Population connectivity and phylogeography of a coastal fish, Atractoscion aequidens (Sciaenidae), across the Benguela Current region: evidence of an ancient vicariant event.

Contemporary patterns of genetic diversity and population connectivity within species can be influenced by both historical and contemporary barriers to gene flow. In the marine environment, present day oceanographic features such as currents, fronts and upwelling systems can influence dispersal of eggs/larvae and/juveniles/adults, shaping population substructuring. The Benguela Current system in the southeastern Atlantic is one of the oldest upwelling systems in the world, and provides a unique opportunity to investigate the relative influence of contemporary and historical mechanisms shaping the evolutionary history of warm-temperate fish species. Using the genetic variation in the mitochondrial DNA Control Region and eight nuclear microsatellite DNA loci, we identified the presence of two highly divergent populations in a vagile and warm-temperate fish species, Atractoscion aequidens, across the Benguela region. The geographical distributions of the two populations, on either side of ...物种种内的当代遗传多样性格局与种群连通性，可同时受到历史与当代基因流阻隔因素的调控。在海洋环境中，现代海洋学特征（如洋流、海洋锋面与上升流系统）可影响卵、浮游幼体、幼鱼乃至成体的扩散过程，进而塑造种群亚结构。位于东南大西洋的本格拉洋流系统是全球最古老的上升流系统之一，为探究塑造暖温性鱼类物种演化历史的当代与历史机制的相对影响提供了独特研究契机。本研究借助线粒体DNA控制区（mitochondrial DNA Control Region）与8个核微卫星DNA位点（nuclear microsatellite DNA loci）的遗传变异，在本格拉海域分布的具有高扩散能力的暖温性鱼类Atractoscion aequidens中，鉴定出两个高度分化的种群。这两个种群的地理分布分别位于……两侧