Assessing weaning stress – Relations between enamel hypoplasia, δ18O and δ13C values in human teeth obtained from early modern cemeteries in Wroclaw, Poland

Abstract

ObjectivesThe aim of this paper is to assess linear enamel hypoplasia (LEH) on canines of adults from early modern Wroclaw cemeteries to compare δ13C and δ18O values in enamel formed before, during and after LEH formation, and to attempt to find a link between the selected indicators of the weaning process. Material and methods15 permanent canines with visible LEH were selected for analysis. Age at LEH formation was estimated using the Reid and Dean method. The perikymata count was used to estimate the duration of LEH formation. Incremental stable oxygen and carbon isotopes analysis was performed on tooth enamel to infer stress related to weaning and dietary patterns. Kruskal–Wallis ANOVA, Mann–Whitney U test and Spearman correlation were used in statistical inference. ResultsThe average age of LEH formation was 3.14 years, with an average duration of 111 days. Stable carbon isotope values consistently increase in 73% of the individuals sampled. The values of δ18O do not show a dominant pattern. The average value of δ13C increases over the time of enamel formation. The δ13C values collected below LEH were negatively correlated with δ18O values and the duration of LEH termination. ConclusionsMarking of carbon and oxygen isotopes indicates different stages of weaning. Advancements in diet change (determined by higher δ13C) corresponds with faster recovery after physiological stress episode. There is no evidence for different breastfeeding models between distinct parishes in early modern Wroclaw.