“Strange” – Scientists Discover Ghostly 23,000-Year-Old Human Footprints in New Mexico

Evidence buried in gypsum dunes suggests humans arrived far earlier than expected. Radiocarbon dates from three materials agree.

Vance Holliday quickly accepted an invitation to do geological research at White Sands in New Mexico. The area, located just west of Alamogordo, is known for its surreal landscape—endless rolling dunes of fine beige gypsum left behind by ancient seas. It is considered one of the most unique geological formations in the world.

However, much of the region is protected as a national park, and a nearby section is used by the U.S. Army as a missile range, which often limits access for researchers. Despite this, Holliday, an archaeologist and geologist from the University of Arizona, took the opportunity to begin research in the park in 2012. While there, he asked—more out of curiosity than expectation—if he could visit a site located 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 studying the geologic layers exposed in trenches that had been dug by earlier researchers, hoping to build a clearer timeline of the area’s history. What they didn’t realize was that just about 100 yards away, footprints preserved in ancient clay and buried beneath gypsum would soon challenge long-standing beliefs about when humans first arrived in the Americas.

Footprint discovery sparks global interest

Researchers from Bournemouth University in the United Kingdom and the U.S. National Park Service excavated the footprints in 2019 and published their findings in 2021. Although Holliday was not involved in the excavation itself, he became a co-author after data he collected in 2012 helped determine the age of the prints.

The tracks indicated that humans were present in the area between 23,000 and 21,000 years ago, a timeframe that challenges long-held beliefs about when cultures first appeared in North America. This would make the footprints roughly 10,000 years older than the remains discovered near Clovis, New Mexico, a site that defined what was long considered the continent’s earliest known culture. Since the 2021 publication, critics have questioned the findings, primarily arguing that the ancient seeds and pollen used for dating were not reliable indicators.

New study confirms original dates

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 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.”

For the latest study, Holliday and Jason Windingstad, a doctoral candidate in environmental science, returned to White Sands in 2022 and 2023 and dug a new series of trenches for a closer look at the geology of the lake beds. Windingstad had worked at White Sands as a consulting geoarchaeologist for other research teams when he agreed to join Holliday’s study.

A challenge to everything they were taught

“It’s a strange feeling when you go out there and look at the footprints and see them in person,” Windingstad said. “You realize that it basically contradicts everything that you’ve been taught about the peopling of North America.”

Holliday acknowledges that the new study doesn’t address a question he’s heard from critics since 2021: Why are there no signs of artifacts or settlements left behind by those who made the footprints?

It’s a fair question, Holliday and Windingstad said, and Holliday still does not have a peer-reviewed answer. Some of the footprints uncovered for the 2021 study were part of trackways that would have taken just a few seconds to walk, Holliday estimates. It’s perfectly reasonable, he said, to assume that hunter-gatherers would be careful not to leave behind any resources in such a short time frame.

“These people live by their artifacts, and they were far away from where they can get replacement material. They’re not just randomly dropping artifacts,” he said. “It’s not logical to me that you’re going to see a debris field.”

Even though he was confident in the 2021 findings to begin with, Holliday said, he’s glad to have more data to support them.

“I really had no doubt from the outset because the dating we had was already consistent,” Holliday said. “We have direct data from the field – and a lot of it now.”

Reference: “Paleolake geochronology supports Last Glacial Maximum (LGM) age for human tracks at White Sands, New Mexico” by Vance T. Holliday, Jason D. Windingstad, Jordon Bright, Bruce G. Phillips, Joel B. Butler, Ryan Breslawski and James E. Bowman, 18 June 2025, Science Advances.
DOI: 10.1126/sciadv.adv4951

Never miss a breakthrough: Join the SciTechDaily newsletter.
Follow us on Google and Google News.