FALLAHPOUR, Kamelia; ESPINOZA, Robert E.; California State Univ. Northridge; California State Univ. Northridge: Female breeding coloration as a signal for mate selection: not such a bright idea after all?

Breeding coloration is phylogenetically widespread in lizards and known to influence mate choice in both sexes. Female breeding coloration (bright yellow, orange, or red) is rare, yet associated with an increase in hormone levels and a change in behavior. The role of female breeding coloration as a signal for mate selection by males varies considerably among lizard species. In some species breeding coloration signals female receptivity and is an attractant for mating, whereas in others it signals courtship rejection by gravid females. We used long-nosed leopard lizards (Gambelia wislizenii) to tested three hypotheses proposed for the role of female breeding coloration and its influence on mate selection by males. We conducted experiments on lizards that lacked or exhibited breeding coloration. Pairs of lizards were introduced in a laboratory arena and their behaviors were recorded with a digital video camera. Males attempted to copulate with females regardless of female coloration and male behavior did not differ before and after the development of female breeding coloration. In contrast, females rejected copulation regardless of their own coloration. Experiments using naturally �bright� and �plain� colored females and those in which we manipulated color (via paint or hormone induction) provided similar results. We conclude that, in contrast to other iguanian lizards, female breeding coloration is not a signal used by male leopard lizards in mate-choice decisions. Thus, the role of breeding coloration in leopard lizards remains enigmatic. Future experiments will test whether female breeding coloration is a signal to other females, or whether it conveys an as-yet-undetermined message.