Division of Labor, Economic Specializationand the Evolution of Social Stratification

This paper presents a simple mathematical model that shows how economic inequalitybetween social groups can arise and be maintained even when the only adaptive learningprocesses driving cultural evolution increases individual’s economic gains. The keyassumption is that human populations are structured into groups, and that cultural learning ismore likely to occur within groups than between groups. Then, if groups are sufficientlyisolated and there are potential gains from specialization and exchange, stable stratificationcan sometimes result. This model predicts that stratification is favored, ceteris paribus, by (1)greater surplus production, (2) more equitable divisions of the surplus among specialists, (3)greater cultural isolation among subpopulations within a society, and (4) more weight givento economic success by cultural learners. We also analyze how competition among societies,both egalitarian societies and those with differing degrees of stratification, influences thelong-run evolution of the institutional forms that support social stratification. In ourdiscussion, we illustrate the model using two ethnographic cases, explore the relationshipsbetween our model and other existing approaches to social stratification within anthropology,and compare our model to the emergence of heritable divisions of labor in other species...