Multi-proxy stable isotope analyses of dentine microsections reveal diachronic changes in life history adaptations, mobility, and tuberculosis-induced wasting in prehistoric Liguria (Finale Ligure, Italy, northwestern Mediterranean)

Objective: To reconstruct breastfeeding and weaning practices, metabolic stress including tuberculosis-induced wasting, and residential mobility of children in Neolithic and Metal Ages to infer their local ecologies. Materials: Seven permanent teeth from individuals dated to the Neolithic, Copper, Bronze, and Iron Ages buried in nearby caves in western Liguria, Italy. Methods: Carbon, nitrogen, and sulfur stable isotope analyses on dentine microsections. Tooth maturation was used to calculate age at death. Results: Two Neolithic children present longer pattern of weaning and appear to have been weaned using animal protein in contrast to the earlier weaning of Metal Ages children, which were probably weaned with vegetable resources. Sulfur isotopes suggest local origin of Neolithic and Cooper Age children, and non-local origins for Bronze and Iron Age children. Intense catabolism in the last two years is apparent in the adolescent with tuberculosis. Conclusions: Shortening in weaning patterns during the Metal Ages are likely driven by the intensification of agricultural practices and cultivation of new crops during Bronze and Iron Ages. Neolithic food choices and delayed weaning patterns may represent one of the strategies to maximize growth and immune potential in a local economy/ ecology with high-infectious load. Tuberculosis was a chronic and long-lasting disease. Significance: The first combined carbon, nitrogen, and sulfur analysis on prehistoric dentine microsections revealing changing human life history adaptations within the same region. Limitations: Small sample size. Suggestions for further research: Increase the sulfur isotope dataset, use new EA-IRMS equipment, and provide data on amino acid to better define weaning food composition.