Temperature and outgroup discrimination

Abstract

High temperatures have been linked to aggression and different forms of conflict in humans. We consider whether exposure to heat waves increases discriminatory behavior toward outgroups. Using data from two large-scale field experiments in Germany, we find a direct causal effect of exposure to heat shocks on discrimination in helping behavior. As temperature rises, German natives faced with a choice to provide help to strangers in every-day interactions help Muslim immigrants less than they do other German natives, while help rates toward natives are unaffected by temperature. This finding suggests that there may be a physiological basis for discriminatory behavior toward outgroups.