On Wednesday, scientists reported that they have found evidence of such an extinct branch of our ancestors who separated from us millions of years ago. The evidence of this man was not fossil. Instead, researchers found fragments of their DNA in the genome of living West African people
Arun Durbasul and Sriram Sankararaman, two geneticists at the University of California at Los Angeles, describe the archaeological population of this so-called ghost. Journal of Science Advances. Their invention may shed light on the human genetic diversity of Africa, which is difficult to draw until now, since fossil records are so rare.
The new study is based on a decade of research on ancient DNA derived from human fossils. In 20, a group of researchers released the first genome of a neanderthal. They later found DNA from a fossil in a Siberian cave called Denisova. This genetic material was found to be the second genus of humans called Denisovans, who was closely involved with the Neanderthals.
The ancestors of the Neanderthals and the Denisovans split from our shared ancestors some 600,000 years ago, probably in Africa. They extended to Eurasia, where the Danisovans moved to the east, where the Neanderthals moved west. About 3,000 years ago, both populations went extinct.
As it happened, modern humans evolved in Africa. They later expanded to Eurasia, where they interfered with both the Neanderthals and the Denisovans. Today, All living beings carry some neanderthal DNA. Also, Indigenous Australians as well as people from New Guinea and surrounding areas carry Denisovan DNA.
For the new study, Mr. Durbarusula and Dr. Shankaraman compared a large amount of genetic variation between living humans, Neanderthals and Denisovans.
Researchers tracked how new variants of genes appear in every branch of the human body. In most cases, the data fit with current thinking about human evolution. But in some West African populations, such as Yoruba in Nigeria and Mende in Sierra Leone, some DNA contains variants not found in other living beings or even in Neanderthals or Denisovans.
“What it told us is that this is not a simple story,” said Dr. Sankaraman.
Of the living West Africans, a few percent of the DNA seemed to have been born into a humanoid branch that was not Homo sapiens or other species of our genus known to the gene. The models of Mr. Durvarsula and Dr. Sankararaman suggest that this ghostly archaeological population was separated from that lineage of modern humans, Neanderthals and Denisovans, millions of years ago.
They estimated that about 50,000 years ago the ancestors and ghost archaeological populations of West Africans intervened – curiously, modern Eurasian peoples also intervened with the Neanderthals and the Denisovans.
Scientists could not say which species of ghost archaeological population is. The fossil record of Africa is just a few hints. Millions of years ago there was a species of bus known as Homo erectus in Africa. The oldest fossils of the Homo sapiens are from Morocco 300,000 years ago. However, researchers also found a significant range of other fossils from our genus Africa in that period.
One of the most interesting is the human head just called Io Eleru, a site in Nigeria 11,200 years ago.
The first researchers who eventually studied linked them to West African residents. However, at 20, a group of scientists looked more carefully at the Io Elreu skull and decided that it was an intermediate form between modern humans and Homo erectus.
Mr Durvarsula and Dr Shankaraman have speculated that fossil archaeologists such as Io Eloa may have included demons.
“It’s really possible,” says paleoanthrologist Isabel Krevikowor of Bordeaux University in France. But he cautioned that Africans still need to learn more about the physical and genetic diversity of the species before scientists can come to such a harsh conclusion. “I want a conservative approach,” he said.
The best test of the new study is to find DNA similar to the sections identified by scientists by extracting DNA from fossils such as the IO allele. Scientists have not yet been able to succeed in that effort, as DNA rapidly declines in tropics. But there are scientists Recently, Africa has been able to extract DNA from modern human remains thousands of years ago, so there is hope.
“This is gold standard,” said Dr. Sankararaman. “I can’t wait for it to happen.”