The timing of infant weaning in the past is important for its implications for birth-spacing and infant survival, and hence for population maintenance or growth under different socio-economic regimes. Prior to the adoption of agriculture, breastfeeding is believed to have been more prolonged amongst hunter-gatherers due, at least partly, to the lack of suitable weaning foods that are available to agriculturalists. The introduction of pottery possibly also changed weaning patterns due to shifts in food preparation even prior to the adoption of domesticated foods. Here we apply stable carbon and nitrogen isotope sequential samples on dentine to explore differences in diet relating to weaning age, social roles and food sharing between children and adults in a well-preserved Mesolithic/Neolithic population from the cemetery of Zvejnieki, Latvia. We address whether there are differences in diet between the Mesolithic and the Neolithic periods, defined here by the appearance of pottery rather than the adoption of agriculture. Considerable variability in weaning patterns was observed, but in general individuals tended to be breastfed from birth, with the contribution of breast milk declining after the age of 6–12 months, and completely withdrawn by the age of 3 years. We note a difference in δ15N dentine profiles between the Mesolithic and Neolithic, which may be linked to the introduction of pottery. We also assess differences in diets in relation to identities marked in death, specifically the presence or absence of animal tooth pendants. The carbon and nitrogen isotope profiles for sequentially sampled first molars show that adults who were buried without animal tooth pendants as grave goods consumed more freshwater resources during their childhoods than those buried with animal tooth pendants. We conclude that infant and childhood diet reflected different societal roles or identities within the population that continued into adulthood.
