The initial expansion of anatomically modern humans (AMH) occurred during a hyperarid event in
Africa that occurred 135-75 ka. Large-scale AMH spread in northern Eurasia started during the Middle Weichselian
glacial maximum, and proceeded during the subsequent mild interstadial (60-40 ka ago). This expansion which encompassed
the polar regions and southern Siberia proceeded at a remarkably rapid pace, suggesting the entire area being taken
up by uniform ‘periglacial’ landscape, equally suitable for AMH habitation. The ‘transitional’ industries (Chatelperronian,
Szeletian, Streletsian etc) have seen archaeological manifestations of early AMH expansion.