We can define two main contrary approaches to the origin of the Initial Upper Palaeolithic (IUP) blade industry in Transbaikal (South Siberia), which represented by tolbaga culture. These are the local formation on the base of Middle Palaeolithic (MP) (Lbova, 2005; Konstantinov, 1994) and in the result of the migrations from the adjacent territories (Rybin, 2009). Resolving this question, we should understand the degree of the tolbaga culture technological distinctiveness comparing with IUP industries in neighboring regions and its relation with the local cultures of the previous period.

Tolbaga culture is characterized by the predominant production of large blades and tools on them with using bidirectional knapping from subprismatic and flat cores in the primary knapping; toolkit conjoins Upper and Middle Palaeolithic tool types. Foliate bifaces are absent. Among specifical modes of tools' shaping, we should note the use of ventral/bifacial trimming at tools basal part and forming small tangs. All sites of the tolbaga culture present bone tools, non-utilitarian items, and complicated organization of the inhabited area displayed dwellings' remains, hearths, areas of tool production, middens and others defined in the cultural horizons. The tolbaga culture sites are dated back to the period of 47 – 27-26 kya (calibrated) (Konstantinov, 1994; Lbova, 2000; Tashak, 2011; 2014; Buvit et al. 2016).

MP at the Transbaikal territory is not enough investigated. Not numerous materials from the dated horizons (Khotyk, levels 5 and 6) do not allow characterizing specific traits of the Transbaikal MP in detail. Numerous materials of MP-appearance from the surface scatters do not give us a precise chronological position. The relationship with the local MP-assemblages is not obvious. However, some authors (Lbova, 2005; Konstantinov, 1994) propose the IUP origin on the base of MP.

Materials of the IUP sites from Transbaikal are considerably similar to those from Altai and Mongolia. At the same time, Transbaikal IUP materials stand out among the industries of adjacent territories for the seldom using knapping from the narrow end for getting blanks and also for the absence of bifaces, which are considered as one of the characteristic features for IUP industries of Altai and Mongolia.

We can observe similarities between the tolbaga culture and far-distant IUP industries of Lebanon. We identify in tolbaga culture materials not only general technological traits marking all IUP industries (Kuhn, Zwyns, 2009) but also some specific characteristics for the Boker-Tachtit industry (Rose, Marks 2014). These traits are: bipolar knapping with using crests, which, to Meignen (2012) opinion, is not common for the Lebanon IUP; Transbaikal points with bifacial trimming resemble Emireh points; the mode of the tang shaping at some tolbaga culture tools is similar to the “additional” characteristic of the Emiran (Rose, Marks 2014) – right lateral/bilateral nibbling at the base of Levallois points.

Hence, we suppose considerable influence of the migrations at the tolbaga industry origin in Western Transbaikalia. Penetrations of migrants at this territory were earlier 45 kya, likely at the end of Middle Palaeolithic from the Near East.