A Stable Isotope Investigation of Palaeodiet and Residential Mobility During the Integration Period, Quito Basin, Ecuador

The Integration Period (500/600-1532 C.E.) saw pre-Columbian society in the Quito Basin of Ecuador develop more politically and socially complex chiefdoms focused around agricultural production and trade. In this study, carbon, nitrogen and oxygen isotopic analyses of bone and teeth from 115 individuals from the sites of Tajamar (n=73) and Nuevo Aeropuerto Internacional de Quito (NAIQ) (n=42) were performed in order to reconstruct short- and long-term dietary patterns, and residential mobility in the Quito Basin. Emphasis was placed on how/if these large-scale societal changes in the region affected group dietary patterns and individual choices and actions. The isotopic analysis of adult bone demonstrated that the long-term average diet varied substantially between the two sites. The diet at Tajamar consisted primarily of C4 plants (maize) with protein derived largely from plants and some lower trophic level domestic animal meat (likely guinea pigs [cuy]). At NAIQ, the diet was more generalized, having a mixed C3/C4 plant base with greater reliance on C3 plants and the consumption of both wild and domestic terrestrial animal protein. The differences between Tajamar and NAIQ are likely the result of the populations living within and exploiting different ecological zones within the environmentally diverse Quito Basin. Childhood dietary variations were assessed through the isotopic analysis of early-and late-forming teeth as well as juvenile bone. For most individuals, breastfeeding ceased before 2 years of age. By late childhood, the diet was similar to adult patterns for each respective site, with the possible exception of higher consumption of boiled/stewed beverages during later childhood. The high intra-site isotopic variability in early and late childhood tissues suggested the absence of a uniform nursing/weaning strategy. Individual actions also likely played a large role in adult dietary practices. The oxygen-isotope results for these Quito Basin human tissues and modern environmental waters showed high intra-site variability and are suggestive of geographic mobility. When combined with the carbon and nitrogen isotopic data, however, the results could also be indicative of greater autonomy in dietary choices and animal management practices by individuals at Tajamar and NAIQ