Recent studies have suggested that the glaciers that helped form the bridge connecting Siberia and Alaska began receding around 17,000 to 13,000 years ago, leaving very little chance that people walked from one continent to the other...
My commnet:
I've heard this disputed though... In not too distant times before global warming of the past decades.. it was possible for people to travel across the ice in the Bering straight...and as late as this year a caption with a telling photo of a dog sled travelling over the ice reads:
"Hugh Neff of Skagway drives his team across the frozen Bering Sea at sunset, Mar. 15, 2006,..."
Source:
http://www.adn.com/iditarod/race_200...-7458545c.html
So even though the land bridge may have receded people still travel across the sea when it ices over...