What the Humble Fruit Fly Can Teach Us About Sex

This piece was originally published on the Blowfish Blog.

I love science.

From the vaunted Pharyngula science blog comes this hilarious and enlightening news of mutant bisexual fruit flies.

(As they say on Mythbusters: "Warning: Science Content." Lots of it, if you read the whole linked story.)

The gist, in case you don't feel like reading all the darned neuroscience: In a particular species of fly, there is an occasional genetic variation -- I'm trying not to call it a mutation, that's such a judgmental word -- that causes them to behave bisexually. It causes some females to try to initiate sex with other females; it causes some males to wait for other males to initiate courtship; and it causes some males to attempt, equally, to initiate courtship with both females and males.

They will, to be blunt, fuck anything that flies.

And researchers haven't just identified the existence of the mutation -- excuse me, the variation. They haven't just identified the gene that causes it, even. They've identified the specific neurological mechanism.

(Hence the science content.)

Now, PZ Myers, Pharyngula blogger of song and story, warns that we shouldn't jump to conclusions about what this might mean for human sexuality. And I think he's right to do so. Human beings are rather more complex than fruit flies. And our sexuality is, to put it mildly, a lot more complex. Fruit flies don't, for instance, get hot for spanking, for latex, for women in seamed stockings, for men in seamed stockings, for bits and saddles, for stuffed animals, for cartoon characters, for curly-haired brunettes who look like Bette Davis.

So the fact that sexual orientation is genetically determined in fruit flies doesn't prove, even a little bit, that it's genetically determined in humans.

But it does tell us something about humans, and human sexuality.

It doesn't tell us that our sexual orientation is genetically determined, or even genetically influenced.

But it tells us that it might be.

It tells us that it's not ridiculous to consider the possibility.

It tells us that, at least in some animals, a tendency towards heterosexuality or bisexuality -- and arguably homosexuality, if you think about those male flies waiting coyly for the other male flies to make the first move -- is genetically determined. Entirely, as far as anyone can tell. And therefore, it tells us that it's not out of the question to think that it might be genetically determined -- at least partially -- in other animals as well.

Including humans.

And this is an important message: not just for the homophobic right wing, but for the queer-theory crowd as well.

There are queer theorists and activists who would be delighted to learn that sexual orientation is genetically determined at birth. For no other reason, they think it makes the civil rights battle easier to fight if they can play the "We were born this way" card. There are queer theorists and activists who think, not only that we might be born queer, but that we definitely are, and that the case is closed.

And there are queer theorists and activists who would be appalled to learn that orientation is determined by genetics. Even partially determined by genetics. Even a little bit determined by genetics. There are queer theorists and activists who actively resist this idea, who see it as dangerous and oppressive. There are queer theorists and activists who not only disagree with this theory, but who think that we should not even be considering it.

But here's the thing.

We shouldn't be thinking about this question on the basis of which answer we would like to be true.

We should be thinking about this question on the basis of which answer is true. We should be thinking about this question on the basis of which answer is supported by the evidence.