UC Riverside

In general terms, the overall goal of my dissertation is to acquire a better understanding of the phylogenetic relationships within the most diverse group of snakes in the Neotropics (i.e., the family Dipsadidae) and then use this information to identify the drivers of diversity patterns of the group at multiple spatial scales. To reach this objective, I integrate methodologies, concepts, and hypotheses from phylogenetics, macroecology, and community ecology. For Chapter 1 of my dissertation, I explored the potential causes of phylogenetic uncertainty in one of the two main groups of the Dipsadidae (i.e., the Xenodontinae) using phylogenomic data and a careful examination of the observed gene tree discordance and its potential impact on species tree inference. Although I did not recover a strong resolution of several recalcitrant nodes, I identified the potential factors driving gene tree discordance in the group, apart from finding strong and consistent support for other dipsadid lineages. For Chapter 2, I evaluated the potential drivers of species richness of the Dipsadidae across the entire American continent. In this regard, I recovered that regional diversification had the most important role in determining species richness variation across the distribution of the group. Finally, for Chapter 3 of my dissertation, I investigated the influence of a large-scale biogeographic event (the Great American Biotic Interchange, GABI) on the current species and functional diversity of a series of communities of the Dipsadidae across the Neotropics. Despite the increased input of taxa following the GABI, I did not recover that the communities involved in this event ended up being more diverse at this current time. Such a result indicates that in these communities, an equilibrium point has been reached between the processes of colonization and biotic interactions. In general, my studies continue with and expand upon the increasing recognition of the importance of phylogenetics in different areas of ecology and vice versa. Further, it is based on methodologies that can easily be implemented in other lineages and thus contribute to identifying more generalizable patterns about the drivers of species richness at the local and regional scales.