Meeting Abstract

S1-1.5  Thursday, Jan. 3  Maternally derived yolk steroid hormones in TSD reptiles: A comparison among species and their possible roles in embryonic development ELF, P; University of Minnesota Crookston pelf@umn.edu

Maternally produced hormones deposited in yolk material have been implicated in the sex determination process in oviparous reptiles with temperature-dependent sex determination (TSD). We have investigated several parameters of yolk hormone deposition including initial levels, dynamics during development, individual female effects, and seasonal variation of several of these hormones in various TSD reptiles. We have also measured maternal circulating and yolk levels of these hormones in one viviparous TSD reptile species. Our data indicate some common themes among these species despite differences in TSD pattern and life history. We also have data related to incubation temperature specific differences in utilization of yolk hormones by developing embryos in viviparous and oviparous TSD reptiles. These similarities have implications for the possible role of yolk hormones in the sex determination process and embryonic development.