Meeting Abstract

19.4  Sunday, Jan. 4  Brain regions associated with female preference behavior in a poecillid fish, Xiphophorus nigrensis WONG, R.Y.*; CUMMINGS, M.E.; University of Texas at Austin; University of Texas at Austin ryan.wong@mail.utexas.edu

Individual variation in female preferences for a mate can be seen in a wide range of taxa. Yet little is known about the underlying proximate mechanisms behind this variation despite the potential important evolutionary consequences. Here we present our findings on brain regions that may underlie female mate choice behavior in a poecillid fish, Xiphophorus nigrensis. Females (n=30) were subjected for 30 min. to one of three treatment conditions in a classic dichotomous choice setup: mate choice, a female social control, and an asocial experimental handling control. We recorded the association time and female behaviors exhibited during the trials in order to assign preference and activity scores. After the behavior trial, females were immediately sacrificed, cryosectioned onto serial series, and prepped for nonradioactive in situ hybridization. Through optical density measurements, we measured the localized expression of a neural activity marker (egr-1) and two previously identified candidate genes for mate preference behavior (neuroserpin & neuroligin-3) in several brain nuclei. Utilizing the individual variation in female preferences in this species, we show preliminary evidence that the area dorsomedialis (Dm) and area dorsolateralis (Dl) of the telencephalon have a significant positive relationship between optical density and preference only in mate choice conditions. This suggests that these telencephalic nuclei may play a more important role in preference behavior.