Exposure to high heat increases aggression. This study investigates a direct causal link between heat shocks and outgroup discrimination in Germany.

Field Experiments, Germany

Two large-scale field experiments revealed that exposure to heat shocks directly affects discriminatory behavior. German citizens showed reduced willingness to help Muslim immigrants during heat exposure compared with usual conditions.

Help Rates Unaffected by Temperature toward Ingroup

Interestingly, helping rates towards fellow Germans remained unchanged regardless of temperature changes. This contrast highlights the specific impact on outgroups under thermal stress.

Physiological Basis for Discrimination

The findings suggest that discriminatory behavior toward outgroups may have a physiological basis rooted in basic human responses to environmental stressors.