<Biological Exuberance: Animal Homosexuality and Natural Diversity by biologist Bruce Bagemihl will give you some 800 pages on zoological studies of homosexual behaviors and on the history of naturalists' reporting and suppression of their findings.

I venture to suggest that reported and observed homosexual behavior in humans is higher in large metropolitan areas (areas with high population density) because of the higher levels of all kinds of behaviors in such cosmopolitan areas. There's a reason serfs ran away to the towns: they could get lost in the crowd there. To hide a needle, pick not the haystack but the box of needles.

Behaviors considered weird, strange or immoral tend to be hidden, rationalized, ignored and persecuted in smaller, more parochial communities. Little towns have big closets.

If the community contains subcommunities specifically devoted to a particular type of living (such as religious orders or communes) or if the person is living in isolation (a hermit or "mountain man"), the behavior may be overlooked or accepted as a part of that peculiar way of life.

That didn't work for David Koresh, but then, he wasn't gay. Maybe straight religious extremist genes are something we can identify and control. ...Just kidding.

Regards--
Mary Anne