Intergroup cooperation unravels because free-riding and competition outcompete collective benefit.

Evidence

Modern evolutionary models of human cooperation support Darwin’s intuition: when the forces of intergroup competition are nonexistent or weak, self-interested behavior typically thrives. But as intergroup competition intensifies, strategies that suppress self-interest for the common good win out. Thus, the particular mixture of self-interested and self-sacrificial tendencies we find in a population partly depends on that population’s exposure to intergroup conflict. — Norenzayan, Ara, Big gods - how religion transformed…, 462 (#complicates, via linked claim)

Categorization

• XREF: connects to: Cooperative civic activities decline faster than individual ones — Robert D. Putnam, Bowling Alone The Collapse and Revival…, 127; Large dispersed interests fail to organize due to free riding — Martin Gilens and Benjamin I. Page, Testing Theories of American Politics:…, 34; Cross-racial cooperation can succeed despite divergent motives and interests — Evelyn Brooks Higginbotham, Righteous Discontent: The Women’s…, 425 (+10 more)

Broader Connections

• Intergroup competition shifts populations toward self-sacrificial cooperation #complicates (0.85) — Norenzayan, Ara, Big gods - how religion transformed…, 462
• Real cooperation runs on mixed motivations that can undermine one another #complicates (0.82)