The standard story of the peopling of the Americas has Asians migrating across a land bridge into Alaska some 14,000 years ago, after Ice Age glaciers melted back, and gradually spreading southward across a land never before occupied by humankind.
But the claim in 2021 that human footprints discovered in mud in what is now New Mexico were between 23,000 and 21,000 years old turned that theory on its head.
Now, a new analysis of these footprints, using two different techniques, confirms the date, providing seemingly incontrovertible proof that humans were already living in North America during the height of the last Ice Age.
The study, led by a team of researchers at the U.S. Geological Survey (USGS) and co-authored by David Wahl, a UC Berkeley adjunct associate professor of geography and a USGS scientist specializing in pollen analysis, was published today in the journal Science.
"When the original paper was published in 2021, the authors were very cautious about claiming a paradigm shift, which is what this is all about," Wahl said. "I mean, if people were here 7,000 years prior to the Clovis culture, why don't we see more evidence?