Environment alone cannot explain cultural differences between groups

Evidence

The cultural differences between the Nuer and the Dinka cannot be accounted for by subtle ecological differences between their territories. After 1820, the Nuer began successfully conquering and settling on Dinka lands. After more than 100 years of occupying the “Dinka environment,” no Nuer had become Dinka; however, many conquered Dinka had adopted Nuer practices. We cannot see how this, and similar examples, can be reconciled with the idea that environmental differences cause cultural variation. — Joe Henrich and Robert Boyd, The Evolution of Conformist…, 112

Hypothesis 1: Environmental variation. Authors from otherwise disparate points of view (behavioral ecology, Hill and Hurtado 1996: 14; and cultural materialism, Harris 1979: 55–56) have argued that differences in physical, ecological, or economic environments are the main cause of variation among groups. These researchers suggest that members of human groups are similar because they live in the same environment, and people living in different human groups are different because they inhabit different environments. Of course, in the short run, people may differ because of differences in the social environment, but, according to this view, in the longer run the social environment is shaped by ecological circumstances. We do not believe that this hypothesis can explain the widespread existence of culturally distinct groups whose behavior differs in many important ways despite the fact that they inhabit very similar physical and ecological environments. — Joe Henrich and Robert Boyd, The Evolution of Conformist…, 102

Before 1820, the Nuer and Dinka (Kelly 1985) occupied adjacent regions in the southern Sudan. Despite inhabiting similar environments and possessing identical technology, the two groups differed in significant ways. … The cultural differences between the Nuer and the Dinka cannot be accounted for by subtle ecological differences between their territories. After 1820, the Nuer began successfully conquering and settling on Dinka lands. After more than 100 years of occupying the “Dinka environment,” no Nuer had become Dinka; however, many conquered Dinka had adopted Nuer practices. We cannot see how this, and similar examples, can be reconciled with the idea that environmental differences cause cultural variation. — Joe Henrich and Robert Boyd, The Evolution of Conformist…, 111

Categorization

• XREF: The directional asymmetry of cultural adoption (conquered Dinka become Nuer, not vice versa) mirrors majority-status adoption dynamics discussed in Achebe’s and other colonial-contact material. — connects to: Nonconformity is costly because deviant behaviors fail to complement the culture.; Ecology cannot explain divergent cultural traits among neighboring Amazonian groups — Joe Henrich and Robert Boyd, The Evolution of Conformist…, 110
• ADDENDUM: Connects to the Dinka/Nuer cattle-herding example as a classic demonstration that ecology alone doesn’t determine culture, complementing the cross-cultural material on sacrifice and dress that also treat culture as autonomous of environment.
• corroborated: 3 independent passages support this claim — Joe Henrich and Robert Boyd, The Evolution of Conformist…, 112; Joe Henrich and Robert Boyd, The Evolution of Conformist…, 102; Joe Henrich and Robert Boyd, The Evolution of Conformist…, 111