[HamiltonJay]

The land was VASTLY different now than it was then.... take a look at the size of the bridge via the drawings, it wasn't some small pidly thin piece of land, it had plains and coastline and was a very large area.. sea levels were something like 400 feet lower then, which opened a LOT of land

[RightWhale]

The land was VASTLY different now than it was then....

Not here. During the Ice Age, this land was ice-free just as now. Permafrost, muskeg, sabertooth, mammoth, muskox all still here, although the sabretooth and mammoth are subsurface now. It's the same, and you don't go far on foot in the summer. In the winter the Yukon River is a 12-lane superhighway. 12 thousand years ago the land route south was blocked. Still is, except for that gov't road.