International Research Fellowship Program: The Evoluton of Reproductive Skew in A Communally Breeding Insect

Loeb, Michael L, Arlington VA

Investigators

Abstract

0107355 Loeb The International Research Fellow Awards Program enables U.S. scientists and engineers to conduct three to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad. This award will support a twenty-four month postdoctoral research fellowship by Dr. Michael Loeb to work with Dr. Bernard J. Crespi at Simon Fraser University in Burnaby, Canada. Funding for this project is from the Americas Program of the Division of International Programs. A major goal of evolutionary biology is to develop a unified theory predicting the conditions under which natural selection favors cooperative group living over solitary existence. Central to this goal is to explain why some individuals within groups often limit their own production of offspring and instead assist others in reproduction. Thus, cooperation has costs and the key is to explain how cooperation evolves despite costs. Reproductive skew theory, an extension of kin selection theory, predicts the circumstances under which reproduction is unevenly shared (high-skew societies) or when reproduction is more equitably shared (low-skew societies). In spite of skew theory's potential to unify the study of social evolution, few manipulative field studies have tested its major predictions. The objective of this project is to test two skew theory's predictions using a communally breeding insect as a model system. Dr. Loeb will use populations of the lace bug Leptobyrsa decora introduced to Hawaii. Leptobyrsa decora is an ideal system to test skew theory because kinship among cooperatively breeding females can be manipulated while holding other factors constant. He will test the theoretical expectations that (a) highly related groups show high reproductive skew, and (b) populations with relatively poor conditions for solitary breeding should show higher skew. Dr. Crespi is an authority on insect social systems and he has incorporated reproductive skew theory into his own research program.