Our lab is working with 2 faculty from the Reproductive Sciences Program on a project examining the behavior of inter-sex individuals. We generate female (XX chromosome) sheep with varying degrees of virilization for the purpose of studying the developmental components of the hypothalamic/pituitary/gondal axis.

We also have created XY sheep with varying amounts of masculinization blocked. They are ideal animals for examining the effects of intersexual external and internal phenotypes on behavior. Such work has only been done in the past with completely virilized rodents and a small number of studies with primates. These animals, like humans, are born with mild, moderate or severe external virilization. Depending on whether external virilization was created by testosterone or DHT exposure, the hypothalamic function is similarly partially virilized, or not virilized at all. Similarly, a lack of masculinization (due to flutamide exposure) should not prevent males from showing male typical behaviors since the brain is thought to be masculinized by estrogen.

We have collected two years of longitudinal data on two cohorts of lambs. We have collected brains from several experimental groups to determine the extent to which behavioral differences correlate with differences in brain activation by sex-related stimuli, and basic organization of the extended amygdala.

We are finding that early behavioral interactions predict adult behaviors in some interesting ways. Androgen exposure does not control the extent of male behavior exclusively.