The gay reproductive advantage

I recently spotted an interesting article about homosexuality in The Economist. The article describes a new theory which tries to explain why the genes that cause homosexuality have survived in the population. If you think about this it's a bit of a mystery, because genes that make parenthood less likely should gradually eliminate themselves from the gene pool over the long periods of time, so the genetic expectation is that gay people shouldn't exist. However, the new idea is that the genes that make people gay also confer reproductive advantages as long as they do not push the individual possessing them all the way to homosexuality.

For example, apparently personality tests show that gay men rank higher than straight men in standardised tests for agreeableness, expressiveness, conscientiousness, openness to experience and neuroticism. Further data suggest that having a more feminine personality might indeed give a heterosexual male an advantage, because women can be attracted to those with feminine traits such as tenderness, considerateness and kindness, because such men make better carers and providers.

For me, this theory has a ring of truth about it. After all, in my experience, it's not uncommon to hear single women say that all the men they fancy are either already married or gay!