Residential Mobility and Resource Use in the Chiribaya Polity of Southern Peru: Strontium Isotope Analysis of Archaeological Tooth Enamel and Bone K. J. KNUDSON* AND J. E. BUIKSTRA Center for Bioarchaeological Research, School of Human Evolution and Social Change, PO Box 872402, Arizona State University, Tempe AZ 85287, USA ABSTRACT The Chiribaya were a complex polity during the Andean Late Intermediate Period (c. AD 1000–1300) in the Ilo and Moquegua Valleys of southern Peru. Recent research has demon- strated that the Chiribaya polity was a sen˜orı´o, a confederacy of economically specialised parcialidades. Here we test hypotheses regarding the movement of individuals and resources among the Chiribaya-affiliated sites of Chiribaya Alta, Chiribaya Baja, San Gero ´nimo and El Yaral, as well as from outside of the Ilo and Moquegua Valleys. Although archaeological human enamel and bone strontium isotope ratios from Chiribaya Baja and San Gero ´ nimo cluster closely, there is a wider variety of strontium isotope ratios observed at Chiribaya Alta and El Yaral. This indicates that individuals buried in cemeteries at these sites had access to a wider variety of resources, and probably moved between different geological zones through- out their lifetimes. Copyright ß 2007 John Wiley & Sons, Ltd. Key words: Andes; bone chemistry; migration; palaeodiet Introduction Although recent research on the Chiribaya polity (c. AD 1000–1300) of southern Peru has demonstrated the complex economic relation- ships among various Chiribaya-affiliated commu- nities, the movement of individuals and resources between them is not well understood. This research project complements earlier palaeodie- tary analyses of archaeological human bone from Chiribaya-affiliated sites by incorporating stron- tium isotope analyses of archaeological human tooth enamel and bone from a subset of the same individuals to elucidate residential mobility. In this paper we begin with a brief discussion of residential mobility studies using isotopic data, followed by a presentation of the Chiribaya- affiliated sites included in this project, our strontium isotope results, and our interpretations of these data. Residential mobility through strontium isotope analysis Archaeologists are increasingly turning to analyses of both heavy and light stable isotopes to identify archaeological residential mobility. Although strontium concentrations vary accord- ing to trophic level, strontium isotope ratios vary International Journal of Osteoarchaeology Int. J. Osteoarchaeol. 17: 563–580 (2007) Published online 15 May 2007 in Wiley InterScience (www.interscience.wiley.com) DOI: 10.1002/oa.916 * Correspondence to: Center for Bioarchaeological Research, School of Human Evolution and Social Change, PO Box 872402, Arizona State University, Tempe AZ 85287, USA. e-mail: kelly.knudson@asu.edu Copyright # 2007 John Wiley & Sons, Ltd. Received 24 May 2006 Revised 12 December 2006 Accepted 21 December 2006