The main objective of this proposal is to dissect what part of female mate choice behavior is driven by hormones versus other neural and genomic pathways in the brain. For years, reproductive biologists have understood how hormones influence female willingness to mate. However, we know far less about how hormones influence female choice when selecting between reproductive partners. This study will use a model animal system in sexual selection, the swordtail fish, to identify the neural response during mate choice events and to detect what part of that response is driven by hormones, such as estrogen, and what is hormone-independent. The researchers will build on earlier work in the Cummings lab that has identified candidate genes involved in preference behavior.
The researchers will first conduct a behavioral study that examines the relationship between hormones, candidate gene expression, and preference behavior in a group of swordtail females. The researchers will then test whether specific genes regulate preference behavior independent of hormones by conducting an estrogen-manipulation experiment. Swordtail females will have their estrogen levels blocked or augmented and their preference and gene expression subsequently will be quantified. If mate preference is independent from receptivity, then these manipulations should have little effect on preference behavior or preference-associated gene expression. The results will provide novel insights into the neural and genomic pathways that are specific to choosing mates, and to what degree some of the behavior and/or genomic pathways are under hormonal influence. This innovative study will affect the fields of Animal Behavior, Evolution, and Reproductive Biology. The educational impacts are broad, as the PI integrates this research into her undergraduate classes as well as recruits a number of minority students into her lab to conduct the behavioral and molecular research.
