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Humans Arrived in North America Nearly 10,000 Years Earlier than Past Estimates: Study
Humans arrived in North America nearly 14,000 years ago as per earlier estimates but a new research conducted by researchers from Université de Montréal' and University of Oxford claims that humans might have reached North America around 24,000 years ago. The study team made these claims after evaluating animal bones found in the northwestern Yukon's Bluefish caves in Canada. The bones have imprints from human-made tools. Some of the bones found in the northwestern Yukon's Bluefish caves are as old as 24,000 years. These bones were found between 1977 and 1987, and have been dated by researchers in the past as well.
The research team conducted an exhaustive review of bone fragments. Research team members Ariane Burke said that there are clear cut-marks created by human tools on some of the bone fragments.
Many research papers published in the past have offered estimate of humans moving North America across the Bering Strait. Ariane Burke, a professor in Université de Montréal's Department of Anthropology, and her doctoral student Lauriane Bourgeon worked on the current project. They were helped by Dr. Thomas Higham, Deputy Director of Oxford University's Radiocarbon Accelerator Unit. The research team worked on the project for nearly two years.
The bone fragments have been preserved at the Canadian Museum of History in Gatineau. The details of current study have been published in the journal PLoS One. The study was funded by the Fonds de Recherche Québécois Société et Culture.
The research paper informed....
In the absence of other sites of similar age, Cinq-Mars' hypothesis remained highly controversial in the scientific community. Moreover, there was no evidence that the presence of horse, mammoth, bison and caribou bones in the Bluefish Caves was due to human activity.
To set the record straight, Bourgeon examined the approximate 36,000 bone fragments culled from the site and preserved at the Canadian Museum of History in Gatineau -- an enormous undertaking that took her two years to complete. Comprehensive analysis of certain pieces at UdeM's Ecomorphology and Paleoanthropology Laboratory revealed undeniable traces of human activity in 15 bones. Around 20 other fragments also showed probable traces of the same type of activity.
Bourgeon submitted the bones to further radiocarbon dating. The oldest fragment, a horse mandible showing the marks of a stone tool apparently used to remove the tongue, was radiocarbon-dated at 19,650 years, which is equivalent to between 23,000 and 24,000 cal BP (calibrated years Before Present).
"Our discovery confirms previous analyses and demonstrates that this is the earliest known site of human settlement in Canada," said Burke. It shows that Eastern Beringia was inhabited during the last ice age."
Beringia is a vast region stretching from the Mackenzie River in the Northwest Territories to the Lena River in Russia. According to Burke, studies in population genetics have shown that a group of a few thousand individuals lived in isolation from the rest of the world in Beringia 15,000 to 24,000 years ago.
The Beringians of Bluefish Caves were therefore among the ancestors of people who, at the end of the last ice age, colonized the entire continent along the coast to South America.