A controversial study suggests that the 15,600 year old print is the oldest human footprint ever found in the Americas

An apparent human footprint discovered by archaeologists in Chile has been dated to 15,600 years, making it one of the oldest engravings ever found in the New World. It's an intriguing discovery that suggests an early human settlement in South America, but not everyone is convinced by the new evidence.

The only copy was discovered in 2011 on the archaeological site of Pilauco in the Chilean city of Osorno. This site was the subject of excavations from 2007 to 2016, which allowed to discover various animal bones, plant material, simple stone tools and this apparent human footprint. The discovery is particularly significant because of the scarcity of ancient footprints in the Americas and a longstanding debate about the settlement of South America at the Late Pleistocene. The new study, led by paleontologist Karen Moreno and geologist Mario Pino of the Austral University in Chile, was published last week in PLOS One.

Other significant footprints in the Americas include 14,600-year-old trails in nearby Monte Verde and a pair of 10,700-year-old and 7,200-year-old trails in Mexico. Last year, archaeologists discovered 29 human footprints on the coastline of Calvert Island, British Columbia, dated from 13,000 years ago. Monte Verde's engravings are the oldest evidence of a human presence in South America, even though they remain controversial. The fact that a human footprint has now been found about 100 kilometers from the Pilauco site, dating to about the same time as Monte Verde, reinforces the case that humans lived in South America at this time. time. But at 15,600 years old, it would be the oldest engraving ever found on the American continent. This is obviously a big problem.

For analysis, Moreno and Pino radiocarbon dated organic plant materials are found in the same layer as the solitary footprint. Measurements done by hand, a plaster reconstruction and a series of X-ray images allowed researchers to analyze the fingerprint in detail. They estimated that the impression had been made by a barefoot man weighing about 70 kg (155 pounds). Because of its size, shape and level of preservation, Pilauco's footprint "corresponds to a right foot impression of an adult human being," and not to any other animal, such as the A lazy floor, wrote the authors in this new study.

As the new paper has pointed out, the impression has been attributed to the species of ichnospecia. Hominipes modernus (with ichnospecies describing a distinct fossil trace). The researchers believe that the fingerprint was made by Homo sapiens, no evidence has ever suggested that a human species other than Homo sapiens never done for the Americas.

Moreno and Pino also conducted an experiment to test different imprinting scenarios. The team extracted soil samples from Pilauco, rehydrating the sediments with different amounts of water. Three individuals, all with body proportions consistent with the alleged runway manufacturer, were recruited to cross a test bench containing the soggy mixture. "Results demonstrate that a human agent can easily generate a fingerprint [shape] equivalent to the sedimentary structure when walking on a saturated substrate ", wrote the authors of the study.

That said, researchers do not understand why only one footprint was recovered and not an entire track. They cited the sediment mixture over time as a probable cause.

But Stuart Fiedel, an archaeologist with the consulting firm Louis Berger Group, interpreted the new research differently. Fiedel does not believe that the footprints found in Monte Verde or Pilauco's are true human footprints.

"If you compare these two bean-shaped depressions and real old human footprints, you'll notice that the outer edge of the actual footprints is still straight and does not bend from heel to feet like the Monte Verde. and impressions of Pilauco, "Fiedel told Gizmodo. "This difference can be seen even in the prints produced experimentally presented in the article."

In addition, the authors seem to interpret the protrusion as the impression left by a big toe. But this "is not the normal morphology of human toes," he said. The authors do not explain convincingly why there is a lump in the middle of the "sole", added Fiedel.

According to Fiedel, the apparent stone tools found near the fingerprints are not really tools, but "simply pebbles broken without any proof of manufacture by a human". "About 16,000 to 15,000 years ago.

Fiedel said that he thought the print could have been made with a piece of rotten wood, and noted that there were pieces of wood of similar size and shape to those found at proximity.

Nicholas Felstead, from Swansea University, said the new document was interesting, explaining to Gizmodo that "the reliable radiocarbon dates obtained by the authors make this finding very convincing". Indeed, there is a great debate about when humans have populated the Americas, the two main theories being the Pacific Coastal Highway hypothesis (also known as the Pre-Clovis theory) and the Clovis First.

"Archaeologists at Clovis First believe that the first humans, the Clovis people, arrived in the Far North about 14,000 years ago, when the ice sheets withdrew enough to allow Alaska's passage into the North. the states of the northern US "affiliated with the new study, wrote in an email to Gizmodo. "The mainstay of this theory is that there is no solid evidence for pre-Clovis humans in the Americas. It became the standard model of how and when the first humans arrived on the American continent. "

However, as Felstead pointed out, other archaeologists believe that humans have traveled the Pacific coast of the Americas much earlier than 14,000 years ago and much faster. Monte Verde in Chile is probably the most famous site linked to the Pacific Rim Road, with footprints dating back about 14,600 years old – but these footprints are highly controversial in the debate, he said.

"These new footprints are important because they provide further evidence of human presence prior to Clovis in the Americas," Felstead said. "If it's a human well, these footprints provide compelling evidence to support the Pacific Rim migration route."

Given the great claim of Moreno and Pino and the ambiguity of the unique print and the nature of the artifacts found on the site, it would be useful to ask a second research team to find out more. examine the evidence available. Until then, the debate about when humans first settled in South America will continue to rage.