>>In other words, I doubt many gay men were procreating with straight women in the past. To me, that suggests they would be bisexual men, not gay. Few people, if any, would be thinking about the survival of the human race if they didn't procreate. People had kids for personal reasons: kids worked long hours, whether on a farm or elsewhere, to provide cheap labor to support their families; they were also expected to help support their parents in their old age (still true in many countries); and they were a bit of insurance in case disease killed some of them, which was common.
I admit it. I've always just put gay and bisexual in the same boat. You're saying I'm wrong?!?!?! Hmm. Nothing like learning something new. I've heard of hetero men going to prison and doing homo stuff then getting out and returning to hetero. Can't it work with homo men needing to increase the family using women and then doing homo stuff on the side? I was not expecting this conversation!
They may not have been thinking in terms of the human race but like you said in terms of family, tribe, nation. I'd assume family would override almost anything.