In 2019, ancient footprints were excavated in New Mexico that appeared to reset the timeline of human activity in the Americas. After several years of debate, a University of Arizona researcher has led a study that supports the ground-breaking findings.
The UA’s Vance Holliday had conducted previous research at White Sands National Park, where the footprints were found. His data helped date the footprints, which indicated human activity occurred in the area between 21,000 and 23,000 years ago — 10,000 years earlier than previously known.
But Holliday says critics challenged the use of seeds and pollen to date the footprints.
“That's a potential problem. It's known. But it's making the assumption that those plants are taking up water that has this old carbon. And then with the pollen, there was a criticism that, well, maybe this pollen is old pollen," said Holliday.
The new study led by Holliday used ancient mud to carbon-date the footprints themselves, and confirms the new timeline.
“So we had this confirmation or support of that original dating, plus we had this whole new look at what the paleolandscape was like," he said.
The study was published in the journal Science Advances.
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