Last week, gay-rights activists led a protest against research being done on sheep at Oregon State University. Andrew Sullivan reports:
The researchers have been adjusting various hormones in the brains of gay rams to try to see if they can get them to be interested in the opposite sex. The indifference of many rams to otherwise attractive and fertile ewes is a drag on sheep-breeding, it seems. We don’t have any peer-reviewed studies yet, but reports of success in manipulating the sexual behaviour of some rams have led to an outcry.
Sullivan is worried that this research will lead parents to start aborting their homosexual infants. (He presupposes that we will one day have a genetic test for homosexuality.)
We already have widespread gender-selective abortion, with fewer and fewer girls being born in the developing world. And most parents across the globe are far more hostile to the idea of a gay child than of a daughter. Tests that could infer even a slightly higher probability of homosexuality in foetuses could lead to the equivalent of a “final solution” to the existence of gay people — the dream of bigots for millenniums.
Obviously, this nightmarish scenario won’t happen anytime soon. Despite the best efforts of geneticists, there is virtually no evidence of a “gay gene”. Homosexuality is a complicated phenotype, and is clearly not reducible to a short script of DNA. (Sullivan uses Down Syndrome as an example of a phenotype that has been subject to “selective abortion”. Needless to say, trisomy is much easier to detect than a trait like homosexuality, which is most likely encoded for by dozens, if not hundreds, of different genes working in concert with the environment.)
But let’s play devil’s advocate, and imagine a world where homosexuality has been selected against. My guess is that such a civilization would be an uncivil nightmare, a Hobbesian dystopia. Last summer, I profiled the theories of Joan Roughgarden, an evolutionary biologist at Stanford. She has constructed a plausible theory about the adaptiveness of homosexuality:
So how might homosexuality be good for us? Any concept of sexual selection that emphasizes the selfish propagation of genes and sperm won’t be able to account for the abundance of non-heterosexual sex. All those gay penguins and persons will remain inexplicable. However, if one looks at homosexuality from the perspective of a community, one can begin to see why nature might foster a variety of sexual interactions.
According to Roughgarden, gayness is a necessary side effect of getting along. Homosexuality evolved in tandem with vertebrate societies, in which a motley group of individuals has to either live together or die alone. In fact, Roughgarden even argues that homosexuality is a defining feature of advanced animal communities, which require communal bonds in order to function. “The more complex and sophisticated a social system is,” she writes, “the more likely it is to have homosexuality intermixed with heterosexuality.”
So here’s my hypothesis: if you select against homosexuality in a biological community, you will also be selecting against our instinct for solidarity. The same genes that give rise to gayness might also give rise to cooperation. When scientists create a population of all heterosexual sheep – this would be a boon to ranchers, since a high percentage of male sheep are gay – they will find that their sheep are now more violent as well.
The truth of the matter is that homosexuality is clearly an adaptive trait. It has been documented in more than 450 different species. As Roughgarden points out, “a ‘common genetic disease’ is a contradiction in terms, and homosexuality is three to four orders of magnitude more common than true genetic diseases such as Huntington’s disease.” Selecting against homosexuality isn’t just immoral and unethical: it’s also just a terrible idea, driven by bad biology.
Note: Sullivan has an scientific update on his column. (The original reporting on this was rife with errors.) Thanks, Larry.