PDF(Pubmed)
Abstract：
Recent work has revealed the importance of contemporary evolution in shaping ecological outcomes. In particular, rapid evolutionary divergence between populations has been shown to impact the ecology of populations, communities, and ecosystems. While studies have focused largely on the role of adaptive divergence in generating ecologically important variation among populations, much less is known about the role of gene flow in shaping ecological outcomes. After divergence, populations may continue to interact through gene flow, which may influence evolutionary and ecological processes. Here, we investigate the role of gene flow in shaping the contemporary evolution and ecology of recently diverged populations of anadromous steelhead and resident rainbow trout (Oncorhynchus mykiss). Results show that resident rainbow trout introduced above waterfalls have diverged evolutionarily from downstream anadromous steelhead, which were the source of introductions. However, the movement of fish from above to below the waterfalls has facilitated gene flow, which has reshaped genetic and phenotypic variation in the anadromous source population. In particular, gene flow has led to an increased frequency of residency, which in turn has altered population density, size structure, and sex ratio. This result establishes gene flow as a contemporary evolutionary process that can have important ecological outcomes. From a management perspective, anadromous steelhead are generally regarded as a higher conservation priority than resident rainbow trout, even when found within the same watershed. Our results show that anadromous and resident O. mykiss populations may be connected via gene flow, with important ecological consequences. Such eco-evolutionary processes should be considered when managing recently diverged populations connected by gene flow.
摘要：
最近的工作揭示了当代进化在塑造生态结果方面的重要性。特别是,种群之间的快速进化差异已被证明会影响种群的生态，社区,和生态系统。虽然研究主要集中在适应性差异在种群之间产生生态重要变化中的作用，人们对基因流在塑造生态结果中的作用知之甚少。发散后，种群可能继续通过基因流相互作用，这可能会影响进化和生态过程。这里,我们研究了基因流在塑造最近分化的anadroquoussteelhead和常驻虹鳟鱼（Oncorhynchusmykiss）种群的当代进化和生态学中的作用。结果表明，瀑布上方引入的虹鳟鱼在进化上与下游的无缘钢头不同，这是介绍的来源。然而,鱼类从瀑布上方到瀑布下方的运动促进了基因流动，重塑了房源种群的遗传和表型变异。特别是,基因流动导致居住频率增加，这反过来又改变了人口密度，尺寸结构，和性别比例。这一结果将基因流确立为当代进化过程，可以产生重要的生态结果。从管理的角度来看,食水硬头通常被认为是比常驻虹鳟鱼更高的保护重点，即使是在同一个分水岭里发现的.我们的结果表明，非房性和常驻O.mykiss种群可能通过基因流连接，具有重要的生态后果。在管理通过基因流连接的最近分散的种群时，应考虑这种生态进化过程。
