The implications of the Middle-Upper Paleolithic chronological boundary in the Caucasus to Eurasian prehistory

The systematic excavations at Ortvale Klde rockshelter and Dzudzuana Cave in Western Georgia uncovered an occupational sequence spanning the Late Mousterian and Early Upper Paleolithic. The cultural break between the two entities is dated to ca 36-34 Ka BP and reflects a relatively late survival of Neanderthals in this region; similar results were reported from Mezmaiskaya cave on the northern slopes of the Caucasus. The major difference between the Late Mousterian industries on the two sides of these mountains, namely Eastern Micoquian with foliates in the north and a Mousterian rich in scrapers in the south indicates that the topographic heights were a cultural boundary during the Middle Paleolithic. The similarity in the Early Upper Paleolithic assemblages across the Caucasus, rich in retouched and backed bladelets and bone and antler objects, demonstrates a rapid expansion of modern humans. No positive evidence was found for the presence of the classical Aurignacian culture that according to current models emerged in western Europe.