DISSERTATION RESEARCH: Evolution of a Spicy Polymorphism

University Of Washington, Seattle WA

Investigators

Abstract

Phenotypic and genetic variation within a species set the foundation for evolution and adaptation. This project will study local adaptation in natural populations of a wild chili, Capsicum chacoense, which has a polymorphism in fruit pungency (heat) that varies geographically in association with moisture availability. Field experiments will be used to test the environmental and biotic causes of variation in pungency and to evaluate the costs/benefits of pungency, the extent of local adaptation in pungency, and the primary ecological drivers maintaining this polymorphism. This project examines the evolutionary processes that have shaped a stable polymorphism in wild chili peppers and explores the role of drought stress, an important agronomic factor, in limiting adaptation. Chilies are a major crop that plays important roles in human diet, and the chemicals that cause its pungency, the capsaicinoids, have medical and security applications. This project includes public outreach and education, as well as training of undergraduates and international collaborations.