New research suggests the ancestors of the earliest Native Americans took a pretty extensive pit stop while crossing a land bridge to the Americas from Asia 25,000 years ago. And by extensive, I mean, like, a 10,000-year-long pit stop.
The new theory stems from a gap in the history of those early humans. Scientists believe Native American ancestors broke away from their Asian relatives 25,000 years ago, but the earliest evidence of people in the Americas date back to only 15,000 years ago. So, what were they doing? (Via History Channel)
Apparently having a massive campout. According to National Geographic, scientists thought the land bridge, also known as Beringia, was incapable of supporting a large human population.
But more recently, paleoecologists found sediment in the Bering Sea that indicated the land bridge's environment was dotted with foliage.
Dennis O'Rourke, one of researchers of the new finding, said Beringia "was an environment with trees and shrubs that was very different than the open, grassy steppe. It was an area where people could have had resources, lived and persisted through the last glacial maximum in Beringia." (Via The University of Utah)
O'Rourke and his colleagues also point to a study of mitochondrial DNA that shows the DNA of Native Americans is distinct from their Asian ancestors. He added, "This result indicated that a substantial population existed somewhere, in isolation from the rest of Asia, while its genome differentiated from the parental Asian genome." (Via Nature World News)
A writer for iO9 suggests maybe the land bridge was misnamed, seeing how this new theory makes it sound more like a home rather than just some expansive passageway.
But O'Rourke hypothesizes that those traveling across Beringia could've been trapped by ice during the glacial maximum period, when ice sheets on Earth were at their maximum extension. When the ice melted, those humans spilled into North America.
O'Rourke, and the three other authors of the study, make their argument without presenting any archeological evidence because the entire region is now underwater.
But they say evidence of human habitation could be found in low-lying portions of Alaska and Northeastern Russia. (Via NASA)
The article titled "Out of Beringia?" was authored by researchers at the University of Colorado Boulder, Royal Holloway University in London and the University of Utah. It's published in the journal Science.