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Despite nearly a century of research and heated debate on the earliest evidence of human settlement in the Americas, details about the migration of early human communities to the New World and its impact on the Pleistocene landscape remain poorly understood. Now however the discovery of a set of 60 human footprints in the bed of an ancient lake offers new scientific evidence on how early man first set foot in America.
Up to now, current estimates place the earliest evidence of the presence of man on the American continent in a period between 13,000 and 20,000 years ago.
The imprints now found in today’s territory of the White Sands National Park, in New Mexico, nevertheless locates this presence between 21,000 and 23,000 years ago. This shows that humans were already on the continent before the Last Glacial Maximum, the time during the last glacial period of our planet in which the ice reached its maximum extension preventing human migration from the Asian continent.
“Archaeologists and researchers in related fields have long sought to understand the human colonization of North America. When, how and from where people migrated, as well as what were the consequences of their arrival for the fauna and the local landscape, are some recurring questions “, Explain Matthew Bennett, Professor of Environmental and Geographical Sciences at Bournemouth University and lead author of the article entitled Evidence of humans in North America during the Last Glacial Maximum is published this week in the magazine Science.
Routes between the ice of America
During the maximum extent of glaciers from the last ice age, between about 26,500 and 19,000 years ago, the land connected Russia and Alaska, allowing people to settle in the now mostly submerged region that archaeologists know as Beringia.
Nevertheless, throughout this period of time glaciers covered much of Canada, blocking the way to the south; what is now the continental United States. Archaeologists once thought that the first people came to the Americas by walking down a corridor that opened between the glaciers about 13,500 years ago.
In recent decades, however, data from several other sites have suggested that man had already arrived on the continent at least 16,000 years ago, leading many researchers to suspect that the first humans to arrive skirted the ice while traveling. along the Pacific coast by boat.
“In most cases, the timeline of human expansion into North America is constrained by the feasibility of currently recognized migration routes from Asia: an ice-free inland corridor through western Canada and a coastal route into the Peaceful”explains Bennet.
“Most likely, both were closed or extremely difficult to traverse during the Last Glacial Maximum.”, Add. But according to the authors, unlike cultural artifacts or other evidence of human activity, which may have an uncertain provenance, theThe footprints found have a clear context. Fixed on the printed surface, they represent an exact moment in time.
On the trail of the first settlers
To find out the age of the prints, the researchers radiocarbon dated the seeds embedded in various layers of soil at the site of the discovery. The dating placed the seeds between approximately 23,000 and 21,000 years ago, during the height of the last ice age.. If the tracks are that old, humans had to reach the mainland before ice sheets blocked the way, meaning that an early overland journey may have been possible.
Further analysis of the footprints also suggests that most were made by teenagers and children who perhaps were fetching water or simply hanging out. “People spend a lot of time playing. And what better place to play than on the edge of a lake? These findings confirm the presence of humans in North America during the Last Glacial Maximum, providing new evidence for the antiquity of human colonization of the New World and providing an extension of the time range of up to 3,000 years for the coexistence of the first inhabitants. and the megafauna of the Pleistocene “, concludes Bennet.
However, given the magnitude of the find, scientists continue to try to refute their new discovery, for example by verifying that the chemistry of the water of the ancient lake did not skew the data obtained by radiocarbon dating. An annoying possibility is that the seeds are older than the footprints, which is why several geologists unrelated to the investigation suggest dating them by optically stimulated luminescence For the sake of securing even more dates offered by the Bennet team.
Source: Héctor Rodríguez / National Geographic,
Reference article: https://www.nationalgeographic.com.es/ciencia/seres-humanos-pudieron-llegar-a-america-antes-que-se-pensaba_17361,
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