For the majority of human history, people lived in hunter-gatherer bands where they never met anyone of another race. The nearest such person was likely to be hundreds or thousands of miles away. It's only extremely recently, in evolutionary terms, that humans have become mobile enough to encounter other races. Why, then, should our brains have evolved to have such automatic, inevitable, aversive processing of people of other races when such encounters have played virtually no role in how humans evolved? The answer is, they haven't. The aversive processing is neither automatic nor inevitable.

Are humans hard-wired for racial prejudice?