Stable isotope evidence of human diet in Mediterranean context during the Last Glacial Maximum

The Final Gravettian in Europe overlapped with the cold and dry climatic event of Heinrich 2 (ca. 27-23.5 kyr cal BP), which caused the contraction of human distribution over refuge regions in the southern peninsulas of Europe. Here, we consider the human subsistence in the northeast Iberian Peninsula, where an extensive range of small to large prey was available. Four human remains from the Serinyà caves were investigated using the stable isotope ratios of carbon, nitrogen, and sulfur of bulk collagen (δ¹³C_coll, δ¹⁵N_coll, δ³⁴S_coll) and of phenylalanine and glutamine amino acids (δ¹⁵N_Phe, δ¹⁵N_Glu). Direct AMS dating of the human and animal remains from the Final Gravettian levels of Mollet III, Reclau Viver, and Arbreda at Serinyà confirmed their chronological position from 27.5 to 22.6 kyr cal BP and the occurrence of four different human individuals. The δ¹³C_coll and δ¹⁵N_coll values showed a large contribution of terrestrial prey to the dietary protein of the individuals. The δ³⁴S_coll values were consistent with a subsistence based on the local continental resources, without detectable contribution of marine resource. The δ¹⁵N_Phe and δ¹⁵N_Glu values confirm that freshwater resources were not a substantial component of the diet of the considered individuals. Contrast in the isotopic amounts in bulk collagen could be interpreted as the result of different proportions of terrestrial prey in human diet at Serinyà. Altogether, the isotopic investigation reveals the importance of terrestrial over aquatic resources in the subsistence of the studied Final Gravettian individuals from the Serinyà caves in northeastern Iberia during the Last Glacial Maximum. It would be consistent with a scenario of a productive enough terrestrial ecosystem to sustain hunter-gatherer subsistence in this refuge region.