How Does Gene Flow Affect Local Adaptation and Population Dynamics?: Experimental Tests in Wild Populations and Mesocosms

该项目测试基因流动的影响，即移民将基因从一个种群转移到另一个种群，对特立尼达孔雀鱼的当地适应和种群动态的影响。一方面，基因流动可能通过引入不适应基因而破坏局部适应，降低适应度。另一方面，基因流动可能通过增加遗传变异来增加小型近交群体的适应性。此外，基因流动可能对种群的生长和动态有重要影响。研究人员将在野生种群和受控制的mesocosms（实验池）中进行实验，以测试基因流动的影响。首先，他们将确定适应不同环境的鱼类的迁移如何影响野生种群的特征和适应性。接下来，他们将测试这些性状和适应性的变化如何影响种群动态。最后，他们将通过实验测试基因流动的影响如何随着种群间适应性分化的程度和近亲繁殖的水平而变化。这项研究利用了一个难得的机会来检查野生和中生态环境中基因流动发生前后的种群。该项目的结果将为保护计划提供信息，因为一种常用但很少测试的保护策略是人为地增加基因流动。除了研究之外，研究人员还将扩大他们创新的“孔雀鱼工具包”计划，让美国和特立尼达的中小学生在课堂上使用孔雀鱼来接触实验进化生物学。该研究还将为代表性不足的少数民族和特立尼达本科生提供实地、实验和分子研究方面的培训。OISE为该研究的国际部分提供了共同资助。

This project tests the effects of gene flow, the movement of genes from one population to another by immigrants, on local adaptation and population dynamics in Trinidadian guppies. On the one hand, gene flow may break down local adaptation and reduce fitness by introducing maladapted genes. On the other hand, gene flow may increase fitness by adding genetic variation to small, inbred populations. Moreover, gene flow may have important effects on population growth and dynamics. The researchers will test the effects of gene flow using experiments in wild populations and in controlled mesocosms (experimental pools). First, they will determine how immigration of fish adapted to a different environment affects traits and fitness in wild populations. Next, they will test how these changes in traits and fitness affect population dynamics. Lastly, they will experimentally test how the effects of gene flow vary with the degree of adaptive differentiation between populations and the level of inbreeding.This study takes advantage of a rare opportunity to examine populations before and after the onset of gene flow in the wild and in mesocosms. Results of this project will inform conservation programs since a commonly used, but rarely tested, conservation strategy is to artificially increase gene flow. Alongside the research, the investigators will expand their innovative "guppy kit" program to expose elementary and middle school students to experimental evolutionary biology using guppies in the classroom in both the US and in Trinidad. The research will also provide training in field, experimental, and molecular research for underrepresented minorities and Trinidadian undergraduate students. Co-funding for the international component of the research has been provided by OISE.