Categories: world

The new face of South American people – ScienceDaily

The history of the American population has just been re-interpreted. The largest and most comprehensive survey ever conducted on the…

The history of the American population has just been re-interpreted. The largest and most comprehensive survey ever conducted on the basis of fossil DNA extracted from ancient human remains found on the continent has confirmed the existence of a single ancestral population for all American ethnic groups, past and present.

17,000 years ago The original quota went over the Bering stretch from Siberia to Alaska and began to collide the New World. Fossil DNA shows an affinity between this migration stream and the populations of Siberia and northern China. Contrary to traditional theory, it had no link to Africa or Australasia.

The new study also reveals that once they had settled in North America, the descendants of this past flow were killed in two lines about 1

6,000 years ago.

members of a line stretched over Isthmus in Panama and populated South America into three different consecutive waves.

The first wave occurred between 15,000 and 11,000 years ago. The other took place no more than 9000 years ago. There are fossil DNA records from both migrations throughout South America. The third wave is much later, but its influence is limited when it occurred 4,200 years ago. The members settled in central Andes.

An article about the study has just been published in the journal Cell a group of 72 researchers from eight countries, affiliated to São Paulo University in the United States. Brazil, Harvard University in the United States and Max Planck Institute for Human History Science in Germany, among others.

According to the scientists’ findings, the line that made the north-south route between 16,000 and 15,000 years ago belonged to the Clovis culture, named after a group of archaeological sites excavated in the western US and from 13 500-11 000 years ago.

The Clovis culture was named when flint spikes were found in the 1930s at a digging in Clovis, New Mexico. Clovis sites have been identified throughout the United States and in Mexico and Central America. In North America, the Clovis people Pleistocene chased megafaunas as giant sluts and mammoths. With the decline of megafauna and its eradication 11,000 years ago, the Clovis culture finally disappeared. Long before, bands of hunter-collectors had traveled south to explore new hunting fields. They ended up living in Central America, as evidenced by 9,400-year human fossil DNA found in Belize and analyzed in the new study.

At a later time, perhaps while driving mastodon herds, Clovis hunter gathered over Isthmus in Panama and spread to South America, as evidenced by genetic data from burial places in Brazil and Chile revealed now. This genetic evidence confirms well-known archaeological finds such as the Monte Verde site in southern Chile, where people slaughtered mastodons 14,800 years ago.

Among the many famous Clovis sites is the only burial site associated with Clovis tools in Montana, where the remains of a boy (Anzick-1) were found and dated 12 600 years ago. DNA extracted from these bones has links to DNA from skeletons of people living between 10,000 and 9,000 years ago in caves near Lagoa Santa, Minas Gerais State, Brazil. In other words, the Lagoa Santa people were partial descendants of Clovis immigrants from North America.

“From the genetic point of view, the Lagoa Santa people are descendants of the first Americans,” said archeologist André Menezes Strauss, who coordinated the Brazilian part of the study. Strauss is connected to the University of Sao Paulo’s Museum of Archeology and Ethnology (MAE-USP).

“Surprisingly, the members of this first relatives of South Americans left no identifiable descendants among today’s Americans,” he said. “Some 9000 years ago, their DNA completely disappears from the fossil samples and replaced by DNA from the first wave of pre-Clovis culture. All living Amerindians are the descendants of this first wave. We do not yet know why the genetic stock of the Lagoa Santa people disappeared . “

A possible cause of the DNA disappearance from the second migration is that it is diluted into the DNA of the Americans that are subsequent to the first wave and can not be identified by existing methods of genetic analysis.

According to Tábita Hünemeier, a Genetics at the University of Sao Paulo Bioscience Institute (IB-USP), who participated in the research, “was one of the most important findings of the study identification of Luzias people genetically related to the Clovis culture, which discontinues the idea about two biological components and the possibility that there were two migrations to America, one with African characteristics and the other with Asian features. “[19659003]” Luzias people must have been the result of a migratory wave originating in Beringia, “she said, referring to the now immersed Bering landing bridge that joined Siberia to Alaska during the iceberg when the sea level was lower.

“Molecular data suggests population substitution in South America since 9000 years ago. Luzias people disappeared and replaced by the American individuals today, although both had a common origin in Beringia, said Hünemeier.

Brazilian Contribution ]

The contribution of Brazilian researchers to the study was fundamental. Among the 49 individuals from which fossil DNA was taken, seven skeletons were dated between 10 100 and 9 100 years ago from Lapa do Santo, a mountain guard in Lagoa Santa.

The seven skeletons, along with dozens of others, were found and rescued in subsequent archaeological campaigns on the site, initiated by Walter Alves Neves, a physical anthropologist at IB-USP and since 2011 by Strauss. The archaeological campaigns led by Neves between 2002 and 2008 were funded by the São Paulo Research Foundation – FAPESP.

In summary, the new study examined fossil DNA from 49 people on 15 archaeologists places in Argentina (two places, 11 people dating between 8 900 and 6 600 years ago), Beliz e (one place, three people dated between 9 400 and 7 300 years ago), Brazil (four places, 15 people dated between 10 100 and 1000 years ago), Chile (three places, five individuals dating between 11,100 and 540 years ago) and Peru (seven places, 15 people dating between 10,100 and 730 years ago).

The Brazilian skeletons come from the archaeological sites of Lapa do Santo (seven individuals dating back 9,600 years ago), Jabuticabeira II in Santa Catarina State, a sambaqui or scallop with five individuals dating about 2,000 years ago, and from two Coin in the Ribeira Valley, São Paulo State: Laranjal (two individuals dating about 6,700 years ago) and Moraes (an individual dated about 5 800 years ago).

Paulo Antônio Dantas de Blasis, an archaeologist associated with the MAE-USP, led the excavation of Jabuticabeira II, also supported by FAPESP through a thematic project.

The graves at the river middle places in São Paulo State were led by Levy Figuti, also an archaeologist at MAE-USP, and also supported by FAPESP.

“The Moraes skeleton (5,800 years old) and the Laranjal skeleton (6 700 years old) are among the oldest from the south and southeast of Brazil,” said Figuti. “These sites are strategically unique because they are located between the Atlantic and the Atlantic, and make a significant contribution to our understanding of how Southeast Asia in Brazil was.”

These skeletons were found between 2000 and 2005. From the beginning, they presented a complex blend of coastal and inland cultural characteristics, and the results of their analysis generally varied, except in the case of a skeleton diagnosed as Paleoindian (analysis of its DNA is not yet complete).

“The study just published represents a major step forward in archeological research, which exponentially increases what we knew just a few years ago about the archeogenetics of the American population,” says Figuti.

Hünemeier has also recently made an important contribution to the reconstruction of human history in South America using paleogenomics.

Amerindian Genetics

Not all human resources d at some of the oldest archaeological sites in Central and South America belonged to genetic descendants of Clovis culture. The residents in several places did not have Clovis-associated DNA.

“This shows that in addition to the genetic contribution, the second migration wave to South America, which was Clovis-associated, could also have brought about technical principles that would be expressed in the famous fishtail points found in many parts of South America,” Strauss said. 19659003] How many human migrations from Asia came to America at the end of the Ice Age more than 16,000 years ago, so far, was unknown. The traditional theory, formulated in the 1980s by Neves and other researchers, was that the first wave had African characteristics or characteristics similar to the Australian aboriginals.

The well-known forensic reconstruction of Luzia was performed in accordance with this theory. Luzia is the name of the fossil shell of a woman who lived in the Lagoa Santa region 12 500 years ago and is sometimes called “the first Brazilian “.

Luzias bust with African characteristics was built on the basis of Skull’s morphology of British anatomy will be the artist Richard Neave in the 1990s.

“The skull form, however, is not a reliable marker of anonymity or geographical origin. Genetics is the best foundation for this kind of inference,” Strauss explained. [19659003] “The genetic results of the new study show categorically that there was no significant relationship between the Lagoa Santa people and groups from Africa or Australia. So the hypothesis that Luzi’s people derive from a migration wave before the ancestors of today’s Amerindians have been contradicted. On the contrary, the DNA shows that Luzias people were completely American. “

A new bust has replaced Luzia in the Brazilian scientific pantheon. Caroline Wilkinson, a forensic anthropologist at Liverpool John Moores University in Great Britain and a disciple of Neave, has produced a facial reconstruction of one of the individuals raised at Lapa do Santo. The reconstruction was based on a retro-shaped digital model of the skull.

“As we are at the traditional facial building of Luzia with strong African characteristics, this new facial reconstruction reflects the physiognomy of the first inhabitants of Brazil much more accurately, demonstrating the generalized and countless features that the great American diversity was established for thousands of years” said Strauss.

The study published in Cell he added, also presents the first genetic data on the Brazilian coastal Sambaquis.

“These monumental shells were built 2,000 years ago by the peoples’ communities living on the coast of Brazil. Analysis of fossil DNA from shell cuttings in Santa Catarina and São Paulo shows that these groups were genetically related to the Americans living today in southern Brazil, in particular Kaingang Groups, “he said.

According to Strauss, DNA extraction from fossils is tec hnically very challenging, especially if the material was found in a place with a tropical climate. For nearly two decades, extreme fragmentation and significant contamination prevented various research groups from successfully extracting genetic material from the bones found at Lagoa Santa.

This has now been done thanks to methodological advances developed by Max Planck Institute. As Strauss enthusiastically explained, much remains to be discovered.

“Construction of Brazil’s first archeogenetic laboratory is scheduled to begin in 2019 thanks to a partnership between the São Paulo University Museum of Archeology and Ethnology (MAE) and its Bioscience Institute (IB), funded by FAPESP. give a new challenge to research about South America and Brazil, “said Strauss.

“To a certain extent, not only what we know about how the region was popular but also changing significantly how we study human skeleton remains,” changes Figuti.

Human remains were first found in Lagoa Santa 1844, when Danish natural scientist Peter Wilhelm Lund (1801-1880) discovered 30 skeletons deep in a flooded cave. Almost all of these fossils now exist at Denmark’s Natural History Museum in Copenhagen. A single skull has stayed in Brazil. It was donated by Lund to the Brazilian History and Geography Institute in Rio de Janeiro.

Colonization with Leap

The same day as the Cell article was published (November 8, 2018), a magazine in the journal Science also reported new findings about fossil DNA from the first migrants to America. André Strauss is one of the authors.

Among the 15 ancient skeletons from which genetic material was taken belong five to the Lund Collection in Copenhagen. They run from 10 400 to 9 800 years ago. They are the oldest in the test, along with an individual from Nevada estimated at 10 700 years old.

The sample consisted of fossil human residues from Alaska, Canada, Brazil, Chile and Argentina. The results of its molecular analysis suggested that the people of America of the first human groups from Alaska did not come only through gradual occupation of territory while growing population.

According to the researchers responsible for the study, suggesting that the first people invade Alaska or neighboring Yukon, are divided into two groups. This occurred between 17 500 and 14 600 years ago. One group colonized North and Central America, the other South America.

The American population followed as small tribes of hunter-gatherers traveled to settle in new areas until they came to Tierra del Fuego in a movement lasting one or more two millennia.

Among the 15 people whose DNA was analyzed, three of Lagoa Santa’s five showed some genetic material from Australasia, as suggested by Neves theory of occupation of South America. The researchers can not explain the origins of this Australasian DNA or how it ended up in just some of the Lagoa Santa people.

“That the genomic signature in Australasia has been present for 10,400 years in Brazil but is absent in all the tests so far, which are as old or older, and found further north, is a challenge in view of its presence in Lagoa Santa , “they said.

Other fossils gathered during the twentieth century include the Luzia skull, found in the 1970s. Almost 100 skulls excavated by Neves and Strauss for the past 15 years are now held at the USP. A similar number of fossils are held at the Pontifical Catholic University of Minas Gerais (PUC-MG).

However, the vast majority of these osteological and archaeological treasures belonging to more than 100 individuals were deposited at the National Museum of Rio de Janeiro and probably destroyed in the fire ravaged by this historic building on September 2, 2018.

Luzia Scale was shown at the National Museum together with Neave’s face reconstruction. Researchers feared it had been lost to the fire but fortunately it was one of the first items that would be recycled from the ruins. It had broken but survived. The fire destroyed the original facial reconstruction (of which there are several copies).

Share
Published by
Faela