The Evolution of Ethnocentric Behavior

Ethnocentrism is a nearly universal syndrome of attitudes and behaviors. Behaviors associated with ethnocentrism include cooperation with members of the in-group, but not out-groups. We show that ethnocentric behavior can emerge from a simple evolutionary model of local competition between individuals. Our agentbased model treats interactions as one-move Prisoner’s Dilemmas, and the inheritance of strategies as genetic, cultural, or (most plausibly) both. Results from the model demonstrate that ethnocentric behavior can evolve even when direct reciprocity is impossible, opportunities for “cheating ” exist, and agents have minimal cognitive ability. When cooperating is relatively costly, ethnocentric behavior can even be necessary to sustain cooperation. Ethnocentrism Ethnocentrism is a nearly universal syndrome of attitudes and behaviors. The attitudes include seeing one’s own group (the in-group) as virtuous and superior and an out-group as contemptible and inferior. The attitudes also include seeing ones own standards of value as universal. The behaviors associated with ethnocentrism are