Meeting Abstract

P2.13  Monday, Jan. 5  Courtship pheromones modulate female behavior in a plethodontid salamander VACCARO, EA*; HOUCK, LD; Oregon State University; Oregon State University vaccaroe@science.oregonstate.edu

Female sexual receptivity is a behavior at the crux of mechanistic and evolutionary perspectives of reproductive behavior. Recent work addressing receptivity has established that plethodontid salamander courtships show a reduced time to insemination when the female has received male pheromone. A reproductive Plethodon shermani male has a mental (chin) gland that produces proteinaceous courtship pheromones, and all 26 species in its clade employ the same method of pheromone delivery: the male taps his mental gland on the females nares. Pheromones enter the females nasal cavity and are shunted laterally to the vomeronasal organ (VNO). This VNO-initiated pathway likely transmits pheromonal information to sites in the brain known in other vertebrates to be involved in endocrine regulation and enhancement of sexual behavior. I investigate three candidate mechanisms by which male pheromones may augment female receptivity: 1) by influencing a non-specific state of either stimulation or placidity, 2) by enhancing a central state of sexual motivation, or 3) by affecting specific sensorimotor integration mechanisms in individual sensory modalities. Females treated with pheromone are assayed for enhanced response to visual and olfactory cues (both male- and food-related), as well as differences in heart rate, general locomotor activity, startle response, and foraging activity. By investigating the proximate aspects of a signal-response system, this study ultimately may provide insights into how the perception of a chemical signal can induce a specific change in behavior.