A genetic study has put an end to the issue of the origin of Native Americans. They both came to the continent from Chukotka, and their closest relatives were Yakuts and Nenets. This happened probably 12 thousand years ago, when the site of the present Bering Strait was the isthmus of land.
Scientists still do not understand how there was colonization of the Americas. Fossil evidence, traditionally used by archaeologists, is not enough to draw any conclusions on the matter, and scientists have to resort to methods that feature more of the work of evolutionary biologists. Genetic study, by researchers at the University of Michigan, allows you to pick one of the theories of people moving to America.
All indigenous peoples of the Americas are descended from one or a few small groups of people, crossing from Chukotka across the Bering Strait.
This happened probably about 12 thousand years ago, when the site of the present Strait existed isthmus.
Alternative version of the colonization of America suggests people in other parts of the world — Asia and Polynesia. This movement of the people could be multiple and occur in several directions as by sea and by land about 30,000 years ago. Polynesians, for example, at the time already were skilled sailors, who were able to settle many islands in the South Pacific Ocean.
These two versions are still more or less equal, and occupied the minds of archaeologists and anthropologists for decades. A large international team of scientists led by Rosenberg November University of Michigan and Andre Ruiz-Linares from University College London, offered a very powerful confirmation of the theory of single migration across the Bering Strait.
An article published by them in PLoS Genetics, at the moment is an example of the most comprehensive analysis of the origins of American nations on the basis of genetic data.
The work of genetics, and anthropologists have studied genetic variation in 678 positions in the DNA of representatives of 29 surviving to date Native American — as in the north part of the world, and in the center and south. For comparison, they chose the DNA of representatives of two peoples of Siberia — Nenets and the Yakut, as well as dozens of other indigenous peoples over the world — from South Africa and Western Europe to northern Mongolia and eastern New Guinea.
By comparing the genetic data, the researchers found a unique set of genetic markers, widespread among the indigenous peoples of the Americas that is not characteristic for any other people, with two exceptions.
The same genetic characteristics recorded only the Nenets and Yakuts.
According to scientists, this set of nucleotides is not responsible for any known biological function of the body and what does not encode any kind of hereditary traits. In their view, this part of the DNA sequence could occur before the actual relocation.
Noah Rosenberg, Professor Center for Computational Medicine and Biology, College of Medicine, University of Michigan notes that such preservation of the DNA fragment in the vast majority of the peoples of the Americas is simply inconceivable, if we assume that the migration to the continent took place in several ways from different geographical areas.
Rather, it means that the migration was once, and if repeated — that in a short time and from the same area of dwelling ancestors of Native Americans.
Moreover, the overall degree of genetic affinity of Indians to the Siberians clearly decreases with distance from the Bering Strait. This also supports the hypothesis of the settling of America through Alaska.
Rosenberg's previous work was to search for and study of the same set of 678 genetic markers in populations of fifty members worldwide. He tried to find the genetic similarities between the nations and compare them with data on the migration of peoples.
The new study also found a reduction in genetic diversity in the transition from the North American nations to the south, and this is the key fact that indicates that the migration was carried out in the recent past.
For the manifestation of mutations that typically occur over a long period of time and bring variety to the original genetic information, just do not have time — that is the opinion of Matthias Jacobson, co-author of Rosenberg.