Might societal acceptance of homosexuality drive it extinct?


The precise causes of homosexuality are not completely clear, but most scientists agree that there is a genetic component, perhaps 35% for gay men and about half that for lesbians. There is unlikely to be a single gene that makes people gay, but there may be some genetic variation that increases the probability of becoming gay, or is a necessary precondition but also requires a certain environment (e.g. intra-uterine). (I have written previously on why natural selection could produce homosexuality, counter-intuitive as that sounds.)

In any case, the simple fact of genetic variation associated with homosexuality means that natural selection can act on it, and this has a major and paradoxical implication. The more biological children of gay people, the more transmission of these genes, and the more gay people there are. The less biological children of gay people, the fewer gay people there will be in subsequent generations. But in what societies do gay people have the most biological children? Almost certainly those societies that forbid homosexuality, forcing gays to marry and have children. Modern societies with liberal social policies will likely see many gay couples adopting, but fewer having biological children. Over time, this means that societal acceptance of homosexuality might actually drive it extinct, or nearly so. Unfortunately, natural selection in this case will function such that every society will achieve, long-term, the opposite of what it wants. Read the rest of this entry »