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Darrin Lowery found a collection of tools in Maryland that may date back 22,000 years.
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That would mean that humans first arrived in North America thousands of years before we thought.
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Most experts believe that humans first arrived in North America between 15,000 and 20,000 years ago.
North and South America were the last inhabited continents where modern humans settled thousands of years ago, but when and how they reached the Americas remains a mystery.
“We don’t know who these first peoples were,” Todd Braje, executive director of the University of Oregon Museum of Natural and Cultural History, told Business Insider. We don’t know “where they came from, when they arrived, what technologies they had at their disposal,” he added.
For years, archaeologists believed that the first humans to set foot in the Americas did so about 13,000 years ago. But more recently, new findings have cast doubt on this theory, pushing the timeline back even further.
Now, a recent series of discoveries on Parsons Island, Maryland, could turn back the clock again. And it raises some tough questions about early human migration across North America.
Outside the mainstream
Darrin Lowery has been hunting for artifacts on the Maryland Islands around the Chesapeake Bay since he was 9 years old. More than forty years later, he has amassed a large collection of tools that he believes were used by some of the first Americans.
He found nearly 300 tools on Parsons Island and says they are about 22,000 years old. That’s thousands of years before many scientists think humans first traveled to North America.
If Lowery’s hypothesis is correct, it would significantly change our ideas about how and when humans arrived in this part of the world.
However, Lowery, who works primarily as an independent geologist, has not published his latest work in a peer-reviewed journal, leaving other experts skeptical of a theory that is already somewhat outside the mainstream.
Lowery, however, doesn’t mind the criticism. “If I’m wrong, that’s fine with me,” he told Business Insider. “Prove me wrong.”
When did the first modern humans reach North America?
About 13,000 years ago, something important happened in northern North America: the glaciers that had covered part of the continent for millennia were melting.
Archaeologists thought people had to wait until those glaciers melted to migrate through this region. Otherwise the journey through what is now Canada would have been too dangerous, as there was little food available along the way.
So for most of the 20th century, the theory was that the first Americans emerged from Asia about 13,000 years ago, crossing the now submerged Bering land bridge that connected Siberia to present-day Alaska. Then those people and their ancestors moved through areas of the Americas with fewer glaciers.
But by the second half of the 20th century, older sites emerged, such as a 14,500-year-old site in Chile, Monte Verde. If people lived that far south at the time, it meant that humans must have traveled from North America to South America more than 13,000 years ago.
“It really changed everything about what we understood about when and how people came to America,” Braje said of the Chile site. An alternative theory is that people followed the less frigid Pacific coast and then moved east.
Although individual locations are often the subject of debate, the generally accepted range of humans’ first arrival in the Americas is now between 20,000 and 15,000 years ago, Braje said.
But Lowery said his artifacts are even older.
Dating of 22,000 year old artifacts
During 93 visits to Parsons Island, Lowery and other volunteers found a mix of broken rock flakes, a hammering stone and knives.
Due to erosion, most of the artifacts fell from the embankment they once stood on.
However, nine of them were still stuck in the bank, and three of them dated from about 22,000 years ago.
Dating these types of ancient artifacts is tricky and is often the source of debate surrounding these sites that question our understanding and timeline of ancient human history.
For example, most dating methods require organic material and do not work on stone tools. Instead, scientists test charcoal, pollen, and other materials found near stone artifacts.
However, if a tool shifts from its original position (for example, if it falls from the embankment it is attached to), it is difficult to date it reliably.
Therefore, only a handful of Lowery’s artifacts could be tested.
Although Lowery would not publish a paper through peer review — a process he called “outdated” — he said he had done his best to date the artifacts.
He used various methods to date the artifacts still present and also sent samples to independent laboratories for verification.
Using radiocarbon dating, which measures the amount of carbon in charcoal flakes, an independent laboratory estimated the age of the artifacts to be between 20,563 and 22,656 years old.
If these artifacts are as old as laboratory analysis suggests, Lowery’s discovery could rewrite our understanding of ancient American human history.
The journey from Alaska to Maryland
About 21,000 years ago, almost all of Canada was covered in glaciers. That’s why one of the biggest questions about Lowery’s theory is how humans were able to make the journey from Alaska to Maryland 22,000 years ago, when there was still a vast, icy landscape in between.
But Lowery said Beringian wolves traveled through a temporary corridor between ice sheets nearly 26,000 years ago. People could have used the same route, he said.
“I think this is largely a misconception that ice is a hindrance,” Lowery said. “It’s a challenge, but people are pretty damn smart.”
Lowery admitted that this is exactly what he called “a story,” but it’s a story that some experts refuse to entertain. One archaeologist The Washington Post spoke to declined to comment on the non-peer-reviewed article.
For Braje, Lowery’s research is reminiscent of past debates, when new discoveries pushed back the timeline for the first American arrivals.
Braje hasn’t rejected Lowery’s ideas outright, but he believes they should go through the peer-review process. “I think all these ideas are valid that we should be talking about,” he said, “but then we have to go to the scientific evidence.”
“Making such big claims takes a lot of work, a lot of evidence and a lot of sustained criticism, but that’s part of the scientific process,” says Braje.
Read the original article on Business Insider