The prevailing theory until lately was that humans arrived in North America on foot... across the Bering Land Bridge, before polar ice melted and covered it with the Bering Strait.
But that's a VERY long walk, and boats might have worked just as well. And probably did, as new evidence shows.
Our monthly underground history segment pairs us up with the researchers at the Southern Oregon University Laboratory of Anthropology (SOULA).
And this month we hear about Matthew Des Lauriers' work at Cedros Island in Baja California, finding artifacts from 13,000 years ago.
Tune in for a trip in time.