towards an etiology of prejudice

It seems that racism/sexism/homophobia/etc/etc/etc are pervasive tendencies in society. I believe that if men hadn't come to dominate women, it would be women who had tried to dominate men. And if light-skinned people hadn't dominated others, someone of another ethnicity/race would have tried to dominate lighter-skinned people.

Caveat #1: Saying that bigotry seems to be a natural urge is not to excuse it. Some things are natural (eg. rape) but have nonetheless been deemed by modern society to be worth resisting.

Caveat #2: Evo-psych and just-so stories have long been problematic. Although this page dabbles in these, it merely lists untested hypothoses; it should not be interpreted as providing answers.

This page is written from the perspective that prejudice/bigotry are harmful to society, that countries would be stronger if they no longer discounted huge percentages of their productive workers. If you think that prejudice is actually beneficial from an evolutionary standpoint, then you probably won't be interested in this page.

(That isn't to say that the urge to be prejudicial didn't come from some evolutionarily-useful situation at one point in time... we're discussing etiology after all. However, in 90+% of situations, I believe this urge to be harmful to society)

a list of possible hypotheses

• intergroup conflict — Wow, that's the page I was looking for.
  (note: the word "group" has a specific meaning in sociology; group affiliation can form based on extremely trivial attributes)
• until 1850, we didn't understand what pandemics were caused by, so it made at least a little sense to try random things in case one of them worked (perhaps including suggesting that people with black skin are inherently "unclean") (however, now, we understand causality much better, so it no longer makes sense to do this)
• green-beard effect and medea

primatology

• rhesus monkeys take the IAT [2]