Isotope analyses reveal differences in juvenile dietary patterns, subsistence practices, and landscape-use between people buried in caves and in megalithic graves
Alto de la Huesera megalithic graves in Rioja Alavesa region, northern Spain.(Photo credit: Dr Javier Ordoño)
In a new study published today, a multi-isotope study of teeth from skeletons buried in megalithic graves and caves in a small region in northern Iberia has revealed the presence of culturally distinct communities with different lifestyles coexisting during the Late Neolithic (3500-2900 years BC). The authors (including Professor Julia Lee-Thorp and Professor Rick Schulting and Dr Teresa Fernandez-Crespo) suggest that the findings “demonstrate a degree of socio-cultural complexity not previously appreciated”, providing insights into more than a century of debate about why Neolithic people used different burial locations in western Europe. It had been thought that such distinctions in burial practices might reflect different socio-economic or cultural backgrounds, but it was impossible to demonstrate this, or the extent of such differentiation and the degree of interaction between those buried in caves and megalithic graves.
Teeth are biological ‘hard-drives’; they hold essential information about the growth and development of the individual during their formation. Taking advantage of isotope composition as proxies for diet and mobility, and the incremental formation of tooth structures, Fernández-Crespo and colleagues analyzed the molars of 32 Late Neolithic individuals from 6 sites in northern Iberia in order to reconstruct the early life-history of each individual during infancy and childhood. They established detailed sequences of dietary data through micro-sequential isotope analyses of dentine to track sub-annual variation. They then compared this information against indications in the enamel for plant consumption from strontium/calcium concentration ratios, and dietary and mobility information from carbon, oxygen and strontium isotope data.
The results showed significant differences in all isotope systems between people buried in caves and megalithic graves from early childhood onwards. Since these distinctions also overlap with distinctions in funerary practices, the authors suggest the existence of a profound cultural division. Fernández-Crespo et al. say that their results are indicative of “persistent socio-economic asymmetries between both groups” and that this early example could help us to address fundamental questions about the roots of inequality and difference that have plagued human societies for millennia.
Fernández-Crespo T, Snoeck C, Ordoño J, de Winter NJ, Czermak A, Mattielli N, Lee-Thorp JA, Schulting RJ, Multi-isotope evidence for the emergence of cultural alterity in Late Neolithic Europe, Sci. Adv. 2020; 6 : aay2169 22 January 2020