The 84th Annual Meeting of the American Association of Physical Anthropologists (2015)

Investigating Economic Specialization on the Central Peruvian Coast: A Reconstruction of Late Intermediate Period Ychsma Diet Using Stable Carbon and Nitrogen Isotopes


1School of Human Evolution and Social Change, Arizona State University, 2School of Earth and Space Exploration, Arizona State University

March 27, 2015 10:15, Grand Ballroom C Add to calendar

This project uses stable carbon and nitrogen isotopes in archaeological human bone collagen to test a classic ethnohistoric model that proposes Central Andean coastal polities were comprised of multiple economic specialist communities. Specifically, we focus on the Ychsma polity (c. AD 900-1470) of the Rimac and Lurín Valleys on the central Peruvian coast. This region subsequently became the location of key Inca ceremonial and administrative centers and later the capital city of the Spanish Vice Royalty. Understanding the nature and impact of the Inca conquest and Spanish colonization requires empirical investigations of Ychsma social organization and interactions prior to these sociopolitical transformations. Previous emphasis on ethnohistoric data to understand Ychsma social organization has led to a generalized representation of Ychsma communities as internally homogenous and territorially bounded according to subsistence specialization. We used stable carbon (δ13C) and nitrogen (δ15N) isotope analysis of archaeological human bone collagen to reconstruct the diets of 40% of individuals recovered from burials at Armatambo (n=67/168), associated ethnohistorically with a fishing specialist community and at Rinconada Alta (n=46/111), associated ethnohistorically with an agricultural specialist community. Individuals buried at Armatambo exhibit significantly increased mean stable nitrogen isotope ratios, suggesting these individuals consumed relatively greater quantities of marine resources. Variation within large-scale trends, however, suggests sub-group specialization and/or fluidity between groups.

Funding provided by the National Science Foundation (BCS-1143568), the Wenner-Gren Foundation (8468), the Sigma Xi Scientific Research Society, and Arizona State University.