Hunter-gatherer Mobility Analysed Through δ18O in the Patchy Environment of the Paraná Valley, South American Lowlands

Abstract

In this study we analyse the mobility of complex hunter-gatherers in the Lower Paraná wetland (South America) through δ18O values. To do this, we characterise the isotopic composition of water and bioapatite of stenoic and sedentary species from the region and the surrounding Pampa plain, and then we compare them with those obtained in human bones recovered at local archaeological sites. The results show that humans appear to have developed spatial stability strategies within certain areas, which is consistent with archaeological models of social circumscription among these pre-Columbian populations. Other finding of this study shows that any organism that moves along the middle and lower Paraná valley will not present differences in its δ18O values, but small transverse movements will produce significant variations, which relativises to some degree, the concept of ‘local’ and ‘non-local’ in the region. This study also addresses the methodological problems related to the characterisation of δ18O values in irregular environments, highlighting the importance of developing baselines based on local biocenoses.