Brain scans have shown that when people see faces of other races, their amygdalas light up like home security systems. Some tout this as evidence of hardwired racial bias, evolved to keep the oddly colored “other” out of home territory. But as Robert Wright points out in this recent article, there would be few opportunities for interracial conflict in our geographically dispersed evolutionary past. The “other” would primarily be distinguished by different visual cues such as tribal emblems, because hostile neighboring tribes would generally be of the same race.
More recent brain scan experiments done on children show that, like menstrual cramps and unstoppable boners, neurological race rage doesn’t kick in until after puberty. While the question of “nature vs. nurture” is still open, this suggests that cultural forces are at work.
Wright’s line of reasoning is pretty solid when he says, “[T]hough we’re not naturally racist, we’re naturally ‘groupist.'”
Via The Atlantic:
There’s never been good reason to believe that human beings are naturally racist. After all, in the environment of human evolution–which didn’t feature, for example, jet travel to other continents–there would have been virtually no encounters between groups that had different skin colors or other conspicuous physical differences. So it’s not as if the human lineage could have plausibly developed, by evolutionary adaptation, an instinctive reaction to members of different races.
Nonetheless, people who want to argue that racism is natural have tried to buttress their position with evidence that racism is in some sense biological. For example: studies have found that when whites see black faces there is increased activity in the amygdala, a brain structure associated with emotion and, specifically, with the detection of threats.
Well, whatever power that kind of argument ever had–which wasn’t much, since the fact that a psychological reaction has a biological correlate doesn’t tell you whether the reaction is innate–it has even less power now. In a paper that will be published in the Journal of Cognitive Neuroscience, Eva Telzer of UCLA and three other researchers report that they’ve performed these amygdala studies–which had previously been done on adults–on children. And they found something interesting: the racial sensitivity of the amygdala doesn’t kick in until around age 14.
What’s more: once it kicks in, it doesn’t kick in equally for everybody. The more racially diverse your peer group, the less strong the amygdala effect. At really high levels of diversity, the effect disappeared entirely. The authors of the study write that ”these findings suggest that neural biases to race are not innate and that race is a social construction, learned over time.”
There’s a reason the previous sentence says “suggest” and not “prove.” As the authors note, it’s conceivable that “the increasing amygdala response to race [with age] may be driven by intrinsic factors of the child, such as puberty, rather than exposure to cultural messages.” For that matter, the correlation between peer group diversity and dampened amygdala response doesn’t mean the former causes the latter; it could work the other way around: maybe people with a mild response to racial difference wind up with more diverse peers.
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