we gays did not reproduce in as high a number as straights, if at all.
Here’s a look at some research on the topic about gay men. Now they need to do some studies about WASOTSI women!
http://www.psychologytoday.com/articles/index.php?term=20080420-000003&page=1Finding the Switch
Homosexuality may persist because the associated genes convey surprising advantages on homosexuals' family members.
By: Robert Kunzig
If there is one thing that has always seemed obvious about homosexuality, it's that it just doesn't make sense. Evolution favors traits that aid reproduction, and being gay clearly doesn't do that. The existence of homosexuality amounts to a profound evolutionary mystery, since failing to pass on your genes means that your genetic fitness is a resounding zero. "Homosexuality is effectively like sterilization," says psychobiologist Qazi Rahman of Queen Mary College in London. "You'd think evolution would get rid of it." Yet as far as historians can tell, homosexuality has always been with us. So the question remains: If it's such a disadvantage in the evolutionary rat race, why was it not selected into oblivion millennia ago?
Twentieth-century psychiatry had an answer for this Darwinian paradox: Homosexuality was not a biological trait at all but a psychological defect. It was a mistake, one that was always being created anew, in each generation, by bad parenting.
<snip>
It turns out that parents of gay men are no better or worse than those of heterosexuals. And homosexual behavior is common in the animal kingdom, as well—among sheep, for instance. It arises naturally and does not seem to be a matter of aloof rams or overbearing ewes.
<snip>
More is known about homosexuality in men than in women, whose sexuality appears more fluid. The consensus now is that people are "born gay," as the title of a recent book by Rahman and British psychologist Glenn Wilson puts it. But for decades, researchers have sought to identify the mechanism that makes a person gay.
<snip>
But we know gayness is not entirely genetic, because in pairs of identical twins, it's often the case that one is gay and the other is not. Studies suggest there is a genetic basis for homosexuality in only 50 percent of gay men.
<snip>
No one has yet identified a particular gay gene, but Brian Mustanski, a psychologist at the University of Illinois at Chicago, is examining a gene that helps time the release of testosterone from the testes of a male fetus. Testosterone masculinizes the fetal genitalia—and presumably also the brain. Without it, the fetus stays female. It may be that the brains of gay men don't feel the full effects of testosterone at the right time during fetal development, and so are insufficiently masculinized.
But if that gene does prove to be a gay gene, it's unlikely to be the only one. Whatever brain structures are responsible for sexual orientation must emerge from a complex chain of molecular events, one that can be disrupted at many links. Gay genes could be genes for hormones, enzymes that modify hormones, or receptors on the surface of brain cells that bind to those hormones. A mutation in any one of those genes might make a person gay.
<snip>
By interfering with the masculinization of the brain, gay genes might promote feminine behavior traits, making men who carry them kinder, gentler, more nurturing—"less aggressive and psychopathic than the typical male," as Rahman and Wilson put it. Such men may be more likely to help raise children rather than kill them—or each other—and as a result, women may be more likely to choose them as mates.
<snip>
Camperio and his colleagues compared the family trees of gay men to those of straight men, and confirmed that homosexuals had more gay male relatives on their mother's side than on their father's side—which suggests an X-linked trait. But the Italian researchers also found something more intriguing: Compared with the straight men, the gay men had more relatives, period.
<snip>
Camperio recalls. "I explained to her that we found out that homosexuals come from large families. I told her that there is an inheritance from the mother—she's giving the homosexual genes to her son. I said, 'This is impossible—how can they be surviving?'"
His daughter, 15, replied, "But Dad, did you check if this factor that makes sons homosexual is not the same factor that makes the mother produce more children and have big families?"
<snip>
For every older brother a man has, his chances of being gay go up by around a third. In other words, if you have two older brothers, you're nearly twice as likely to be gay—regardless of whether the older brothers are themselves gay. It is not possible to explain that as an effect of genetics.
<snip>
But in another study, Bogaert found that it was only biological older brothers that contributed to the effect. Men who grew up with older stepbrothers or adopted brothers—brothers born of different wombs—were no more likely to become gay...
In other words, the effect could not be explained through upbringing.
<snip>
Most recently, Bogaert, Blanchard, and their colleagues have found that older brothers increase the likelihood of homosexuality only in men who are right-handed—even though left-handed men are more likely to be gay in general. "We don't really know what that means," says Bogaert.
<snip>
So how do the pieces fit together? So far, they don't. Rather, they exist side by side. "There is no all-inclusive explanation for the variation in sexual orientation, at least none supported by actual evidence," says geneticist Alan Sanders of Northwestern University. It's one of the most consistent themes to emerge from the literature on homosexuality: the idea that there are many different mechanisms, not a single one, for producing homosexuality.
<snip>
The biggest gap in the science of homosexuality concerns lesbians: Much less research has been done on them than on men. That's because women's sexuality seems to be more complicated and fluid—women are much more likely to report fantasizing about both sexes, or to change how they report their sexual orientation over time—which makes it harder to study. "Maybe we're measuring sexual orientation totally wrong in women," says Mustanski. Rahman and Wilson suggest that lesbianism might result from "masculinizing" genes that, when not present to excess, make a woman a more aggressively protective and thus successful mother—just as feminizing genes might make a man a more caring father.
Right now, there is no one all-inclusive solution to the Darwinian mystery of why homosexuality survives, and no grand unified theory of how it arises in a given individual.
Homosexuality seems to arise as a result of various perturbations in the flow from genes to hormones to brains to behavior—as the common end point of multiple biological paths, all of which seem to survive as side effects of various traits that help heterosexuals pass along their genes. 
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