Meeting Abstract

P2.170  Monday, Jan. 5  Effect of incubation temperature on the morphology and endocrinology of the reproductive tract of a turtle with temperature-dependent sex determination. THERRIEN, Corie; WIBBELS, Thane*; University of Alabama at Birmingham twibbels@uab.edu

The differential fitness hypothesis suggests that temperature-dependent sex determination could be advantageous because it allows the matching of sex to fitness. The current study addressed the potential physiological mechanism by which temperature-dependent sex determination (TSD) might affect fitness. The effects of specific incubation temperatures on the morphology and endocrinology of the gonads and reproductive tracts were examined in the red-eared slider turtle (Trachemys scripta). Gonads and reproductive tracts were compared between late-stage embryos incubated at temperatures that produced either 1) all females, 2) mostly females, 3) mostly males, or 4) all males. The gross morphology and histology of the reproductive tracts of these four groups were compared and the testosterone and estradiol-17B content were measured. The results indicate significant variation between the gonads of females incubated at different temperatures and moderate differences in the males. The results show morphological and physiological variation in the gonads of from turtles incubated at different temperatures. These findings provide a potential mechanistic basis for the differential fitness hypothesis. Further, the results provide insight on optimal incubation temperatures for turtle conservation programs that artificially incubate eggs.