A phylogenomic study to unveil ancient contacts between the Amazonia and the Atlantic Forest (Brazil)

The Neotropical region is one of the most biodiverse in the world and several hypotheses have been proposed to explain how it diversified. Some studies, especially with vertebrates, suggest that historical connections between the Amazon Forest (AMZ) and the Atlantic Forest (AF) wereimportant in the diversification history of these biomes. The goal of this study is to unveil patterns and processes associated to historical connections between the AMZ and the AF based on the biogeographic analyses of two genera (Xipholena and Cotinga; family Cotingidae). Our phylogenies and estimates of divergence dates are congruent with a previous hypothesis that bird species from the AF of northeastern Brazil are more closely related to taxa from eastern Amazon and diverged within the Plio-Pleistocene. Results of coalescent simulations and Approximate Bayesian Computation for both genera are congruent with the hypothesis that the AF was colonized by a founding population (bottleneck) that expanded afterwards. This suggests that dispersion played an important role in the AF colonization. Ecological similarity among species of these genera may explain the concordant pattern. Thus, species-specific responses to expansion of the different suitable ecological habitats (ecological niches) are expected to occur and reinforce that ecological attributes can play an important role in these forest connection patterns. This reinforces the need of analyses of a larger number of taxa with different ecologies.