The aim of this study is to investigate central questions in sexual selection; Why do mating preferences and sexual ornaments evolve? Why are males usually active in courtship and compete for mates, while females are choosy? Several factors have been suggested to explain sex-roles. Most studies have focused on competition for mates, and only a few studies have attempted to explain sex differences in choosiness; but the operational sex ratio (OSR) and variation in mate quality seem important. This study would be among the first to adress these questions empirically.
Salaria pavo (Pisces: Blenniidae) exhibit paternal care and males devel sexual ornaments. In the study population, the OSR is female-biased and females court and compete for access to males, thus sex-roles are reversed. I will investigate mate choice of both sexes, potential benefits of carrying out mate choice, and the function of the male sexual ornaments. This unique system provides excellent opportunities for testing important sexual selection theory and obtain novel results.