[LaGrange]

"more men die in the military because more men join it"

Ooh, what a great example that women are (generally) encouraged to take less risks, while men are (generally) encouraged to take more risks.

Not that some brain function differences are impossible, but assumptions about brain function seem more risky (sorry) than assumptions about cultural conditioning. Until we can get an ethical double-blind study on a large group of women with perfectly controlled upbringing, or at least a good study including some hypothetical culture that encourages women to take risks (not the same as matriarchal), I think it's better to assume cultural differences.