A genomic assessment of population structure and gene flow in an aquatic salamander identifies the roles of spatial scale, barriers, and river architecture

Population structure and gene flow of species in lotic environments can be constrained by river network architecture, species life history and heterogeneous local barriers. Identifying the factors that influence population structure and gene flow, especially in species limited to movement within a river network, is vital for understanding the evolutionary and demographic history of a species.
We explored population structure and gene flow for a fully aquatic salamander, the common mudpuppy (Necturus maculosus), in Kentucky (USA) using genomic data. We examined population structure using both parametric and nonparametric methods, and we tested for a history of lineage divergence among identified genetic clusters. We quantified the partitioning of genetic variation at different hierarchical levels, and we tested for signatures of isolation by distance. Additionally, we used coalescent-based model selection to identify a best-fit model of gene flow between our three sampled basins.
We fo...

流水环境中物种的种群结构与基因流可能受到河网结构、物种生活史及异质性局部屏障的制约。明确影响种群结构与基因流的因素——尤其是对那些仅能在河网内移动的物种而言——对于理解物种的演化与种群历史至关重要。
我们利用基因组数据，对美国肯塔基州的全水生蝾螈——普通泥狗（Necturus maculosus）——的种群结构与基因流展开了研究。我们采用参数与非参数方法分析种群结构，并检验已识别遗传集群间的谱系分化历史。我们量化了不同层级遗传变异的分配模式，同时检测了距离隔离的信号。此外，我们通过基于溯祖理论（coalescent-based）的模型选择，确定了三个采样流域间基因流的最优拟合模型。