Spatial and temporal dynamics of species coexistence: a global approach using snakes and lizards as models

Abstract

In order to understand why species richness varies across space, we need to understand the mechanisms regulating species distributions and their coexistence patterns. Thus, understanding the processes that determine species coexistence is an essential step into understanding what generates and maintains biodiversity. Both the speciation process and the time since divergence between lineages can ascertain when those lineages might come into coexistence. Competition and dispersion can also influence the coexistence probability among lineages. It is important to note, however, that the geographical and ecological scenario where lineages occur should modulate the potential effects of competition and dispersion in coexistence patterns. Moreover, the ecological, physiological and behavioral attributes of each taxonomic group might also influence how different factors affect coexistence. Snakes and lizards (order Squamata) comprise more than 10.000 reptile species distributed worldwide differing in many aspects of their natural history. Thus, the Squamata represents an ideal group to explore species coexistence patterns and the factors shaping them. The goal of this project is to explore the role of speciation, time since divergence, competition, and dispersion, in shaping coexistence patterns among Squamate lineages in different geographical and ecological contexts. We will use phylogenetic information on sister species, distribution maps, morphological data and probabilistic models to investigate what factors determine the spatial and temporal dynamics of coexistence in Squamata. (AU)