The Middle-Upper Paleolithic transition in Northwest Italy: new evidence from Riparo Bombrini (Balzi Rossi, Liguria, Italy)

We report here preliminary results from four seasons of excavation at the rockshelter of Riparo Bombrini (2002–2005). Three markedly separate horizons were uncovered: the deepest, comprising Levels M1-7, yielded abundant Mousterian lithics and faunal remains. A second macro-unit, corresponding to Levels MS1-2, is only a few decimeters thick and is characterized by the presence of large limestone blocks from partial collapse of the shelter's vault. The scarcity of material and presence of carnivore coprolites suggest sporadic human occupation. The third macro-unit, constituted by Levels A1-3 and following immediately above Levels MS1-2, contains a rich Proto-Aurignacian industry, including Dufour bladelets, bone tools, abundant ochre, numerous decorative objects (mainly perforated shells) and widespread use of exotic raw material. New AMS dates and stratigraphic and sedimentological evidence indicate that the appearance of the Proto-Aurignacian at Bombrini dates to around 41 ky cal BP, in a phase of climatic degradation, paralleling the conditions observed for the transition at other northern Italian sites. While preliminary faunal analysis suggests little change in site use over time, the composition of the lithic assemblages point to a marked technological discontinuity between the two time periods. Riparo Bombrini's stratigraphic sequence affords important details about the environmental and cultural dynamics that marked the expansion of modern humans into Europe and the disappearance of Neandertals in that region during OIS 3. The association of a rich Proto-Aurignacian complex with an anatomically modern deciduous human tooth enhances further its importance for understanding early Upper Paleolithic in Italy.