Cryptic Sexual Conflict in Gift-Giving Insects: Chasing the "Chase-Away"

Board Of Trustees Of Illinois State University, Normal IL

Investigators

Abstract

Lay Abstract of Proposed Research Principal Investigator: Scott Kitchener Sakaluk Project Title: Cryptic sexual conflict in gift-giving insects: chasing the "chase-away" Conventional models for the coevolution of exaggerated male sexual ornaments and female mating preferences posit that females derive material benefits or indirect genetic benefits by preferentially mating with the most conspicuous males. The chase-away sexual selection model, however, suggests that elaborate male sexual displays can arise because they exploit pre-existing biases in females' sensory systems, inducing females to mate in a sub-optimal manner. An essential element of this hypothesis is that such manipulation should quickly lead to female resistance or decreased attraction to male display traits. Although anecdotal evidence in certain taxa appears to provide support for the evolution of female resistance, the hypothesis has not been directly tested. Nuptial food gifts, an integral feature of the mating systems of a wide variety of insects, may be a frequent conduit by which males attempt to influence the mating behavior of females against females' own reproductive interests. Recent work in my laboratory suggests that the food gifts offered by male decorated crickets contain substances that at one time inhibited the sexual receptivity of females, but that females have evolved resistance to these substances. The proposed research seeks to establish the receptivity-inhibiting properties of these food gifts by offering them to females of several non-gift-giving species, and measuring their effect on female fitness. These studies may lead to the identification of male-derived hormonal substances that inhibit female mating behavior, which ultimately could furnish a safe, but effective means of biological control of insect pest species.