No one home? New evidence for MIS 3 occupations in the Western Cape (South Africa) from Mertenhof Rock Shelter

Abstract Southern Africa features an intensively studied Stone Age sequence, though one with geographical and temporal gaps. The archaeology of Marine Isotope Stage (MIS) 3 remains understudied, particularly between ~ 50 − 25 ka. This period encompasses numerous ecological, demographic and behavioural changes, most notably the passage from Middle Stone Age (MSA) to Later Stone Age (LSA) technologies. In western South Africa, previous research postulated a hiatus in the cultural sequence during the second half of MIS 3, potentially reflecting depopulation due to hyperarid environments. Here we document rare occupations during this period in the Western Cape at Mertenhof Rock Shelter (MRS) by providing new chronometric and technological data. OSL estimates suggest two pulses of low-density occupations at ~ 50 ka and 41 − 37 ka, allowing for a diachronic assessment of technological changes. These sporadic MSA occupations complement the more widespread occurrence of open-air settlements along the Doring River during ~ 50 − 35 ka. At MRS, knappers procured local rock types and produced small flakes and some blades via platform and bipolar reduction but without Nubian methods. The retouched pieces feature splintered pieces and denticulates but mostly lack points. Notable differences to sites in eastern southern Africa underscore ongoing technological regionalization and demographic partitioning during MIS 3. The temporal changes in the sequence show no consistent trajectory towards the ELSA in the region that appears around 25 ka. Lithic and chronometric evidence from MRS supports scenarios of a long persistence of the MSA within MIS 3 in southern Africa and a late emergence of the LSA after 35 ka.