Young children often observe society dividing its members–by ethnicity, religion, gender, or even favorite sports team. But a review by a Yale psychologist published August 14 in the journal Trends in Cognitive Sciences concludes that favoritism toward members of one’s own social groups may not be a learned behavior but an instinct triggered by belonging to that group. Although this favoritism can manifest as discrimination and stereotyping, it may have originally facilitated human evolution by boosting group living and social learning.
“Researchers have found that you can randomly assign someone to a group, and even if they theoretically have no vested interest in that group, they will have persistent favoritism for it, an ingroup bias, across a range of different measures,” says the review’s author Yarrow Dunham (@yarrowdunham, socialcogdev.com), an Assistant Professor of Psychology at Yale University. “Many theories attempt to explain inter-group dynamics by capturing the complexity of each group, but I argue that they can be explained with the simpler concept of mere membership, of us-and-them.”