The Coevolution of Altruism, Parochialism and War - Santa Fe Institute

Parochial altruism: the problem
• Parochialism --favoring ethnic, racial or other insiders over
outsiders – and altruism is commonly observed human
behaviors that are well documented in experiments (insider
favoritism is far from universal, however).
• Parochials forego beneficial interactions with ‘outsiders’
e.g. exchange, co-insurance, and access to information
• Parochial altruism is puzzling from an evolutionary
perspective because both reduce the actor’s payoffs
(whether fitness or material well-being) by comparison to
other group members who eschew these behaviors.
• The big idea: neither parochialism nor altruism is could
evolve separately, but the synergies between them allow
for their co-evolution.