The answer to this question has been staring us in the face for millennia, but there are still many who believe that homosexuality is some sort of fetish or learned behavior. A recent study published in the Proceedings of the National Academy of Sciences (a peer-reviewed scientific journal) reveals evidence that homosexuality (at least in men) may be caused by womb-related conditions:

Professor Anthony Bogaert from Brock University in Ontario, Canada, studied 944 heterosexual and homosexual men with either “biological” brothers, in this case those who share the same mother, or “non-biological” brothers, that is, adopted, step or half siblings.

He found the link between the number of older brothers and homosexuality only existed when the siblings shared the same mother.

Other recent research points to certain genetic factors that may determine sexual orientation. There may not be one single cause of homosexuality in men, but it seems damned obvious at this point that it is not a “choice”.