Historically heterogeneous populations have lower levels of outgroup prejudice; some evidence that diversity in the current population was related to increased prejudice

Population Diversity and Ancestral Diversity As Distinct Contributors to Outgroup Prejudice. Ilan Shrira. Personality and Social Psychology Bulletin, October 21, 2019. https://doi.org/10.1177/0146167219880190

Abstract: Previous research has shown conflicting findings on how population diversity influences outgroup prejudice. In some cases, prejudice is greater when minority groups make up a larger portion of the population, whereas in other cases, prejudice is lower as diversity increases. This article examined how the diversity of a culture’s ancestry—or its historical heterogeneity—would be related to outgroup attitudes. Historically heterogeneous populations descend from ancestors who have migrated from many parts of the world over the past 500 years and, as a result, have a longer legacy of contact with diverse groups of people. The results of two cross-cultural studies found that greater heterogeneity predicted lower levels of outgroup prejudice, and some evidence that diversity in the current population was related to increased prejudice. The findings suggest that intergroup attitudes have deeply entrenched roots that cannot be fully understood by looking at current indicators.

Keywords prejudice, culture, attitudes, ancestry, values