A Comparison of Dietary Isotopes in Pulp Stones and Incremental Dentine from Early Neolithic Individuals of the Whitwell Long Cairn, England

Abstract

Objectives: This study investigates if palaeodietary information can be obtained from pulp stones through stable isotope analysis, presents a method for their extraction from tooth samples, and assesses their utility as a source of paleodietary information when coupled with the incremental dentine method. Materials and Methods: Six tooth samples (2 per individual), four of which contained pulp stones, were selected from three Early Neolithic (3720–3650 cal BC) individuals from the Whitwell Long Cairn in Derbyshire, England. After demineralization, each tooth was divided into 1 mm increments. Stable isotope analysis of collagen was conducted on each dentine increment and a portion of each pulp stone. Results: All samples met the quality control criteria for well-preserved collagen. Excluding the pulp stones, the mean δ13C value of the teeth sampled was −21.5 ± 0.2‰ and the mean δ15N value was 9.9 ± 0.5‰, suggesting these individuals had a terrestrial-based diet. The pulp stones produced similar δ13C values between −21.6 and −21.4‰ and δ15N values between 9.1 and 9.8‰. Discussion: The results demonstrate that paleodietary information can be obtained from pulp stones through stable isotope analysis. There are, however, significant challenges in interpreting this data, particularly as to inferring the timing and duration of their formation. The pulp stone results were compared with the incremental dentine profiles for each person to further investigate when they might have formed. For two individuals, the pulp stones appear to reflect diet from a time period after childhood and adolescence. For the third individual, it could not be determined if the pulp stones reflect a contemporary or later time period than the incremental dentine series. All teeth with pulp stones have moderate to severe wear on the occlusal surface, which could have been a contributing factor to their development.