A multifaceted approach towards interpreting early life experience and infant feeding practices in the ancient Atacama Desert, Northern Chile

Interpreting early life experience in the past is of considerable interest to archaeologists, yet remains fraught with difficulty. Children are sensitive barometers of population health in general. In addition, infant feeding practices, and stresses experienced during infancy and childhood, have important effects on adult health and demographic changes. Understanding how diet and physiological stress interact is therefore of significance, but most bony indicators of stress have non-specific etiologies that cannot be tied to events during childhood. The recent advent of incremental isotopic techniques means we now have the potential to identify periods of stress and dietary change during childhood through changes to stable carbon and nitrogen isotopic ratios during tissue formation. Being able to establish these individual weaning trajectories allows us to consider individuality in past weaning choices, giving the bioarchaeologist a more nuanced picture of the past. Here, we investigate whether combining paleopathological and isotopic data can give insight into the synergy between infant feeding and stress. We present a case study of a 5-year-old child from an early agricultural period archaeological site in the northern Atacama Desert, Chile. We show that, despite physiological stress likely affecting isotopic ratios in this individual, a weaning curve is visible and the interpretation of weaning behaviour is possible. In addition, we suggest that there is isotopic evidence for a micronutrient deficient weaning diet that may be correlated with bony evidence for pathology.