Recently discovered human footprints at the bottom of an ancient lake in the southern United States suggest that people already inhabited North America during the last glacial maximum and did not come from Asia after the glaciers retreated, as previously thought. The results of the study are published in the journal Science.
To date, there is no consensus among scientists about the time of the appearance of the first people on the American continent. Traditionally, it is believed that ancient people came to North America from Asia, using the Bering Isthmus — a strip of land that arose on the site of the modern Bering Strait about 13 thousand years ago.
However, recently there have been many new facts proving that the first people came to America much earlier — in the late Pleistocene, 25-20 thousand years ago when Eurasia and America were connected by a land area known as Beringia. Ancient people could likely have used this earlier corridor to migrate from Asia.
Scientists were confused by only one factor — at that time, Beringia was covered with ice. Further, on the way to the south, the first Americans had to overcome a huge territory located in the Arctic climate zone to reach warm latitudes.
Proponents of the “early settlement” hypothesis suggest that the settlers used a non-freezing corridor along the western coast of North America to migrate to the south. However, this path was blocked by ice during the Maximum of the last glaciation, which took place 26-19 thousand years ago. So, if there was an early settlement, it occurred before the onset of the maximum glaciation.
Now the supporters of such a hypothesis have new arguments. At the bottom of an ancient lake in the White Sands National Park in New Mexico, American and British archaeologists led by Matthew Bennet from the Institute for Research on Landscapes and Human Evolution at Bournemouth University found a large number of fossilized human footprints stratigraphically dated to layers of sediments aged 23-21 thousand years.
“Unlike cultural artifacts or other evidence of human activity, the origin of which may be uncertain, the traces have a primary context of finding, are fixed on the printed surface and are tied to a specific moment in time,” the authors of the article write.
Most of the tracks were left by teenagers and children; traces of adults are much less common.
According to the authors, the results not only provide definitive evidence of the antiquity of the colonization of the New World but also indicate that ancient people reached the south of North America before the glaciers of the Maximum of the last glaciation blocked the migration path from Asia.