But Mota lacks around 4-7pc of the Ari DNA, which got the scientists wondering, ‘Where did this difference originate?’.
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Archaeologists outside the entrance to the Mota cave in the Ethiopian highlands, where the ancient bones were discovered.
Research spokesperson Doctor Andrea Manica said all of the DNA samples obtained from every location and population in the African continent contained considerable Eurasian genes.
“This is the first ancient human genome found in Africa to have been sequenced”, said Marcos Gallego Llorente, a geneticist at the University of Cambridge and member of the global team of researchers who worked on the project. It’s the latter migration that might need a bit of timeline tweaking.
The researchers traced this injection of genes to an event known as the ‘Eurasian backflow.’ It describes a period a few 3,000 years ago when people from the Near East and Anatolia streamed into the Horn of Africa, a reverse migration to that which led the first humans out of Africa about 100,000 years ago. But as the techniques for extracting and analyzing the ancient DNA of Africa improve, we’ll have more and more studies like this one to fill in the gaps of humanity’s origin story. The cave’s conditions preserved the DNA for millennia, which it doesn’t occur too often.
Africa is a continent that lags behind Asia, Europe and the Americas when it comes to DNA tracing of human fossils, with the hot, humid climate making scientific work all the more hard. The study was published Wednesday in the journal Science.
Scientists concluded that these people were the descendants of a group of ancient farmers that brought agriculture to European regions thousands of years earlier.
Homo sapiens – modern humans – emerged in Africa about 200,000 years ago and migrated off the continent 60,000-to-100,000 years ago, populating nearly every corner of the planet.
Due to the belief that climate played too detrimental a role in DNA preservation, scientists have eschewed Africa and, instead, fled to colder areas like Siberia, where far more of the skeletal remains are salvageable.
According to anthropologist Matthew Curtis from the University of California, Los Angeles and Ventura College, the skeletal remains belonged to an adult male who was bound during his burial, as he was also buried with stone tools inside the grave revealing that Mota also lived during hunter-gatherer times.
But the new study suggests that “mind-blowing” numbers of people must have moved back to account for their presence in the DNA of modern Africans, accounting for around one third of the population. They show that modern African populations, thought to be basically unmixed, actually have significant Eurasian ancestry. He also had genetic adaptations for living at high altitudes – the same adaptations found in Ethiopian highlanders today.
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Given Africa’s role as the evolutionary cradle for humans, genetic diversity in Africa is vital to understanding the evolution of anatomically modern humans.
