Graduate Fellow

The role of divergence in multiple sexually selected traits in speciation by sexual selection

PI(s): Elizabeth Scordato (University of Chicago)
Start Date: 11-Mar-2012
End Date: 31-Mar-2012
Keywords: speciation, sexual selection, comparative methods

The role that sexual selection plays in the speciation process remains a controversial topic. Theoretical models have shown that sexual selection can drive population divergence under certain conditions, but predictions from models are difficult to generalize to natural systems, and therefore have not been rigorously tested by empiricists. The working group “An integrative evolutionary approach to examine sexual selection as a mechanism of speciation”, led by Drs Rebecca Safran and Al Uy, is synthesizing empirical data and theoretical models with the goal of generating explicit, testable predictions about the role of sexual selection in population divergence. We have now compiled a database of nearly 350 studies that are ready for analysis. I am interested in examining whether multiple sexually selected traits accelerate or impede speciation. I propose using our empirical review data for formal meta-analyses and comparative analysis to study the role of multiple sexually selected traits in population divergence. I aim to address two major questions. First, is reproductive isolation more likely to evolve if more than one sexually selected trait diverges between populations or closely related species? Second, are certain classes of sexually selected traits (e.g. acoustic vs. color) more frequently associated with the evolution of reproductive isolation? These questions have rarely been addressed in single systems, much less synthesized across taxa, and will address outstanding questions in the empirical literature. Moreover, they are directly related to my thesis research, which focuses on multi-trait sexual selection during incipient speciation in an avian ring species.