Native Americans
Genetic evidence published in Nature is the first to show that all Native Americans can trace their ancestry back to a single migration event that happened at the tail-end of the last Ice Age. The evidence—gleaned from the full genomic profile of the six-week-old girl and the partial genomic remains of another infant—suggests the continent’s first settlers arrived in a single migratory wave around 20,900 years ago. But this population then split into two groups—one group that would go on to become the ancestors of all Native North Americans, and another that would venture no further than Alaska—a previously unknown population of ancient North Americans now dubbed the “Ancient Beringians.”
This group also split from their Asian subset. The genetic analysis, combined with computer-based population modeling, allowed the researchers to conclude that a single founding ancestral indigenous American group split from East Asians around 35,000 years ago. Then, around 20,000 years ago, this group split into two groups: the ancestors of all Native Americans, and the Ancient Beringians.
The discovery suggests two possible scenarios for the peopling of the Americas. Either two distinct groups of people crossed over Beringia (the frozen Bering Straits) prior to 15,700 years ago, or one group of people crossed over the land bridge and then split in Beringia into two groups, namely the Ancient Beringians and the Native Americans (where the latter moved south of the ice sheets 15,700 years ago). The study also reaffirms a pre-existing theory known as the “Standstill Model”—the possibility that the descendants of this single-source population were living in Beringia until about 11,500 years ago.
Regardless, it now appears that the Ancient Beringians stayed in the far North for thousands of years, while the ancestors of other Native American peoples spread throughout the rest of North America. The new genetic analysis, along with previous archaeological work, also lends credence to the idea that an offshoot of these migrants, known as the Athabascans, made their way back into the northern regions of North America again, possibly around 6,000 years ago (a process known as back migration), eventually absorbing or replacing the Ancient Beringians. More research will be required to bear this theory out.
“The differences between the genomes of the Upward Sun River infants and the genomes of other ancient Native Americans sets the Alaskan infants apart,” Gary Haynes, an anthropologist at the University of Nevada, told Gizmodo, “But there are also similarities which suggest that all the studied individuals are descendants of a single ancestral founding population. The USR population split after 20,900 years from the population that gave rise to all modern northern and southern Native Americans. The critical importance of this conclusion, if it is correct, is that it provides support for the view that a single founding population from Northeast Asia gave rise to all the native peoples of the Americas. This is a significant finding which establishes that all the pre-Columbian native peoples of the New World are members of one family tree.” (a couple of sources I can't remember)
Genetic evidence published in Nature is the first to show that all Native Americans can trace their ancestry back to a single migration event that happened at the tail-end of the last Ice Age. The evidence—gleaned from the full genomic profile of the six-week-old girl and the partial genomic remains of another infant—suggests the continent’s first settlers arrived in a single migratory wave around 20,900 years ago. But this population then split into two groups—one group that would go on to become the ancestors of all Native North Americans, and another that would venture no further than Alaska—a previously unknown population of ancient North Americans now dubbed the “Ancient Beringians.”
This group also split from their Asian subset. The genetic analysis, combined with computer-based population modeling, allowed the researchers to conclude that a single founding ancestral indigenous American group split from East Asians around 35,000 years ago. Then, around 20,000 years ago, this group split into two groups: the ancestors of all Native Americans, and the Ancient Beringians.
The discovery suggests two possible scenarios for the peopling of the Americas. Either two distinct groups of people crossed over Beringia (the frozen Bering Straits) prior to 15,700 years ago, or one group of people crossed over the land bridge and then split in Beringia into two groups, namely the Ancient Beringians and the Native Americans (where the latter moved south of the ice sheets 15,700 years ago). The study also reaffirms a pre-existing theory known as the “Standstill Model”—the possibility that the descendants of this single-source population were living in Beringia until about 11,500 years ago.
Regardless, it now appears that the Ancient Beringians stayed in the far North for thousands of years, while the ancestors of other Native American peoples spread throughout the rest of North America. The new genetic analysis, along with previous archaeological work, also lends credence to the idea that an offshoot of these migrants, known as the Athabascans, made their way back into the northern regions of North America again, possibly around 6,000 years ago (a process known as back migration), eventually absorbing or replacing the Ancient Beringians. More research will be required to bear this theory out.
“The differences between the genomes of the Upward Sun River infants and the genomes of other ancient Native Americans sets the Alaskan infants apart,” Gary Haynes, an anthropologist at the University of Nevada, told Gizmodo, “But there are also similarities which suggest that all the studied individuals are descendants of a single ancestral founding population. The USR population split after 20,900 years from the population that gave rise to all modern northern and southern Native Americans. The critical importance of this conclusion, if it is correct, is that it provides support for the view that a single founding population from Northeast Asia gave rise to all the native peoples of the Americas. This is a significant finding which establishes that all the pre-Columbian native peoples of the New World are members of one family tree.” (a couple of sources I can't remember)
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