Self-Referencing as a Universal Mechanism Promoting Polyandry in Insects

Board Of Trustees Of Illinois State University, Normal IL

Investigators

Abstract

Principal Investigator: Scott Kitchener Sakaluk Proposal Number: IOS-0718140 Project Title: Self-Referencing as a Universal Mechanism Promoting Polyandry in Insects Female animals often mate with many different males, and this behavior has long puzzled evolutionary biologists. However, recent studies have revealed that by mating with more than one male, females secure good genes that enhance the health and survival of their offspring. That being the case, one might expect females to favor novel mating partners over previous mates, and indeed studies of several unrelated species have shown a clear female preference for novel males. But how do females distinguish between novel males and previous mating partners? Earlier work with crickets suggests that females do so by tagging males with their own odors during mating. When a female encounters a former mating partner later on, she need only compare her own scent with that of the male. If she finds that the male has been imbued with her own chemical signature, she can avoid mating with that male in favor of a novel mating partner. This simple form of self referencing could be a widespread mechanism by which females of diverse animal species maximize the diversity of their mating partners. The proposed research focuses on cuticular hydrocarbons (CHCs) as the basis of chemosensory self-referencing. CHCs are fat molecules abundant on the surface of the insect cuticle; they often play an integral role in insect communication. CHC profiles of females will be manipulated to see if females'' aversion to previous mates can be experimentally abolished. The reliance of females on chemical cues to identify previous mates will be examined by chemically disabling cricket contact chemoreceptors. Behavioral tests will be employed to determine how long self-referent chemosensory cues persist, and to what extent they are masked when males are imbued with odors of other females. Not only will these studies help establish a potentially universal mechanism of mate recognition in insects, they could also potentially lead to the identification of chemical compounds that inhibit female mating behavior, furnishing a relatively safe, but effective means of biological control of insect pest species. The proposed research will provide training to a postdoctoral fellow and several undergraduate and graduate students, and will help redress the current under-representation of women in science. Graduate students and the PIs will continue their participation in ongoing programs designed to enhance elementary school teachers'''' training in science and to mentor female high school students.