It always seemed to me that this apparent divergence might have more to do with ambition or society than with brainpower. The physical differences between male

It always seemed to me that this apparent divergence might have more to do with ambition or society than with brainpower. The physical differences between male and female brains are pretty subtle, hormonal and social differences are much more pronounced. And if there were single gene changes for raising or lowering intelligence I expect they would have spread through the population even faster than adult lactase. Though I suppose you could argue that this is happening continuously and that's why we have the Flynn effect, but in that case you wouldn't find the relative IQs of national groups tracking their relative wealth in the way we observe even in response to plainly exogenous factors like Communism in East Germany. I expect that there are some genes that increase IQ but have side effects[1], but I expect most genetic causes of variation in IQ rest on combinations of genes. [1]http://www.iovs.org/content/45/9/2943.full http://www.iovs.org/content/45/9/2943.full