Social Econ Blog

In comments to one of the posts below, Mark posits a few good hypotheses for the relationship he and some friends noticed between family income and "hotness" among the girls at his high school.

He posits 3 hypotheses:

(1) Girls from wealthier have more resources to enhance their appearance
(2) Man with high incomes may be able to attract more attractive wives (thus improving child genetics ... and I would add the chances that daughters have mothers who can train them to be good at (1))
(3) Men with high incomes are more likely to be attractive themselves (further improving child genetics.

There is an additional complementary explanation to this list that I neglected to pull from the archive yesterday -- oddly, more attractive people are more likely to have daughters:

4) Stephen Dubner links to some wild evolutionary biology research using the National Longitudinal Survey of Adolescent Health which finds that individuals rated more attractive by their interviewers are 36% more likely to have girl for their first child.

According to this news article, "Selection pressure means when parents have traits they can pass on that are better for boys than for girls, they are more likely to have boys. Such traits include large size, strength and aggression, which might help a man compete for mates. On the other hand, parents with heritable traits that are more advantageous to girls are more likely to have daughters."

Beauty is apparently just one "female" trait. Kanazawa has done previous research suggesting that nurses, social workers and kindergarten teachers -- those with "empathic" traits -- also had more daughters than sons. Meanwhile, he found that scientists, mathematicians and engineers are more likely to have sons than daughters.