Heintzmann et. al., Bison phylogeography constrains dispersal and viability of the Ice Free Corridor in western Canada http://www.pnas.org/content/early/2016/06/01/1601077113.full.pdf Als Konsequenz wird eine (zweite), postglaziale Besiedlungswelle mit erneuter Öffnung des Korridors ab ca. 13.000 BP angenommen. "Consequences of the Postglacial Corridor Chronology for North American Human Prehistory. The expansion of bison into the corridor region provides proxy evidence for when this route was viable for human populations and, in doing so, allows further refinement of New World human settlement scenarios. Human genetic and archaeological evidence indicate that eastern Beringia and parts of the Americas well south of the ice sheets were populated by 14,000 cal y BP, suggesting that migration out of Beringia probably began more than 15,000 cal y BP ago (15, 34–36). Our chronology for the opening of the postglacial corridor indicates that a fully habitable corridor connected Beringia and interior North America by ∼13,000 cal y BP. This timing precludes the postglacial corridor as a southward route for initial human dispersal into the Americas, the corollary being that the first indigenous peoples leaving Beringia probably took a coastal route or potentially moved through western North America before glacial coalescence (37, 38). We find that a bison belonging to the northern clade (2a) reached the Edmonton area by 13,000 cal y BP. It is therefore possible that established northern human populations also reached the central corridor by this time. Evidence from the archaeological record supports this hypothesis. For example, Alaskan archaeological sites including Swan Point, Mead, Broken Mammoth, Tuluaq, and Dry Creek, which were occupied from ∼14,000 to 11,500 cal y BP, fea- ture a variety of projectile technologies, sometimes associated with microblade industries (39). Similar microblade technologies are present at Vermilion Lakes (Banff National Park) and Charlie Lake Cave by ∼11,500 cal y BP (28, 40, 41). In addition, human genetic data from Upward Sun River, Alaska, show founding New World mitochondrial haplotypes B2 and C1b in Alaska at ∼11,500 cal y BP. Small, isolated groups of people may therefore have continued to disperse from Beringia to interior North America well after the corridor region opened (14, 16, 41, 42)."