Diversification dynamics of interspecific competition: the role of niche similarity and spatial overlap

Abstract

Most macroevolutionary approaches designed to study the role of species interactions on diversification dynamics have relied on rather indirect evidence. Interspecific competition has been the most often studied kind of interaction. The following patterns have been interpreted as evidence of competition: a- statistical association between diversity trajectories of two potential competitor clades; b- the inference of diversity- dependent diversification dynamics (within or between clades); c- a statistical association between diversification rates of two clades. Additionally, most previous studies have not explicitly taken into account spatial overlap, except perhaps by doing analysis at the continental level. That said, the field of macroevolution has recently advanced by developing new processed-based models devoted to study interspecific competition. Unfortunately, those have, for the most part, been focused on the use of molecular phylogenies and on the effect of species interactions on trait evolution. Here we propose to develop new models that better capture the nature of interspecific competition and use those models to study the effect of interspecific competition within and between clades on diversification dynamics. More specifically, we will develop and use models that take into account niche similarity and spatial overlap to build times series that described the "intensity of competition". Birth-death hierarchical Bayesian models [4] will be used to investigate if those times series describing the "intensity of competition" are associated with changes in speciation and extinction rates. Given the lack of such models designed with fossil data, those will be developed here. Different lineages of mammals, in particular families within Carnivora, will be used as study systems. (AU)