Palaeoproteomic investigation of archaeological sediments associated with ochre use in the Middle Stone Age of southern Africa

The African Middle Stone Age (MSA) represents the cultural and technological context associated with the emergence of Homo sapiens and the development of complex cognition. In this setting, ochre use is considered a multifaceted proxy for modern behaviour, allowing inferences about technical and symbolic aspects of Homo sapiens. Powdered ochre is reported in multiple southern African ethnographic and archaeological contexts alongside various organic materials, some of which are protein-based. Yet, the recovery of proteinaceous residues is rare in the MSA. Since proteins can offer insights into their tissue and species of origin, identifying proteins in association with ochre may help to infer its function. At Klipdrift Shelter (South Africa), the 60 000-year-old Howiesons Poort layers contain a laterally continuous, ochre-rich sediment surface, possibly over 1 m long, 40 cm wide, and up to 1 cm thick. We used palaeoproteomics to identify proteinaceous traces from this feature. Our analysis identified type I collagen confidently matching common eland (Taurotragus oryx) in two samples. Together with the feature's highly complex nature, these findings suggest the deliberate mixing of eland-derived proteins with ochre powder. Our results confirm that palaeoproteomics can be a reliable tool for reconstructing the protein component of the early human material culture.