Social differentiation in the pre-Hispanic horticultural societies of central Chile (200–1500 AD). A stable isotope study

Abstract

The horticultural societies of the central zone of Chile in the first millennium AD and the first half of the second have been the subject of archaeological study for many years, and their cultural contexts have been described extensively. Their material culture, lifeways and settlement patterns present significant differences between the Bato and Llolleo groups in the Early Ceramic period (200-1200 AD) and between these and the Aconcagua groups of the Late Intermediate period (1000-1500 AD) (Falabella et al., 2016). Increasing complexity, social differentiation and changes in polity structure have been proposed, but robust data are still missing for many of these interpretations. The object of this work was to contribute to the identification of inter- and intra-group social differences in mobility, sex and age patterns and maize consumption, based on stable isotope analysis of human bones and a sub-sample of teeth. Analysis of the C, N and O stable isotopes in collagen and bioapatite extracted from the samples showed differences between the three groups studied in spatial mobility patterns and consumption of C-4 plants, suggesting that local communities organized themselves according to distinct social strategies at the regional level, and developed different horticultural practices and uses of maize. Among the Aconcagua groups a larger contribution of C-4 plants was found in children and in adult males, making visible sex and age categories. The results support archaeological data and contribute to a better understanding of gender issues and social organization in the groups studied.