Christopher S. Willett

Christopher S. Willett

Molecular population and evolutionary genetics

Telephone: (919) 843-6290

Office: 436 Wilson Hall

Mailing Address:
CB# 3280, Coker Hall
The University of North Carolina at Chapel Hill
Chapel Hill, North Carolina 27599-3280

Research Associate Professor (Initial Appointment: 2002)
Ph.D., Cornell University, Genetics (1999)
B.S., Michigan State University (1993)

Selected References | CV

Research Interests

Speciation Genetics: Genetic basis of hybrid breakdown in copepods and the appearance of reproductive isolation via sterility
Genetic basis of physiological adaptation: Salinity tolerance in copepods
Detecting the action of selection on proteins: Pheromone-binding proteins in moths
Conservation genetics: Outbreeding depression, population genetics of threatened species

Synopsis

My research addresses the nature of genetic variation that underlies speciation and adaptation. Specifically, I attempt to unravel how genetic changes at the molecular level can lead to phenotypic changes of evolutionary significance. A major thrust of my research program has been to understand how genetic variation within populations translates into variation between populations and species, and to determine the impact of natural selection on this process. In my current work I am targeting specific genetic systems to determine how they could be involved in generating reproductive isolation through hybrid breakdown. I am also examining the physiological and fitness consequences of variation in these targeted genes. My work has been on two different systems-copepods and moths.

Copepods-
The harpacticoid copepod Tigriopus californicus inhabits rocky, intertidal splash pools in a patchy distribution along the west coast of North America . Populations of this species display dramatic genetic differentiation even between relatively proximate localities. Crosses between these populations typically show hybrid breakdown (decreases in fitness of F2 individuals). Understanding the genetic basis of this hybrid breakdown is a major research project in my lab. Studies are also underway to explore whether another form of reproductive isolation (sterility) is present in hybrids. A final copepod project involves understanding the genetic basis of a vital physiological process in these copepods-their ability to survive dramatic changes in salinity.

Moths-
My work on moths dealt with the predominate mode of conspecific mate recognition in moths, the sex pheromone system. Specifically I study a protein, the pheromone-binding protein and how it contributes to discrimination by male moths. I have examined the evolution of this protein in a number of different moth families and have uncovered evidence for natural selection acting on this protein in conjunction with changes in the pheromone systems.