Why sex?

Continuing my springtime frolicsome mood, a paper in this week's Nature shows that sex is good for us. Well, not necessarily us as individuals, but as a population. This has actually been a longstanding argument in evolutionary biology—sex is risky, it's hard work, and it is prone to failure. Why not just have women reproduce asexually, and bloom into pregnancy automatically as soon as they hit puberty? That would be much more efficient. Sex also has the problem of breaking up good gene combinations; as you may or may not know, my wife is perfect, but in order to reproduce, she has to water down her flawless genes by combining them with those of a lesser member of the species, me. And then of course, there's the problem of us males. We could instantly double the reproductive capacity of our population if all males were equipped with uteruses and could also bear children. It's a weird, weird system.

So why do we bother with sex? Why aren't we being displaced right now by more fecund asexual populations?

Continue reading "Why sex?" (on Pharyngula)