September 29 2009

12:00 154 BSRB

Ecolunch: Catalina Estrada
Integrative Biology, University of Texas at Austin

The Chemistry of Rejection: Evolution of Antiaphrodisiac Pheromones in Butterflies


Intraspecific communication, particularly in a sexual context, is crucial for successful reproduction, and to maintain species integrity.
An important component of the sexual communication system of several insect groups are antiaphrodisiac pheromones, chemicals that reduce the attractiveness of females to subsequent courting males. Because these signals are transferred to females by males during mating, they constitutes one of the mechanisms by which males control female remating rates, and thus, avoid sperm competition. Despite these pheromones being very influential in the reproductive success of male and female insects, little is known about their evolutionary patterns. I will show the results of a comparative analysis of antiaphrodisiacs in Heliconius butterflies. I evaluated how the incidences of visual mimicry and clade-specific mating systems in this genus of toxic butterflies have influenced the evolution of these chemical signals. I did not find any evidence for the influence of mimicry on the chemical composition antiaphrodisiacs. Instead, this study revealed that they have changed in the direction expected under the influence of male-male competition over mating. This suggests that the lack of female control over their production and release can result in sexual conflict.











































































































































































































































































































































































































































































































































































































this is idtest: