study the evolutionary history of genes potentially involved in the diversification of this group. An important starting point requires some knowledge of potential candidate genes involved, something lacking in nearly all non-model biological systems. In warblers, however, previous studies of independent hybrid zones have generated a set of candidate genomic regions associated with species differences, many of which have been found to be involved in plumage pigmentation. The project draws upon the tools and theoretical framework of phylogenetic comparative methods and will analyze whole genome sequence data from multiple individuals of every species in the radiation. The work will first quantify patterns of genomic divergence among closely related species to identify chromosomal regions and genes associated with exceptional lineage-specific evolution. Second, the researchers will estimate genealogical discordance in the topologies of trees sampled across the genomes of species in the radiation to test for evidence of reticulate evolution. Finally, by making use of the widespread availability of genomes across the avian tree of life, the project will extend beyond warblers to address a fundamental question regarding the extraordinary speciation within evolutionary radiations: are there genomic predictors of diversification?This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.