Revised age of late Neanderthal occupation and the end of the Middle Paleolithic in the northern Caucasus

Abstract

culture and biology is more complex than traditionally assumed. Revised, improved, and corrected regional LMP and EUP chronologies are required to assess any possible associations between Neanderthal extinctions, AMH dispersals, and climatic events (6). Before bone pretreatment by ultrafiltration (7) and charcoal pretreatment by acid–base oxidation/stepped combustion (8), radiocarbon (14C) ages appear to have systematically underestimated the true age of LMP and EUP deposits, artifacts, and fossils by up to several thousand years (5, 9). This resulted in a “coexistence effect” (10) that gave the impression of a significant temporal overlap between late Neanderthals and AMHs in certain regions that is not supported by lithostratigraphic data. Direct 14C dating of Neanderthals and AMH fossils (5, 11–17) is of vital importance to the study of the Middle to Upper Paleolithic (MP-UP) transition/replacement events in Eurasia. Such dating projects can clarify and often reject presumed associations between specific hominin fossils and LMP and EUP archaeological contexts, provide reliable chronological frameworks for the calibration of molecular clocks and phylogenetic simulations, and allow the derivation of more accurate estimates of the timing and duration of Neanderthal extinction and AMH establishment in Eurasia. There are, at present, direct 14C dates of Neanderthal fossils from seven Eurasian sites (from east to west): Okladnikov (Russia), Mezmaiskaya (Russia), Vindija (Croatia), Kleine Feldhofer (Germany), Spy (Belgium), Les Rochers-de-Villeneuve (France), and El Sidrón (Spain). Of these, two dates from Okladnikov, four dates from Mezmaiskaya, seven dates from Vindija, and six dates from Spy are younger than 36 ka 14C BP and hence suggest the possibility of late Neanderthal survival (5). However, only the extraction protocols of two of the Vindija dates (OxA-X-2089-06 and OxA-X-2094-10) (12), two of the Okladnikov dates, and three of the Spy dates (13), involved the ultrafiltration or similarly rigorous pretreatment step (see below). The redating of fossils using improved chronometric methods has drastically altered current interpretations regarding late Neanderthal survival/extinction and their possible interactions with AMHs. This paper reports chronometric data from Mezmaiskaya Cave of well-provenanced LMP faunal and human fossil material in an attempt to provide highresolution temporal data on the termination of Middle Paleolithic occupation and Neanderthal extinction and the establishment of AMH populations in the Caucasus. Mezmaiskaya Cave is located 1,310 m above sea level in the Azish-Tau karst ridge in the northwestern Caucasus (18, 19). Since 1987, about 80 m2 have been carefully excavated to a maximum depth of 5 m, yielding thousands of lithic and organic artifacts and a rich faunal assemblage. Currently, the stratigraphic