Biological Sciences, Louisiana State University
Saturday 1:45-2:00, Ballroom A
The relative importance of processes such as environmental filtering, historical events and neutral dynamics driving observed patterns of change in community composition across space (beta diversity), remains uncertain. In the case of Neotropical primate communities, many potential drivers of large-scale beta diversity have been proposed, including climate, dispersal limitation and historical/biogeographic events. However, most of these studies have investigated only the taxonomic dimension of biodiversity. Here I assess the relative importance of multiple drivers of community structure in the phylogenetic component of biodiversity, which takes into consideration species evolutionary histories. I deconstruct phylogenetic beta diversity of Neotropical primate communities (> 100 species) into its turnover (change in species composition because of species replacements) and nestedness components (change in species composition because of species richness differences), and assess the relative influence of multiple mechanisms proposed to cause this variation. Preliminary results suggest Platyrrhine phylogenetic beta diversity is mainly caused by spatial turnover, with nestedness contributing with a small fraction. Highly nested communities were located in areas with high environmental variation, while those represented by higher levels of spatial turnover were found in areas that have experimented greater climatic stability. Furthermore, compositional variation accounted for “purely by space” was greater than the “unique environmental” contributions for both components of phylogenetic beta diversity. These results suggest that primate phylogenetic beta diversity reflects a complex interaction of spatial turnover and, to a lesser extent, nestedness, which may be driven by dispersal and environmental dynamics of the region.