Data from: The architecture of river networks can drive the evolutionary dynamics of aquatic populations

It is widely recognized that physical landscapes can shape genetic variation within and between populations. However, it is not well understood how riverscapes, with their complex architectures, affect patterns of neutral genetic diversity. Using a spatially explicit agent-based modeling (ABM) approach, we evaluate the genetic consequences of dendritic river shapes on local population structure. We disentangle the relative contribution of specific river properties to observed patterns of genetic variation by evaluating how different branching architectures and downstream flow regimes affect the genetic structure of populations situated within river networks. Irrespective of the river length, our results illustrate that the extent of river branching, confluence position, and levels of asymmetric downstream migration dictate patterns of genetic variation in riverine populations. Indeed, comparisons between simple and highly branched rivers show a 20-fold increase in the overall genetic diversity and a 7-fold increase in the genetic differentiation between local populations. Given that most rivers have complex architectures, these results highlight the importance of incorporating riverscape information into evolutionary models of aquatic species and could help explain why riverine fishes represent a disproportionately large amount of global vertebrate diversity per unit of habitable area.学界普遍认为，物理景观能够塑造种群内部及种群间的遗传变异。然而，人们对结构复杂的河川景观（riverscape）如何影响中性遗传多样性格局仍知之甚少。本研究采用空间显式基于智能体的建模（spatially explicit agent-based modeling, ABM）方法，探究树形河流水体形态对本地种群结构的遗传效应。通过评估不同分支结构与下游径流情势如何影响河网内种群的遗传结构，本研究厘清了特定河流属性对观测到的遗传变异格局的相对贡献。无论河流长度如何，本研究结果均表明，河流分支程度、汇流位置以及不对称下游迁移水平决定了河流种群的遗传变异格局。诚然，对比简单河道与高度分支河道的结果显示，高度分支河道的整体遗传多样性较简单河道提升20倍，本地种群间的遗传分化则提升7倍。鉴于多数河流都具有复杂的结构，本研究结果凸显了将河川景观信息纳入水生生物进化模型的重要性，同时也有助于解释为何河流鱼类在每单位栖息面积的全球脊椎动物多样性中占比远超预期。