Humanizing trade: ancestral exchange.

• Author: Bailey, Ronald
• Position: Citings - Brief article

HUMAN BEINGS often trade with strangers. When chimpanzees, our closest evolutionary cousins, meet strangers, they routinely kill them. What accounts for humanity's greater penchant for cooperation?

Anthropologists traditionally have argued that our ancestors evolved while living in small bands of close kin, so cooperation within the band helped their genes survive. A study reported in the March II issue of Science casts doubt on this theory, known as "inclusive fitness." A research team led by the anthropologists Kim Hill of Arizona State University and Robert Walker of the University of Missouri analyzed data on band composition for 32 contemporary hunter-gatherer societies. "In our sample of 32 societies," they...