Anthropogenic fire fingerprints in Late Pleistocene and Holocene sediments of Sodmein Cave, Egypt

• First-time analyses of black carbon in 120,000 year old archaeological deposits. • Black carbon inputs highlight phases of increased human habitability and fuel availability. • Hot fires in the Pleistocene indicate human presence in Sodmein Cave. Sodmein Cave in Egypt is an exceptional archive for the study of past human behavior and anthropogenic fire history. Stratified remains of human occupation were excavated, ranging from the Middle Stone Age to the Neolithic. Hearths were repeatedly detected throughout the stratigraphy, with the lowest Pleistocene level having particularly large fire pits. This study is the first to apply a black carbon (BC) method on sediments bearing archaeology from the last 120,000 years. The method oxidizes BC to benzene polycarboxylic acids (BPCA) as a proxy for fire residue input. We detected significant changes in BC amounts throughout the stratigraphy; the highest contents in the form of two distinctive peaks were found in samples corresponding to the beginning of the Late Pleistocene (3.3 and 2.2 g BC kg −1 , respectively), indicating frequent burning. In the overlying layers, BC remained low (on average: 0.2 g BC kg −1 ) until the beginning of the Holocene, when contents increased, and human influence became visible again (1.7 g BC kg −1 ). Also, BPCA composition as a proxy for changes in fire temperature changed significantly over the stratigraphy. In the Pleistocene, residues of hotter fires were predominantly found, while the Holocene was characterised by a change to low-temperature fires. Variations in BC input and source are in agreement with the archaeological results, demonstrating the varying intensities and recurrence of human visits to the shelter during the last 120,000 years, but also show the potential to resolve different phases of human occupation more finely, when the archaeological findings are accompanied by geochemical BC analyses.