Michael McEntire, Brigham Young University
Biology
Female mate choice (intersexual selection) and male dominance interactions (intrasexual selection) can each play important roles in sexual selection. These two mechanisms tend to be discussed in isolation. The goal of this study is to explore the interaction between these two forms of sexual selection. To test this idea, we focused on the livebearing tropical fish system Poecilia gillii. We grouped males into similarly sized pairs and observed them for a week to determine which male was dominant. These pairs were then presented to females in mate choice trials to ascertain female preference. We also photo- graphed the males to determine coloration. We found that females were unable to detect dominant males without viewing the physical contest and that carotenoid coloration bore no effect on female preference. Females tended to choose the male to their left, suggesting the preferential use of their right eyes in making decisions on mate choice.