The Evolution of Stable Intermediate Levels of Reproductive Isolation

University Of North Carolina At Chapel Hill, Chapel Hill NC

Investigators

Abstract

When unique but related species overlap geographically with one another, there are specific conditions that determine whether they will fuse into one species (a form of extinction), or will be able to evolve mechanisms to prevent the exchange of genes between them. This research investigates conditions that allow a third possibility, that two species may reach a stable state where they still exchange some genes, but are yet able to retain their specific identities. The research team will expand upon initial models that identified the existence of these stable states of partial isolation, using mathematical models that exactly replicate the effects of migration between populations, differential survival, and mate choice. Specifically, initial models by the PI and others will be extended in several ways to allow for additional phenomena that greatly extend their applicability. Delineating the conditions that can lead to partial isolation is important both in developing a basic understanding of how species can remain distinct from one another, and in comprehending the possible consequences of the breakdown of geographic barriers between species, an increasingly common occurrence under human disturbance. As part of this project, the PI will continue to develop a "mathematical track" in an introductory biology course at UNC, which uses a variety of techniques to reduce math anxiety, a problem documented to disproportionally affect the performance of women. This track thus promotes both the participation of women in the mathematical sciences and more generally addresses the need to integrate math into the undergraduate biology curriculum.