Complete Idiot’s Guide to American History
by Alan Axelrod
A Stroll Across the Bering Sea
Several times during what paleontologists call the Quaternary Period—that’s their name for the last two million years—a “land bridge” emerged in the Bering and Chukchi Seas as the sea level dropped due to the expansion of the ice cap surrounding the North Pole. The theory is that anywhere from 10,000 to 45,000 years ago, human beings used the Bering land bridge to enter the New World, migrating from what is now northeast Asia to northwestern North America. Beringia, as the land bridge is sometimes called, disappeared when the major continental ice sheets and other glaciers melted, causing the sea level to rise again.