For decades, archaeologists have always believed that human beings entered America from Asia using Beringian. The person who thinks there is a continental bridge is actually Frey Jose de acosta, a Spanish missionary in the 6th century. But even if more occupation points are found in Siberia and Alaska, pointing out the human occupation and the movement from west to east, the problem still exists. When and how did immigration happen? One wave or multiple waves? Researchers from the Canadian Museum of History concluded in June, 20 17, 1 that the jawbone of a horse found in the Blue Fish Cave in Yukon was marked by human beings 24,000 years ago, which means that early Americans settled here in 22,000 BC. This delayed the date of human occupation of North America by 10000 years. However, these findings are controversial in this field and have not been generally accepted by the archaeological community.
The new report on Xach 'itee 'aanheh t 'eedegaay complicates this narrative. Although she may be "only" 1 1500 years old, she provides irrefutable evidence for the time of human migration.
In her genome is the story of a newly discovered early American group, and their ultimate fate is still a mystery, because their genes are no longer visible in modern people. Eske Willerslev, an evolutionary geneticist and one of the authors of this new study, said: "This individual represents a previously unknown group, which is also the earliest known group of Native Americans." . "We can solve some basic problems, such as when people will come to North America, because this population is related to other populations."
The upward Sun River girl was buried next to a smaller baby. They were all in the red ochre ritual tomb. She was one of the ancient whites that researchers said. Before sequencing her genome, scientists had identified two main groups of Native Americans: North American Native Americans and South American Native Americans, who split up at some point after entering the American continent. Babies do not belong to these two groups. This means that somewhere in this process, another division must have taken place, creating this unique ancient Bering language family.
Through demographic modeling, the researchers concluded that about 36,000 years ago, the founders of Native Americans began to separate from their ancestors in East Asia. By 25,000 years ago, they were completely divided. Twenty thousand years ago, there was another disagreement, this time between ancient Berliners and other Native Americans. During the next 3,000 to 6,000 years, Native Americans were further divided into two groups: North and South.
All this comes from the ancient DNA of a child who has already died.
I observed Ben Porter and Josh Lu Se, professors from the University of Alaska in fairbanks, excavating the site in the upper reaches of the Sun River. Victor Moreno Mayar, another author of the paper and a geneticist at the Center for Geogenetics, said: "Now we have these restrictions on the formation of Native Americans." . "We think the explanation for this model is that Native Americans were somewhere in Bering 20,000 years ago. The most supported archaeological site in Alaska is only 15000, so we pushed back the time, so there will be controversy. The author is well aware that this research may cause controversy. To this end, they collected two different models to explain how ancient whites came into being. In one version, whites were separated from other Native Americans before crossing the continental bridge into North America, which meant many waves of immigration. The second group, this group crossed the Bering as a group, but later split. One of the authors, archaeologist Ben Porter, supports the former.
"I tend to support this in archaeology, because it accords with most archaeological evidence we have," said Porter, who has been working in the ruins of the upper reaches of the Sun River since 2006 and discovered these children in 20 13. "This is not only a lack of sites (in Bering and North America), but also a powerful data set of sites, showing that from Northeast Asia to Aldan, to Northeast Siberia, and finally to Bering, it is about 14 years old, 500 years.
But how do two different scientific explanations coexist? Welcome to the real struggle of human history story: whose fact comes first, the fact of archaeologist or the fact of geneticist. As Porter said, genetics provides information about population and its division, while archaeology points out the physical location of these populations and their interaction with the environment. Scientists have found that they must combine these two pieces of information in a way that does not always seem consistent.
"We should remember that the earliest traces of human activities in the eastern part of Bering Island can be traced back to about 65,438+04.10,000 years ago, which makes the Sun River site too young for nearly 3,000 years." It can't be a representative of the original colonies in the New World, "Brian T. Waigal, an archaeologist at Adelphi University, said in an email. From the archaeological data alone, by the time we reached the children's tomb in the upper reaches of the Sun River, the variation of human beings in the late Pleistocene had been quite great. "
Dennis Oruk, a geneticist and archaeologist at the University of Kansas, sequenced the mitochondrial DNA of infants in the upper reaches of the Sun River several years ago, but did not participate in this research. Oruk also believes that with the increasing complexity of archaeology and genetics, there are more and more problems in this field.
"How to integrate these different types of data with past methods is a constant challenge," Oruk said. "This paper raises some questions. Archaeological and genetic data may point to different geographical groups, but I think these problems will eventually be solved by more archaeological and genomic data from different geographical regions.
This is not the first time that such a question has been raised. As Nicola Di Co *** a, an East Asian historian, wrote for the Institute of Advanced Study, "In ancient DNA research, it is quite common to explain the trend of gene distribution according to the assumed behavior patterns of certain ethnic groups and societies. In the final analysis, these assumptions can be traced back to historical, anthropological and archaeological models, and sometimes they are not the best models. " This leads to another problem of this new study: it depends on a single sample. "If we have multiple genomes, we can more accurately understand the diversity of the early Bering population," alak said.
Di-Co *** a is more straightforward. "There are very few samples from which ancient DNA information is extracted: how much do they have to do with the population movement in Eurasia for thousands of years? He wrote:
However, ancient relics are extremely rare, and even if they are found, using them in scientific research is full of ethical problems. Perhaps the most famous is Kennewick, a 9000-year-old man found in Washington. He caused a legal dispute between scientists and local indigenous groups, who wanted to rebury him. Willers Lev finally proved the genetic connection between ancient bones and modern Native Americans with DNA samples, and he was allowed to be repatriated according to the Native American Grave Protection and Repatriation Act.
Porter and other team members try to avoid any mistakes when analyzing the upward Sun River children, and cooperate with local tribes before doing any tests and trying to answer questions they may be interested in. Smithsonian Museum. Tanana Chiefs' Meeting, an alliance of 42 member tribes in Alaska, was contacted, including the area where the upper reaches of the Sun River are located, but no response was received before publication.
The team's analysis found fascinating insights. For example, Porter said that the discovery from The Rising Sun "represents the first evidence that humans use salmon in the new world". "One of the factors that we can develop through bones is that we want to observe the mother's diet and possible changes over time, which may let us know whether people store salmon in winter."
Finally, Oruk said that the most valuable knowledge in this discovery and future discoveries may be some combination of genetics, artifacts and paleoenvironmental data. Taken together, the integration of science can show how human beings create material culture to interact with the environment and survive in it.
"We always go further in one place than in another," Oruk said. "This is the challenge of how to integrate these different knowledge streams."
Editor's Note: 20 18 1.5: This article has been updated to clarify how the new paper presents different patterns of the origin of the ancient Bai people.