Although Africa has long been considered the cradle of humanity, all of the evidence of ancient genomes have been found in Asia, Europe, and the Americas.
Due to the African climate, which is not suited for DNA preservation, almost no evidence of the human origins was found on the actual continent until now.
In a recent paper published in the journal Science, researchers documented the genetic code of a person that died in nearly 5,000 years ago in Central Africa.
According to scientists, about 60,000 years ago, after the great human migration from Africa, some of the population which have settled in Eurasia migrated back to Africa. They were the first people who practiced and developed agriculture.
Researchers believe that the newly genetically sequenced man found in Africa, who was named Mota, lived in Africa right before the second migration took place. Mota did not have the common Eurasian DNA found in people who have inhabited the region 1,500 after his death.
Thanks to DNA testing of the skull’s inner ear bone, scientists were capable of estimating just how big the second Eurasian migration has been. Inner ear bone sequencing has become the most common technique to get DNA from fossils found in harsh climates.
Andrea Manica, lead author of the research and professor at the University of Cambridge, said that the Eurasian population that returned to Africa was about one-third of the total Eurasian population, which is incredible. However, scientists do not know what determined these populations to return to their home land.
The research team estimated that about 25% of the current East African population accounts to this Eurasian backward migration. Even in other parts of Africa, 5% of the population’s genome is originally from Eurasia.
Manica and her colleagues do not have the slightest clue what could have caused a migration of this scale. Let’s remember that the only evidence they have so far is one skull, so writing history according to this one item would not be wise. However, techniques for DNA sequencing improve and soon scientists will be able to sequence African genome more easily.
As progresses in the genetic field are made, we’ll have more and more evidence and studies trying to write the world’s genetic history.
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