I theorize a primary factor is the fact that women tend to be more social than men. Lots of exposure to a large social group during one's upbringing can have a strong effect the extent of your learning. Mens' social groups tend to be more disparate, and lead the overall society to favor a wider range of skill sets, from big dumb brute to brilliant strategist. Another factor could be the act of childbirth, and the raising of children. Really stupid women would have less evolutionary success in raising healthy offspring, while, at the same time, very high intelligence was not important to feed and clothe a child.
I love summer, and hate winter; Summer is full of life, I love being able to walk outside in shorts and be comfortable, and I love the feeling of the sun on my skin. Heat doesn't really bother me, but I get cold really easily.
Explain cognitive dissonance.