Ice Age human footprints found fossilized in the ground at White Sands National Park in New Mexico are rewriting the history of humans in America.
Scientists announced on Thursday that the footprints are 23,000 years old, which means they were left during the last Ice Age.
The results have rekindled the question of how humans first arrived in the Americas. The footprints seem to suggest that these early travelers spread across the continent when it was mostly comprised of glaciers and ice.
“I think this is probably the biggest discovery about the peopling of America in a hundred years,” said Ciprian Ardelean, an archaeologist at Autonomous University of Zacatecas in Mexico, who is not a researching the footprints. “I don’t know what gods they prayed to, but this is a dream find.”
The footprints are notable for bolstering the argument of researchers who believe that humans actually arrived in the Americas at the onset of the Ice Age. The dominant belief amongst archaeologists for decades had been that people spread across North and South America as the last Ice Age was nearing its end.
They backed up their argument with the oldest known tools that had been discovered in the continent, including spear tips, needles and scrapers, which were found to be 13,000 years old. The artifacts were referred to as “Clovis,” the name of the area in New Mexico where they were first uncovered.
Scientists were particularly swayed by this argument because the age of the Clovis artifacts aligned perfectly with the end of that Ice Age. From this they developed the narrative in which Siberian hunter-gatherers came to Alaska during the Ice Age and stayed there for decades until the glaciers receded and gave them the ability to move south into the rest of the continent.
But other researchers began to cast doubts on these beliefs in the 1970s. Archeologists started to publish evidence suggesting that humans were present in North America much earlier than people believed. Archaeologist Ciprian Ardelean and his colleagues had published a report as recently as last year that detailed stone tools from a cave in Mexico were 26,000 years old.
But other archeologists have challenged these reports. Ben Potter, an archeologist at the Arctic Studies Center in Liaocheng University in China, said that he believed that those “tools” could easily be misshapen rocks that the researchers mistook for intentional man-made objects. Potter also said that the dates the archaeologists attributed to their finds could be dubious. Potter said that tools and artifacts that merge with underlying sediment can seem older than they are.
Footprints found at White Sands National Park offer more definitive evidence of early human activities
But the study out of White Sands National Park brings a different kind of evidence to the table, one that is less prone to error than artifacts and tools: footprints.
The footprints were discovered in 2009 by David Bustos, the resource program manager at White Sands National Park. Bustos had a team of international scientists come to the location to analyze the prints.
The team has found thousands of footprints throughout the 80,000 acre park during their time working with Bustos. They have found footprints that show a mother resting her baby on the ground, others that were made by a person walking in a perfectly straight line for over a mile, and others that appear to belong to children.