Null results for the steal-framing effect on out-group aggression

Area of Science:

• Evolutionary Psychology
• Social Psychology
• Behavioral Economics

Background:

• The debate on whether intergroup conflict drives human prosociality is ongoing.
• The parochial altruism model posits that in-group cooperation coevolved with out-group aggression.
• Previous studies using the intergroup prisoner's dilemma game failed to demonstrate out-group aggression.

Purpose of the Study:

• To test if framing aggression to benefit the in-group promotes out-group hostility.
• To investigate the validity of the coevolutionary model of parochial altruism.

Main Methods:

• Two laboratory experiments were conducted with 176 Japanese university students.
• Participants played an intergroup prisoner's dilemma-maximizing difference game.
• A specific framing emphasizing in-group gain from out-group harm was implemented.

Main Results:

• The framing designed to promote out-group aggression was ineffective.
• Participants did not exhibit increased aggression towards out-group members.
• Individuals prioritized cooperation with in-group members over strategies involving out-group harm.

Conclusions:

• The findings do not support the coevolutionary model of parochial altruism.
• Human prosociality may not necessitate intergroup conflict for its evolution.
• The operationalization and framing of out-group aggression in experimental settings require further consideration.