The Eskimos likely could have walked over to North America 20,000 years ago when the sea level was 400 feet lower than now

If you can imagine that 20,000 years ago that sea level was 400 feet below now it is quite easy to imagine people just walking across where the Aleutian Islands are now which were like Mountain Peaks then when Sea levels were 400 feet below now.

Like I said before Glaciers and snow and cold weather don't stop all people from moving around in Arctic Conditions or on glaciers only some of them. Mostly I think what it would do is prevent a lot of births of humans because it is much harder to survive and get enough food when it is that cold. This is my thought during Ice Ages or when it gets really cold for a longer period of time maybe even throughout the summers in the polar regions down to maybe Northern California.

For example, the carved Granite of Yosemite National Park and El Capitan and Half Dome and Star King and others were all carved by Glaciers. So, we know these glaciers in the past came as far south as far as Yosemite National Park. This is pretty far south.

We could also imagine then that these glaciers also came as far south as Yosemite at least on the Rocky Mountains this far south as well as it did in the Sierras and Cascade Ranges in California, Oregon,Washington and Colorado and all the rest of the Rocky Mountain States all the way up into Canada.