NYT: As Barriers Disappear, Some Gender Gaps Widen

In the NYT's Science section on Monday,

When men and women take personality tests, some of the old Mars-Venus stereotypes keep reappearing. On average, women are more cooperative, nurturing, cautious and emotionally responsive. Men tend to be more competitive, assertive, reckless and emotionally flat. Clear differences appear in early childhood and never disappear.
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For evolutionary psychologists, the bad news is that the size of the gender gap in personality varies among cultures. For social-role psychologists, the bad news is that the variation is going in the wrong direction. It looks as if personality differences between men and women are smaller in traditional cultures like India’s or Zimbabwe’s than in the Netherlands or the United States. A husband and a stay-at-home wife in a patriarchal Botswanan clan seem to be more alike than a working couple in Denmark or France. The more Venus and Mars have equal rights and similar jobs, the more their personalities seem to diverge.
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These findings are so counterintuitive that some researchers have argued they must be because of cross-cultural problems with the personality tests. But after crunching new data from 40,000 men and women on six continents, David P. Schmitt and his colleagues conclude that the trends are real. Dr. Schmitt, a psychologist at Bradley University in Illinois and the director of the International Sexuality Description Project, suggests that as wealthy modern societies level external barriers between women and men, some ancient internal differences are being revived.

The biggest changes recorded by the researchers involve the personalities of men, not women. Men in traditional agricultural societies and poorer countries seem more cautious and anxious, less assertive and less competitive than men in the most progressive and rich countries of Europe and North America.

To explain these differences, Dr. Schmitt and his collaborators from Austria and Estonia point to the hardships of life in poorer countries. They note that in some other species, environmental stress tends to disproportionately affect the larger sex and mute costly secondary sexual characteristics (like male birds’ displays of plumage). And, they say, there are examples of stress muting biological sex differences in humans. For instance, the average disparity in height between men and women isn’t as pronounced in poor countries as it is in rich countries, because boys’ growth is disproportionately stunted by stresses like malnutrition and disease.

I remember reading somewhere that gender-specific dysmorphic disorders such as anorexia and the Adonysis complex (ie body building syndrome) tend to be more common in relatively egalitarian societies and groups. Otherwise put, the more men and women are socially equal, the more they try to differentiate each other physically by accentuating their secondary sexual characteristics. I wonder how that all ties in...