I saw this on BoingBoing. I’m not sure the theory is well-established or supported, but damn does that ever make a lot of sense. It has some other implications, including the notion that, at least in the context of the juggernaut that is overpopulation, these genes are good when they manifest as homosexuality but not when they manifest as heterosexuality.
Basically, what I’m saying is what you already knew from popular depictions of gays and lesbians: They are amazing people who are the products of excellent genes.