The progress of the early human migration from Asia into the Americas was incredibly slow. In fact, a new column in the journal Science by University of Utah Anthropologist Dennis O'Rourke and two other researchers argues that the people whose descendants ended up populating the American continents may have spent as many as 10,000 years inhabiting the Bering Land bridge. KCPW's Roger McDonough spoke with professor O'Rourke to find out more.

Image: This map shows the outlines of modern Siberia (left) and Alaska (right) with dashed lines. The broader area in darker green (now covered by ocean) represents the Bering land bridge near the end of the last glacial maximum, a period that lasted from 28,000 to 18,000 years ago when sea levels were low and ice sheets extended south into what is now the northern part of the lower 48 states. University of Utah anthropologist Dennis O’Rourke argues in the Feb. 28 issue of the journal Science that the ancestors of Native Americans migrated from Asia onto the Bering land bridge or “Beringia” some 25,000 years ago and spent 10,000 years there until they began moving into the Americas 15,000 years ago as the ice sheets melted.

Photo Credit: William Manley, Institute of Arctic and Alpine Research, University of Colorado.