Ecological variation and institutionalized inequality in hunter-gatherer societies

Area of Science:

• Evolutionary anthropology
• Archaeology
• Social inequality

Background:

• Research on institutionalized hierarchy often overlooks small-scale societies, focusing instead on chiefdoms and states.
• Understanding the origins of social and political inequality in simpler societies is crucial for a complete evolutionary picture.

Observation:

• This study analyzed environmental and social data from 89 hunter-gatherer societies along the Pacific coast of North America.
• Statistical models were employed to identify correlates of sustained political and economic inequality, accounting for spatial and historical dependencies.

Findings:

• The spatiotemporal distribution of resources, particularly reliance on and ownership of clumped aquatic resources (e.g., salmon), strongly predicts political-economic inequality.
• Inequality was measured by social ranking, unequal food access, and the presence of slavery.
• Population pressure, scalar stress, and intergroup conflict showed minimal correlation with inequality.

Implications:

• Findings support evolutionary ecological models where control over concentrated, defensible resources drives hierarchy formation.
• This mechanism, involving extraction of labor and allegiance, may explain hierarchy emergence in diverse small-scale societies.
• The study highlights resource control as a more significant factor than population or conflict in early inequality.