from "Born that way" theory
By Linda Ames Nicolosi
Nov. 7, 2002 -- A study announced November 4th by a research team at Oregon Health Sciences University has investigated the brain structures of a group of rams that mate only with other rams.
Working at the US Department of Agriculture's Sheep Experiment Station in Idaho, the study's lead researcher, Dr. Charles Roselli, observed that some rams only mount other rams, not ewes. They don't actually pair-bond with these other rams like normal rams do with ewes. However, their sexual attraction is strictly same-sex.
Intrigued by this anomaly, the scientists dissected the "gay" rams' brains and found that their hypothalamus was female-like in size. Roselli believes that abnormal prenatal hormonal exposure of these rams' brains may have caused them to develop in a sex-atypical manner.
"We are not trying to explain human sexuality by this study," Dr. Roselli cautioned. "Whether this is a big component of what contributes in humans, it's still debatable."
This "gay sheep" study follows another recent study on frogs which suggests that prenatal hormonal abnormalities can distort the normal growth of tadpoles by feminizing them if they are exposed to certain environmental toxins during early development. Atrazine, a common weedkiller, was implicated in that study as the apparent cause of feminized or hermaphroditic adult frogs (frogs with both male and female sex organs).
Human sexuality is known to be much more complex that animal sexuality: humans pair-bond and develop a romantic sensibility, rather than simply responding on a physiological level to mating calls and sex odors. Their psychological bonding experiences--most critically, with same-sex parents and peers--then solidify their gender identity and sexual orientation.
But even though our sexual identity is more than a strictly biological phenomenon, studies such as these do provide an intriguing window into the mystery of what may "open the door" into homosexuality for at least some men and women--as psychiatrist Jeffrey Satinover says--while that same door remains relatively closed to other people.
Further information on this study is reported at