Genomic data reject the hypothesis of sympatric ecological speciation in a clade of Desmognathus salamanders.

摘要: Closely related taxa with dissimilar morphologies are often considered to have diverged via natural selection favoring different phenotypes. However, some studies found these scenarios be paired limited or no genetic differentiation. Desmognathus quadramaculatus and D. marmoratus sympatric salamander species thought represent a case of ecological speciation based on distinct morphologies, but the results previous not resolved corresponding patterns lineage divergence. Here, we use genome-wide data test this hypothesis speciation. Population structure analyses partitioned individuals geographically, morphologically, into two adjacent regions western North Carolina: Pisgah Nantahala. Phylogenetic confirmed nominal nonmonophyletic deep divergence between geographic clusters. Model-testing overwhelmingly supported that followed geography. Finally, niche modeling showed Nantahala occupy climatic niches, boundaries for lineages correspond differences in precipitation regimes across southern Appalachia. Overall, reject microhabitat partitioning. Instead, our suggest there cryptic lineages, each containing same pair morphotypes.