Female Variability and the Nature of Male Quality

Abstract Zuk 9514055 This project will examine the ways in which the sexes differ in both behavior and physiology, concentrating on the role of variation among females in determining the out come of sexual selection, and a definition of male quality that can be used to assess condition or vigor under a wide range of circumstances. By examining female behavior and morphology, and by using indices of immunocompetence to analyze male quality, the research will extend knowledge of universal, a measure of condition or quality which reflects immune system competence is clearly linked to an individual s fitness. Using captive red jungle fowl, the work builds on previous studies showing that females prefer to mate with males with large, colorful combs, and that infection of males with an intestinal parasite hampers the development of the same characters used by females in choosing mates. In addition, highly ornamented individuals, have fewer circulating lymphocytes, suggesting that such males pay a price in terms of reduced immune competence by appearance, and immune response, and will integrate basic and applied research in behavior and immunology. The outcome will be a better understanding of how behavior, including aggressive behavior and stressful experiences, is reflected in immune system parameters that are relevant to the health of all animals.