[Helm]

I wouldn't call this HARD SCIENTIFIC EVIDENCE but yeah, I think some people who claim to be bisexual aren't really biologically urged towards it. Just like a significant part of the people who claim to be gay also have no inherent tendency towards homosexuality. I'm not denying that gay men and women exist, I'm just saying that there are a lot of people, like ziggy said, who pick it up as learnt behaviour, not because they can't help it. People like to pick up labels. I wouldn't be surprized, for example if one were to check a sadomasochist clique only to find that a quantity of the people are aren't really into pain, but rather are so desperate for sex they're willing to do the latex bullshit just so they can get off eventually.

being bisexual makes more sense than being gay from an evolutionary standpoint because it maximizes the chance of one having sex as means to stress-relief while also leaving the chance of mating to create babies ( which is the prime directive and all ) so I guess it would make more sense of people were bisexual than gay. But that's just theorizing.