Evidence from ancient footprints shows that humans lived in the Americas earlier than previously thought
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Researchers have found evidence that suggests humans first arrived in North America around 21,000 years ago. This has been a hot topic of debate for many researchers. New Mexico's analysis of fossilized footprints from ancient humans has proven that the date is at least 21,000 years old.
A team of scientists led by Matthew Bennett from Bournemouth University, England, published their findings in Science. They examined the footprints of humans on an ancient lakeshore in New Mexico's White Sands National Park. This location is well-known for its large, chalk-colored dunes.
They concluded that footprints were made between 21,000-233,000 years ago. This date would put human habitation in Americas during The Last Glacial Maximum, which is at least 5,000 years before the evidence suggests.
Most footprints were made by teenagers and children.
Bennett and his coworkers determined that the tracks belonged mostly to children and teens. Their paper was published on Thursday. The footprints also covered a considerable time period, which suggests that human beings have been in the area for at most a few thousand year.
According to Science News Bennett, "One of the most beautiful things about footprints, unlike stone tools and bones, they cannot be moved up or down stratigraphy," Bennett said. This refers to the layers in which fossils and artifacts can be found. They are fixed and very precise.
Bennett, an environmental and geographic sciences professor, said that rock layers are usually "a nightmare to date". He says that two-years ago, David Bustos, an archaeologist and study co-author, found a site in which human footprints had been mixed with sediment that contained seeds from the spiral ditchgrass. This aquatic plant could be carbon-dated. These results provided an estimate of the footprints.
Tom Higham, an archaeologist and radiocarbon-dating expert at University of Vienna, called the new findings "extremely interesting."
He stated, in accordance with Nature, "I am convinced these footprints are genuinely of the age claimed."
Less solid evidence is available for earlier dates of Americas migration.
Nature claims that previous studies, including one in 2017 which suggested that humans moved to North America earlier than expected, have been widely dismissed due to the "equivocality" of the evidence. The journal states that rocks were mistakenly thought to be tools, and that marks on bones of animals believed to have been made by humans turned out to be natural.
Vance Holliday is an archaeologist at the University of Arizona and coauthor of the paper. "Archaeologists have been debating for decades when humans first arrived in Americas," he says. "Very few archaeologists have evidence that sites are older than 16,000 years. Some believe the Clovis points artifacts were made 13,000 years after the arrival of the Clovis points.
Nature published last year a paper written by archaeologists claiming to have discovered human artifacts in Mexico’s Chiquihuite Cave. The discovery was made at least 26,000+ years ago. Many archaeologists were skeptical of the claims that the tools they identified were stone tools.
Ciprian Ardelean was the leader of the 2020 study at Chiquihuite and readily acknowledged that Bennett's discovery "is very close" to the Holy Grail.
Ardelean said to National Geographic, "I feel a healthy and profound envy, a good sort of jealousy towards team for finding such an thing."
