Very true. But I think that's a spandrel case. Sociobiology evolved for other reasons and as a byproduct offered opportunities for lefties to speculate too.
I've been thinking a bit about 'why' questions lately. Consider these:
1) Why is the sky blue?
2) Why were the rulers of Austria-Hungary named Habsburg?
3) Why is the quantum of action equal to 6.6260693 * 10^-34 J*s?
4) Why does e**(i*pi) + 1 = 0?
5) Why is none of my friends named Bacigalup?
1) gets what we normally think of as a scientific explanation; there's a physical principle behind it (higher frequency light is more scattered by the atmosphere).
2) gets a "how it happened" explanation; you recount the history.
3) isn't incoherent, but we don't know the answer; probably never will know the answer; and I suspect in some real sense it doesn't have an answer. Although of course we can speculate as much as we like.
4) has an analytic answer; you show how the concepts are related.
5) is the oddest; it sort of presupposes that maybe I _ought_ to have at least one friend named Bacigalup. If the question isn't actually senseless, the only possible answer is, I just don't, or that's just the way it is, or some such.
Now. Why is the clitoris of the human female where it is? Which of the above kinds of 'why' question is this?