White Sands National Park has some of the most archaeologically rich sand in North America, and it is within this New Mexico landscape that the oldest footprints ever found on the continent were discovered. Recent research now dates those footprints to roughly 23,000 years old—about 10,000 years before it was previously believed humans existed in North America.
“The site in New Mexico has rewritten history books as we’ve discovered wonderful examples of human activity, the way that humans interacted with one another, with the landscape, and with the animal life there,” Sally Reynolds, principal academic in paleoecology at Bournemouth University, said in a statement. “These footprints provide a valuable window into the lives our ancestors lived and how much they were like us.”
Previously believed to be about 13,000 years old, a study in 2021 by U.S. Geological Survey researchers instead dated the footprints to about 23,000 years ago using radiocarbon datingmethods. The team wanted to confirm those findings, though, and published another study in the journal Science in late 2023 that confirmed the newly “calibrated” aging of the footprints with the dating of fossilized pine pollen.
With pollen and common ditch grass seed found both in the footprints and within the same layer of hardened mud in which the footprints were found, the team was able to confirm the new 23,000-year-old date, showing that humans were on the continent during the Last Glacial Maximum. The team also used optical stimulated luminescence to look at background radiation in quartz. The more energy in the quartz, the older the find. This helped corroborate the date.
Matthew Bennett, a Bournemouth University professor and co-author of the study, said in a statement that the team was pleased that after the initial study was investigated further, they were able to provide new results that “underline the accuracy of our original study and provide a fascinating update to the movements and lifestyles of our ancestors.”