The transition from Asia, the first Americans have got into an unknown


Nearly 11,000 years ago, a man died in what is now Nevada. He was buried in a blanket for rabbit and cod skin, buried in a place called the Spiritual Cave.

Now, scientists have discovered and analyzed their DNA, along with those of 70 other old people whose remains have been discovered throughout America. The findings give a surprising detail to a story that was once lost in prehistoric times: how and when people spread across the western hemisphere.

The earliest known arrivals from Asia have already split into distinctly distinct groups, according to research. Some of these populations have thrived and become the ancestors of indigenous peoples throughout the hemisphere.

But other groups completely disappeared, leaving no traces left, which can be detected in ancient DNA. New genetic research suggests a number of dramatic chapters in humans that archeology has not yet discovered.

"Now, that's archaeologists," said Ben Potter from the University of Alaska, who did not take part in new documents. "Holy cow, that's great."

Previous studies have shown that people moved to America at the end of the last ice age, traveling from Siberia to Alaska over a land bridge that is now beneath the Bering Sea. They extend to the south, eventually reaching the summit of South America.

Until recently, geneticists would have little insight into these large migrations. Five years ago, only one human genome was recovered in the western hemisphere, discovered by a 4,000-year-old man in Greenland.

The latest series of analyzes, published in three separate studies, is a turning point. In the past few years, researchers have restored the genomes of 229 old tooth and bone people discovered throughout America.

"It's basically an explosion," said Dr. Willerslev.

A man from the Spiritual Cave in Nevada belonged to this southern branch of migrants. He was also closely affiliated with the 12,700-year-old boy who was on the other side of the Rocky Mountains in Montana. Willerslev.

In his new study, dr. Reich and his colleagues did not find a trace of the Y population – but the dr. Willerslev succeeded in identifying his DNA in some 10,400-year-old skeletons in Brazil.

"A little million dollars is a clear question, how did this happen?" Dr dr. Willerslev.

Perhaps the second group of Asians entered America long before the ancestors of the Man from the Spiritual Cave and other early natives. Perhaps they intertwined with people in the Amazon before they completely disappeared.

Or maybe some of the first members of the southern branch had some strange genes that survived through generations.

The new tendency of genetic patterns reflects an improvement in the relationship between scientists and indigenous peoples. For many decades, many tribes have rejected the request for DNA researchers.

For example, a man from the Spiritual Cave was excavated and stored in the museum by archaeologists in 1940. The Fallon Paiute-Shoshone local tribe did not learn about the body until 1996. They fought for their repatriation years.

"It's completely disrespectful," said Rochanne L. Downs, a member of the tribal culture board. "If someone went to the Arlington cemetery and dug up the tomb of one of the soldiers and took away his medals, it would be bitter."

At the beginning, the tribe opposed the search for DNA in the skeleton, because scientists would have to destroy much. Dr. Willerslev met with the tribe and explained that he would only need a tooth and a small piece of ear bone.

The tribes agreed to give him one shot in search of DNA in the remains of the Spiritual Cave.

Results of dr. Willerslev led the Land Administration Office to turn the skeleton to the tribe. Last year they buried a man from the Spiritual Cave in an undisclosed location.

Mrs Downs would not exclude similar studies in the future, but every request should require careful consideration.

"Everything will depend on the case-by-case," she said. "The main thing is our respect for the remains."

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