Some differences are more different than others

Across analyses spanning 122 attributes from more than 13,000 individuals, one conclusion stood out: instead of dividing into two groups, men and women overlapped considerably on attributes like the frequency of science-related activities, interest in casual sex, or the allure of a potential mate’s virginity.

from: "The Tangle of the Sexes" 20 April 2013

The sexes have more in common than in difference, but that doesn't stop us from using sex as one of the key organizing structures of our society. Why do some difference matter so much more than others? What is at stake when we hold so fast to certain definitions that weight certain differences so heavily? Can you think of other cases where humans think very differently about groups that actually share more in common than they differ?