Intergroup competition boosts intragroup cohesion while shared tasks restore cooperation

Evidence

But before the study ended, Sherif and colleagues made two other important observations. First, they noted that intergroup competition increased morale, cohesiveness, and cooperation within each group, suggesting that intragroup cooperation and intergroup competition are two sides of the same coin (see replication by Blake & Mouton, 1962). Second, they found that creating a situation of interdependence by giving both groups a shared superordinate task (like fixing their broken down means of transportation) served to decrease competition and to increase cooperation across group boundaries. Just as competition creates conflict, cooperation breeds liking. — John T. Jost and Jim Sidanius, Political Psychology, 136

Categorization

• DEEPTHINKING: The two-sided coin insight — that ingroup solidarity and outgroup hostility are produced by the same mechanism — is a dense, keepable kernel with wide implication.
• XREF: connects to: Leaders build cohesion by recategorizing conflicts in shared terms. — Stephen Reicher, S. Alexander Haslam, and Nick Hopkins, Social identity and the dynamics of…, 90; Direct competition experiments reveal interspecies dominance obscured in the field — Robin Wall Kimmerer, Gathering Moss: A Natural and Cultural…, 294