Men Throwing "Like a Girl": Separating Nature from Nurture
One of the few genuinely large observed differences between men and women involves throwing ability. Men, on average, are much stronger throwers than women. Hence the phrase "throws like a girl."
That we observe a difference, however, tells us nothing about where that difference comes from. Figuring that out is much more difficult than simply measuring difference and sameness. We know that the difference emerges at puberty, suggesting that sheer size might have something to do with it. But the fact that boys and men, on average, get much more practice throwing than women might also play a role. How to test this?
Well, here's one way: compare men and women throwing with their non-dominant hand. Muscle memory doesn't transfer from one side of the body to the other. Accordingly, since most people have a lot of practice throwing only with one hand, comparing the throws of men and women using their non-dominant hand might tell us something interesting.
I don't know that that study has been done, but an enterprising videographer has captured video of a set of men throwing with the "wrong" hand. What I like most about the video is the men's facial expressions. You can see them laughing at themselves, suddenly reduced to a beginner thrower. Though we still don't know how much of it is biological and how much social -- though, this is the wrong question anyway -- it reveals that, no matter what the answer, men's throwing ability is strongly related to practice.