gender differences: nature of nurture?

Of course there are gender differences, but the scale of them and what, exactly, is included within them, is very difficult to measure. You phrase the question as 'nature vs. nurture', but then we're faced with the problem that all the people we have available to test have already been nurtured. If we find that men are, on average, better at spatial awareness tasks*, how can we tell whether this is genetically-determined sexual dimorphism, due to selection for different gender roles; or the result of societal gender differences leading people to act, and thus develop, in different ways?*I don't know whether this has been found - it's an example pulled from the top of my head.ABE: The fact that two meta-analyses differ on a comple subject does not necessarily mean either are biased. And simply pointing out that someone is a feminist is not enough to demonstrate bias in her findings. She may be fiddling things to support her ideas, consciously or subconsciously, but it seems unfair to me to imply bias simply because the results agree with her preconceptions, without even bothering to look at her work.Edited by caffeine, : No reason given.