Abstract Moore 9514063 Secondary sexual characters are traits that influence the reproductive success of individuals. These traits, such as elaborate structures, nuptial colors, courtship songs, or sex pheromones, have no function outside of mating. They are often elaborate and may be costly to produce and maintain. Secondary sexual characters develop after adulthood prior to full sexual maturity and are often sexually dimorphic. Elaborate secondary sexual characters are most often associated with males, often change with age, influenced by the environment, and can be conditiondependent. These traits have evolved as a result of sexual selection: i.e. either their impact on male-male competition for mates or their influence on female mating preferences. This study will determine the quantitative genetics and evolution of the male-produced sex pheromone of Nauphoeta cinerea and the social behavior of males and females that is displayed in response to this pheromone. This sexual signal develops after males emerge to adulthood, is sex limited in expression, and changes with age and social experience after it has developed. Further, this signal has apparently evolved as a result of sexual selection; both of the behavioral mechanisms of sexual selection are influenced by variation in this pheromone. Females discriminate among males on the basis of this pheromone, and bias the developmental rates of their offspring by mating discriminatory. The outcome of aggressive social interactions among males is also influenced by this pheromone. Extensive background knowledge and experience in studying this pheromone allows one to address fundamental questions concerning the impacts of variable environments, genetics, and development of this sex pheromone and associated behaviors. The P.I. will determine developmental and age-related changes in this pheromone. In addition he will address how the external environment experienced during development shapes sexually-selected signals and behavior. Fi nally, this will quantify the extent that genetic variation impacts responses to environmental influences. These results will increase our understanding of the genetics and evolution of social signals. These experiments will provide the first information on how the behaviors and signals involved in sexual selection are mediated by plasticity. In addition, they will address the importance of genotype by environment (GxE) interactions for sexual selection.
