Assessing the life history of an andean traveller through biogeochemistry: Stable and radiogenic isotope analyses of archaeological human remains from northern chile

Bioarchaeology and biogeochemistry can elucidate aspects of individual life histories that are often lost in the archaeological record. Here, we use stable and radiogenic isotope analyses of enamel, bone and hair to reconstruct paleodiet and paleomobility in an adult male interred along a pre-Columbian route connecting the northern Chilean coast to the inland Loa River Valley. Although this well-preserved burial included mortuary goods typical of coastal cultures, it was discovered in a vast, uninhabited part of northern Chile's hyper-arid Atacama Desert. Variation in carbon and nitrogen isotopes reflects dietary differences, while strontium and oxygen isotopes vary geologically and geographically. We use these data to examine paleodiet and paleomobility and to assess whether this was a coastal traveller seeking provisions from the interior or vice versa. Enamel stable isotope analysis is consistent with the consumption of a mixture of terrestrial and marine resources during the first years of life. Bone stable isotope analyses indicate habitual consumption of marine foodstuffs over the last 10-30 years of this individual's life. Interestingly, stable isotope analysis of hair samples provides more fine-grained information on this individual, suggesting movements between the coast and highlands in the months before his death. Radiogenic strontium isotope data are consistent with residence on the coast or in the Atacama Desert, but are lower than strontium isotope values from higher altitudes. These dietary and geological patterns are reconcilable with coastal residency; the isotopic data are consistent with foodstuffs and textiles found with the burial. Therefore, we argue that this individual was regularly moving from the coast to inland areas, crossing the hyper-arid Atacama Desert by following strategic interzonal routes that provided access to particular resources.