Meeting Abstract

P2.171  Monday, Jan. 5  Reproductive and endocrine responses to breeding density in laboratory-housed green anole lizards ADAMS, Amber L*; LIGON, Day B; LOVERN, Matthew B; Oklahoma State University; Missouri State University; Oklahoma State University amber.l.adams@okstate.edu

Previous studies have demonstrated myriad effects of social environment on reproductive physiology, and often these effects are communicated from mother to offspring via hormone exposure. A preliminary study in 2007 suggested that female green anoles lay fewer eggs and have higher corticosterone levels when breeding densities are high. In the present work we follow up and expand upon these results. Breeding females were housed in cages with either one male (low density) or one male and three additional females (high density) to evaluate the effects of breeding density on reproductive effort and plasma and yolk testosterone (T) and corticosterone (CORT) concentrations. All animals were maintained under standard breeding conditions for ten weeks and nest boxes were checked daily for eggs which were frozen for subsequent yolk steroid analyses. Blood samples were collected from all lizards at the end of the study. We found that breeding density had no affect on body condition for either males or females, although body condition declined overall for males. We also found that, consistent with last year, although there was no treatment effect on egg mass, females in low density environments produced significantly more eggs than females in high density environments. Plasma and yolk T and CORT levels will be analyzed by radioimmunoassay to determine how males and females responded hormonally to breeding density and whether females differed in their yolk steroid content as a result of treatment. Such effects, if present, would demonstrate environmental effects on reproductive physiology as well as the opportunity for mothers to communicate information about the environment to their offspring via hormone exposure.