MCA: Genomic diversification and speciation along ecological gradients in a marine fish radiation

对于进化生物学家来说，了解海洋环境中新物种的形成已被证明是一项具有挑战性的任务。高水平迁徙的可能性和明显缺乏地理障碍造成了生态多样化和生活史转变在物种形成过程中可能很重要的情况。这项研究计划将确定沿纬度和深度梯度的密切相关物种和种群之间的差异的基因组基础，以确定适应在物种形成过程中的作用。岩鱼(Sebases)是研究这些问题的理想系统，因为它们是生活在广泛生境的各种温带鱼类，它们受到了许多系统发育研究的影响。这项研究将建立在越来越多的旨在更好地了解海洋环境中物种形成过程的研究的基础上。加州州立大学洛杉矶分校将为本科生和研究生提供培训机会，该项目的数据也将作为管理岩鱼的资源，其中许多是商业上重要的。该项目将利用基因组扫描和从头基因组组装来测试与生态(深度)或地理(纬度)梯度的分歧有关的岩鱼的物种形成历史。这些发现可以用来更好地理解自然选择在基因组中的作用，以及这如何有助于这一群体的多样化。研究的第一个方面将考察沿深度梯度的生态适应在新物种形成中所起的作用。第二个方面将把这些发现与密切相关物种之间的纬度差异进行对比。综上所述，这些结果将为密切相关的海洋物种的物种形成历史和基因组差异提供新的见解，并为理解选择和遗传漂移在产生和维持海洋多样性方面的相对作用提供一个框架。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Understanding the formation of new species in the marine environment has proven to be a challenging task for evolutionary biologists. The potential for high levels of migration and the apparent lack of geographical barriers create a scenario where ecological diversification and life history shifts are likely important in the speciation process. This research program will determine the genomic basis of divergence among closely related species and populations along latitudinal and depth gradients to determine the role of adaptation in the speciation process. Rockfish (Sebastes) are an ideal system to examine these questions as they are a diverse group of temperate fishes inhabiting a wide array of habitats, and they have been subject to numerous phylogenetic studies. This study will build upon a growing set of studies aimed at better understanding the speciation process in the marine environment. Training opportunities will be provided to undergraduate and graduate students at Cal State LA, and data from this project will also serve as a resource for the management of rockfish, many of which are commercially important.This project will utilize genome scans and de novo genome assemblies to test for speciation histories of rockfish associated with divergence along ecological (depth) or geographic (latitude) gradients. These findings can be used to better understand the role of natural selection on the genome and how this contributes to the diversification of this group. The first aspect of the study will examine the role that ecological adaptation along a depth gradient has played in the formation of new species. The second aspect will contrast these findings with latitudinal divergence among closely related species. Together these results will provide novel insights into the speciation history and genomic divergence for closely related marine species, and provide a framework for understanding the relative roles of selection and genetic drift on generating and maintaining marine diversity.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.