Geologist clinches that humans have been in New World far longer than "Clovis First"

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BACKGROUND (wikipedia): White Sands footprints
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Earliest evidence of humans in the Americas confirmed in new U of A study
https://www.eurekalert.org/news-releases/1087664

INTRO: Vance Holliday jumped at the invitation to go do geology at New Mexico's White Sands. The landscape, just west of Alamogordo, looks surreal – endless, rolling dunes of fine beige gypsum, left behind by ancient seas. It's one of the most unique geologic features in the world.

But a national park protects much of the area's natural resources, and the U.S. Army uses an adjacent swath as a missile range, making research at White Sands impossible much of the time. So it was an easy call for Holliday, a University of Arizona archaeologist and geologist, to accept an invitation in 2012 to do research in the park. While he was there, he asked, skeptically, if he could look at a site on the missile range.

"Well, next thing I know, there we were on the missile range," he said.

Holliday and a graduate student spent several days examining geologic layers in trenches, dug by previous researchers, to piece together a timeline for the area. They had no idea that, about 100 yards away, were footprints, preserved in ancient clay and buried under gypsum, that would help spark a wholly new theory about when humans arrived in the Americas.

Researchers from Bournemouth University in the United Kingdom and the U.S. National Park Service excavated those footprints in 2019 and published their paper in 2021. Holliday did not participate in the excavation but became a co-author after some of his 2012 data helped date the footprints.

The tracks showed human activity in the area occurred between 23,000 and 21,000 years ago – a timeline that would upend anthropologists' understanding of when cultures developed in North America. It would make the prints about 10,000 years older than remains found 90 years ago at a site near Clovis, New Mexico, which gave its name to an artifact assemblage long understood by archaeologists to represent the earliest known culture in North America. Critics have spent the last four years questioning the 2021 findings, largely arguing that the ancient seeds and pollen in the soil used to date the footprints were unreliable markers.

Now, Holliday leads a new study that supports the 2021 findings – this time relying on ancient mud to radiocarbon date the footprints, not seeds and pollen, and an independent lab to make the analysis. The paper was published today in the journal Science Advances.

Specifically, the new paper finds that the mud is between 20,700 and 22,400 years old – which correlates with the original finding that the footprints are between 21,000 and 23,000 years old. The new study now marks the third type of material – mud in addition to seeds and pollen – used to date the footprints, and by three different labs. Two separate research groups now have a total of 55 consistent radiocarbon dates.

"It's a remarkably consistent record," said Holliday, a professor emeritus in the School of Anthropology and Department of Geosciences who has studied the "peopling of the Americas" for nearly 50 years, focusing largely on the Great Plains and the Southwest.

"You get to the point where it's really hard to explain all this away," he added. "As I say in the paper, it would be serendipity in the extreme to have all these dates giving you a consistent picture that's in error."

Millennia ago, White Sands was a series of lakes that eventually dried up. Wind erosion piled the gypsum into the dunes that define the area today. The footprints were excavated in the beds of a stream that flowed into one such ancient lake.

"The wind erosion destroyed part of the story, so that part is just gone," Holliday said. "The rest is buried under the world's biggest pile of gypsum sand." (MORE - details, no ads)

[Yazata]

Evidence is accumulating that humans arrived in the Americas (both North and South) as early as 30,000 years ago. I like the theory advanced by Cavalli Sforza that humans arrived in the Americas in several waves, associated with the ice ages.

He hypothesized that the first wave arrived early in the last ice age about 30,000 years ago when conditions at the Bering land bridge weren't yet so severe as to prevent people from crossing. This initial wave spread throughout the Americas all the way to the bottom of South America fairly quickly, in just a few thousand years. They are the ancestors of most of the American Indians.

The second wave arrived about 10,000 years ago as the ice age was ending and the land bridge was passable again. They are ancestors of the Na-Dene language family in Canada and the American southwest.

And the third and most recent wave were the Eskimos and Aleuts.

While subsequent research might challenge many details, I do believe that the peopling of the western hemisphere probably did occur in several waves, the first of which was much earlier than Clovis.