Late Pleistocene landscape changes and habitat specialization as promoters of population genomic divergence in Amazonian floodplain birds

We combined landscape history and habitat specialization to understand the historical and ecological factors responsible for current levels of genetic divergence in three species of birds specialized in seasonally flooded habitats in muddy rivers which are widespread in the Amazon basin but have isolated populations in the Rio Branco. Populations of the White-bellied Spinetail (Mazaria propinqua), Lesser Wagtail-tyrant (Stigmatura napensis), and Bicolored Conebill (Conirostrum bicolor) are currently isolated in the Rio Branco by the black-waters of the lower Rio Negro, offering a unique opportunity to test the effect of river color as a barrier to gene flow. We used ultraconserved elements (UCEs) to test alternative hypotheses of population history in a comparative phylogeographic approach by modeling genetic structure, demographic history, and testing for shared divergence time among co-distributed taxa.