9629460 HARRIS The factors that affect growth and decline of populations in nature remain elusive, in part because the importance of social interactions has been underestimated. Drs. Harris and Knight propose to study joint nesting behavior in a salamander species and relate that behavior to changes in population size over time. For example, populations that contain a high percentage of joint nesters may be larger in size than populations that contain a high percentage of solitary nesters. In addition, they will investigate whether joint nesters are the result of cooperative interactions among relatives. Methods will include experiments in the laboratory, field observations, and the use of DNA fingerprinting techniques. Results may indicate that existing predictive models of population growth and decline that treat all individuals as identical are inadequate and that the incorporation of behavioral variation among individuals into predictive population models may a necessity. Furthermore, data derived from this detailed population study may provide insights into the causes of an alarming decline in amphibian populations in many areas of the world. Active participation of undergraduate students in all aspects of this research will prepare them for careers in the biological sciences.
