TThe white sands of New Mexico have been a popular tourist attraction for a remarkably long time. Modern travelers come to gaze at views of gleaming sheer gypsum dunes stretching for miles in all directions.
But the previous visitors had very different goals. A thousand years ago, Homo sapiens I came here to hunt giant sloths, mammoths, and other megafauna. In doing so, they left signs of their presence whose analysis now promises to transform our understanding of our planet’s population.
On a role in Sciences Last week, paleontologists described data suggesting that men, women and children crossed the White Sands more than 21,000 years ago. By providing that date, the team added more than 6,000 years to previous estimates of humanity’s first known appearance in the United States. Population geneticist Pontus Skoglund of the Crick Institute in London described the discovery as “absolutely revolutionary.”
For decades, it was considered that Siberian hunter-gatherers did not leave Asia, through the land now covered by the Bering Strait, to reach America until the end of the last ice age, some 15,000 years ago. Now it seems that humanity had arrived much earlier.
The evidence for this reassessment of Homo sapiens‘The last great continental conquest does not come from old stone or bone tools, but from ancient footprints preserved at White Sands. Humans walking near the lakes left wet footprints that hardened and then became covered with more sand. Thousands of these marks cross the landscape.
Fundamentally, trench seed layers were also buried for millennia. By carbon dating the seeds above and below a set of footprints, scientists were able to show that they were created between 21,000 and 23,000 years ago, long before the end of the last ice age.
Previous claims about finds that have suggested early dates for the settlement of the United States have generally been treated with skepticism. On the contrary, the fingerprint investigation has been acclaimed. They provide “a very compelling case” for an early date of humanity’s arrival in the United States, said Spencer Lucas, a paleontologist at the New Mexico Museum of Natural History and Science. Nature. “That’s a game changer.”
It’s less clear how humans managed to get to New Mexico when the last ice age was still getting worse. Those were bitterly inhospitable times, although it is possible that groups of hunter-gatherers passed through a corridor that separated the main ice sheets that then covered North America. Alternatively, they may have moved south along the west coast of the United States, possibly by boat, on a route known as the Kelp Highway.
However, there is more to this intriguing research than simply finding a new date for America’s population, the scientists emphasize. These footprints in the sands of time also have a lot to tell us about human behavior in general.
To begin with, there is the problem of the age of the people who left these traces. “Most of what we see here were made by teenagers,” says Bournemouth University Professor Matthew Bennett, lead author of the Sciences paper. “These were America’s first teenagers and they hung out together like they do today. The only thing missing then was a smartphone. “
Preserved ancient footprints have been found in many other areas and, curiously, those of young people, children and adolescents often predominate. “Older adults tend to sit still and not waste energy,” says Dr. Sally Reynolds, another member of the Bournemouth University team.
“Young people move all the time and as a consequence they leave many more footprints. It was the equivalent of parents gathering at the school gates, standing and chatting, while their children ran around the playground. “
It’s also possible that White Sands teens were helping adults track and hunt down the megafauna that roamed the region – massive creatures that would have included sloths and giant mammoths, as well as dire wolves and other animals. “The teens would have provided unskilled labor for these hunting groups,” adds Bennett.
Previous studies of other sets of tracks from White Sands, also carried out by researchers at Bournemouth University, have provided some surprisingly vivid details about the lives of people who came to the region 20,000 years ago. These snapshots of ancient lives include footprints of a woman who clearly made her way through the sand with a small child in her arms, which she left occasionally, causing small footprints to appear next to hers. It is a tender understanding of the behavior of our ancestors, which also indicates that humans were very confident of their safety in the open air.
“Humans must have established themselves quickly in White Sands,” Reynolds adds. “We evolved in Africa, where we were not apex predators. We had been the prey of others. So it’s fascinating to see that when we came to America, we had become dominant hunters. “
The dangers posed by Homo sapiens It was clearly appreciated by other animals there. One set of prints clearly shows a giant sloth avoiding a group of hunters. And that data is likely to be crucial in future explorations of the links between ancient humans and the extinction of megafauna like the mammoth.
Our ancestors are often blamed for wiping out these creatures after the end of the ice age, although other researchers suggest that climate change could have been involved as well, killing the mammoth and the giant sloth. “White Sands now gives us the opportunity to study our relationship to megafauna and gain a better understanding of what our ancestors did to these creatures,” adds Reynolds.
George is Digismak’s reported cum editor with 13 years of experience in Journalism