Variability in the Sibiryachikha assemblages of the Altai Mountains (based on materials from Okladnikov cave layer 2)

This article, based on new data from comprehensive studies of assemblage from Okladnikov Cave layer 2, explores the variability of Middle Paleolithic Sibiryachikha variant of the Altai Mountains. Using methods such as scar pattern analysis, experimental use-wear analysis, attributive analysis, etc., we specify the characteristics of the assemblage by extending the nomenclature of technical flakes relating to radial flaking, evaluating the share of the bifacial component including bifaces, their fragments, and bifacial technical flakes, revising the typology of the tools. The Sibiryachikha assemblage of Chagyrskaya Cave layer 6c/1 is correlated with that of Okladnikov Cave layers 1 and 2, revealing not only common features but also differences in primary and secondary reduction. At Okladnikov Cave, unlike Chagyrskaya, the reduction cycle is incomplete, the tools are smaller, and the share of convergent scrapers and chips resulting from the processing of bifaces is higher. We conclude that the distinctive feature of Okladnikov industry is a considerably more intense modification of raw materials owing to their less availability. Because Okladnikov Cave is situated in the immediate vicinity of the sources of raw material, implying its abundance, we suggest that pebbles of suitable quality and size were less available. As a result, rejuvenation of lithic tools was more intense, and bifacial thinning flakes were used as tool blanks. The Okladnikov Cave industry reveals the complex behavioral models, previously unknown, among eastern Neanderthals, which do not rule out the import of bifacial tools or blanks made of high-quality raw material.