Brokeback Mutton

By William Saletan
Sunday, February 4, 2007

Just over the Montana border, closeted in their own private Idaho, the gay sheep were getting it on.

Well, it's not exactly private. They were doing it in front of scientists at the U.S. Sheep Experiment Station. The scientists arranged the trysts. It's called "sexual partner preference testing."

According to an article by researchers involved in the project, here's how it works. In a 15-by-10-foot "arena," a young ram is offered four choices: two ewes in heat, and two rams. "The four stimulus animals are restrained in stanchions so that they can only be approached from the sides and rear." For 30 minutes, the unrestrained ram does as he pleases -- and the scientists keep score.

A bare majority of rams turns out to be heterosexual. About one in five swings both ways. About 15 percent are asexual, and seven to 10 percent are gay.

Why so many gay rams? Is it too much socializing with ewes? Same-sex play with other lambs? Domestication? Nope. Those theories have been debunked. Gay rams don't act girly. They're just as gay in the wild. And a crucial part of their brains -- the "sexually dimorphic nucleus" -- looks more like a ewe's than that of a straight ram. Gay men's brains similarly resemble those of women. Charles Roselli, the project's lead scientist, says that such research "strongly suggests that sexual preference is biologically determined in animals, and possibly in humans."

Roselli's interest is in the science. He figured the political upshot, if any, would be gay-friendly. After all, surveys show that if you think homosexuality is biologically determined, you're less likely to be anti-gay.

Roselli didn't just prove that homosexuality in rams is natural. He tried to engineer it. In a 1999 grant application, he proposed to determine whether male-oriented "preference behavior can be artificially produced in genetic male sheep" by depriving male lamb fetuses of estrogen stimulation. Seven months ago, he reported that the experiment failed. The point wasn't to promote homosexuality. The point was to learn what causes it.

You'd expect conservatives to demand that the National Institutes of Health stop funding this research. But if you figure out how to make sheep gay, maybe you could figure out how to make them straight. And maybe you could do the same to people.

Roselli studies hormones, brains and behavior at Oregon Health and Science University, a medical institution. But Fred Stormshak, his collaborator, is an animal scientist affiliated with Oregon State University, which focuses more on agriculture and economics. Gay rams are "a costly problem for sheep producers because breeding rams are worth $300 to $500 each," Stormshak said in OSU's agricultural newsletter a decade ago. "Outwardly, there is no way to tell whether a ram is male-oriented, so the producer runs the costly risk of buying an animal that will never produce any offspring."

Identifying gay rams wasn't enough. In 2000, Stormshak described an attempt to "alter" them. The idea was to "enhance their sexual behavior or performance" by making them act like straight rams. Three years later, Roselli told an OHSU committee that "information gained about the hormonal, neural, genetic, and environmental determinants of sexual partner preferences should allow better selection of rams for breeding and as a consequence may be economically important to the sheep industry." OSU President Ed Ray says the research "may define biological tests that can be used to identify" gay or asexual rams, "thus eliminating their use for general breeding purposes."

Notice the lack of animus. Breeders don't care whether rams are gay or simply unmotivated. All that matters is "performance." And when Ray talks about "eliminating" such rams from breeding, he leaves open the possibility of their grazing happily into old age. But you can smell the slaughterhouse.

Which brings us to the animals whose breeding we really care about: our children.

Passing on genes is life's deepest drive. You don't just want kids. You want grandkids. An Israeli woman, with court approval, is using her dead son's sperm to inseminate a stranger. I know a man whose future mother-in-law put him through a fertility test before approving the marriage. Then there are parents who pressure their adult children to marry and procreate. In a survey, 73 percent of Americans said they would be upset to learn that their child was gay. To many parents, "I'm gay, Mom" means "No grandkids."

Roselli offers evidence that human homosexuality is linked to biological conditions, some of them genetic. If he figures out how to manipulate sexual orientation in sheep, will others try to manipulate it in humans? Doctors used to "treat" homosexuality with hormone injections. Some still do. This idea failed miserably in adults, but it might work in fetuses. And if we can't engineer sexual orientation, maybe we can select it. In Asia, millions have used modern tests to identify female fetuses so they could be aborted. If we learn how to recognize gay brains in development, look out.

The more likely path is gentler. Science will gradually convince us that sexual orientation is innate, more like skin color than character. Condemnation of homosexuality as a sin will subside, and we'll turn to two biological differences between race and sexual orientation: Homosexuality defies the aspiration to procreate with your mate, and it's easier to isolate and alter in embryonic development. We may come to view homosexuality as we do infertility -- as a disability. The rhetoric of "acceptance" will shift from liberals to conservatives. We'll inoculate our children against homosexuality out of love, not hate.

The sheep researchers didn't intend anything like this. But they didn't foresee the uproar over their work, either. People for the Ethical Treatment of Animals has tried to quash their research, depicting them as bigots. PETA, like President Bush, thinks that bad ideas come from bad people, and you must stamp out the whole lot.

But bad ideas, such as communism and eugenics, are usually well-intended ideas that turn bad along the way. What we do with the biological truth about homosexuality isn't written in our genes. It's up to us.

William Saletan covers science and technology for Slate, the online magazine at

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