This research explores how ecological and evolutionary processes interact to maintain species diversity in natural communities. Classic ecological theory predicts that immigration can allow species that are poor competitors for resources to persist in natural communities, thereby maintaining regional biodiversity. However, topography, moisture, forest cover, and other landscape conditions cause variation in rates of immigration among local communities. These landscape conditions should also influence local adaptation of species by creating variation in gene flow. Therefore, differences in adaptation and immigration within species may be as important for understanding patterns of biodiversity as differences among species. The goal of this project is to understand how local adaptation and competitive interactions among species are affected by variation in immigration and gene flow within species. This research will test the hypothesis that species coexistence and the resulting pattern of biodiversity in complex landscapes are products of the interactive, adaptive effects of gene flow and the demographic effects of immigration. This project will focus on two species of stream salamander for which there is much prior research on their ecological interactions, but little is known about the effects of immigration and gene flow on species coexistence. The two study species occur together throughout the Appalachian Mountains despite a large difference in competitive ability, and previous studies have documented landscape effects on immigration and gene flow in both species.
This project will create OPEnBio: Opportunities and Perspectives in Environmental Biology, a professional career exploration program that capitalizes on the diversity of people and institutions in environmental biology in New England and the Northern Rockies. Internships will be offered in both regions to attract American Indian undergraduates, who will get to know diverse role models and engage in a variety of approaches to research, application, and outreach. Through related coursework and links to other diversity programs, OPEnBio will increase retention of underrepresented students, show them diverse perspectives in science, and expand the use of traditional ecological knowledge in environmental biology.
