I know of that "Why Beautiful People Have More Daughters" book, and I think that's also true for rich people. Therefore your friends must be poor and ugly ;)
Anyway, we know that masculinity has been favored in men while femininity has been favored in women. So more masculine men had more kids and more feminine women did. A really masculine man might end up having a masculine daughter, and that's not going to work as well.
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So there's some pressure on divergence, but divergence is hard because usually traits affect both sexes of offspring and the male and female strategies are in tension. Maybe something could happen to sperm ratios or something, but I think these effects are all pretty small.
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