Neanderthal DNA found in African people for the first time
Scientists have found, for the first time, conclusive evidence that the DNA of Neanderthals exists in modern Africans.
A new study by Princeton University reveals that African people, who were previously thought to have no Neanderthal DNA, obtained about 0.3 percent of their genes from our extinct ancestors.
The Africans obtained a sliver of Neanderthal DNA after breeding with humans who migrated to Africa from Europe.
The ancestors of these people were raised with Neanderthals, providing an indirect pathway for the DNA of Neanderthals in Africans.
This breakthrough means that scientists have discovered that Native Europeans, Asians, Africans and Americans have Neanderthal DNA.
It also reveals that non-African populations have a larger and more balanced distribution of Neanderthal DNA than previously assumed.
The researchers observed levels of Neanderthal ancestry in Europeans (51 Mb / individual), East Asians (55 Mb / individual) and South Asians (55 Mb / individual) that were strikingly similar to each other.
Scroll down to watch the video
One study finds that previous assumptions that Africans were not raised directly with Neanderthals are true, but without realizing they received Neanderthal DNA from those who originated in parts of the world whose ancestors had mated with Neanderthals (in the image, the two stages that led to Neanderthal DNA are found in Africans)
Neanderthals disappeared about 40,000 years ago, but their DNA is still alive in modern humans thanks to the cross between the two species (archive photo)
Dr. Aaron Wolf, author of the University of Washington study, told MailOnline: “ We believe that a large part of Neanderthal ancestry in African populations is due to the historical migratory migration of an ancestral European population to Africa.
‘That is, ~ 100,000 years ago there was a great wave of migration outside Africa, from which the vast majority of modern non-African populations descend.
‘Parts of this population crossed with Neanderthals (~ 50,000 years ago) and transmitted the DNA of Neanderthals to today’s human populations.
‘We believe that part of this non-African population of Neanderthals returned to Africa and introduced Neanderthal DNA into African populations.
“It is important to note that we believe this happened after the division of the populations of Europe and East Asia (approximately 30,000 years ago).”
He also revealed that some of the DNA of Neanderthals in Africans today is actually due to human DNA placed in the Neanderthal genome.
This is the result of the cross between Neanderthals and humans that dispersed outside Africa about 200,000 years ago, before the main migration occurred.
“This population has not contributed significantly to the genetics of modern non-African populations, but it can still be detected from its DNA in the Neanderthal genome,” Wolf told MailOnline.
The scientists identified regions of Neanderthal ancestry in Africans for the first time by identifying, on average, 17 megabases (Mb) of Neanderthal DNA per individual.
This corresponds to approximately 0.3 percent of the genome of African peoples from Neanderthals, which became extinct about 40,000 years ago.
East Asians, who were thought to have 20 percent more Neanderthal DNA than Europeans, actually only have 8 percent more, scientists discovered.
“This suggests that most of the Neanderthal ancestry that individuals have today goes back to a common hybridization event that involves the ancestral population of all non-Africans, which occurs shortly after dispersion outside Africa,” said Dr. Joshua Akey of Princeton University. and says the author of the study.
Previously it was thought that Neanderthals crossed paths with Homo sapiens after people first emigrated from the continent.
But this study reveals that ancient Europeans probably returned to Africa and grew up with Africans, introducing Neanderthals’ DNA into their genome.
Find previous assumptions that Africans were not raised with Neanderthals directly are true, but without realizing they received DNA from Neanderthals from those who originated in parts of the world whose ancestors had mated with Neanderthals.
“I am surprised at the fact that we often conceptualize human history in very simple terms,” says Dr. Akey.
‘For example, we often imagine that there was only one dispersion outside Africa that happened 60,000 to 80,000 years ago that led to the world’s population.
“However, our results show that this story was much more interesting and there were many waves of dispersion outside Africa, some of which led to a mixture between modern humans and Neanderthals that we see in the genomes of all living individuals today.” .
WHO WAS THE NEANDERTHALS?
The Neanderthals were a close human ancestor who mysteriously disappeared about 50,000 years ago.
The species lived in Africa with the first humans for hundreds of millennia before moving to Europe about 500,000 years ago.
Later, they joined humans who made the same trip sometime in the last 100,000 years.
The Neanderthals were a kind of human cousins, but not a direct ancestor, the two species separated from a common ancestor, which perished about 50,000 years ago. The photo is an exhibition of the Neanderthal Museum
These were the original ‘cavemen’, which historically were thought to be silly and brutal compared to modern humans.
However, in recent years, and especially in the last decade, it has become increasingly evident that we have been selling Neanderthals in short.
A growing body of evidence points to a more sophisticated and talented type of ‘caveman’ than anyone thought possible.
Now it seems likely that Neanderthals buried their dead with the concept of a future life in mind.
In addition, their diets and behavior were surprisingly flexible.
They used body art as pigments and beads, and they were the first artists, with Neanderthal rock art (and symbolism) in Spain apparently prior to the oldest modern human art for about 20,000 years.
The Africans, who were previously believed to have no Neanderthal DNA, obtained 0.3% of their genes from our ancient ancestors. This breakthrough means that scientists have discovered that Native Europeans, Asians, Africans and Americans have Neanderthal DNA.
In a study published in the magazine. CellThe Princeton University researchers used a computational method, called IBDmix, to evaluate the DNA of 2,504 modern Africans and non-Africans.
The method looks for sections of DNA in two individuals that is identical, which implies that they once shared a common ancestor.
Co-first author Lu Chen, a postdoctoral research associate at the Lewis-Sigler Institute of Integrative Genomics (LSI) in Princeton, said: ‘This is the first time we can detect the real sign of Neanderthal ancestry in Africans.
“And surprisingly it showed a higher level than we previously thought.”
Then, the scientists used the principle of IBD, identity by descent, to identify the DNA of Neanderthals in the human genome.
The new method uses characteristics of the Neanderthal sequence to distinguish shared ancestry from recent cross-linking.
The researchers were able to identify Neanderthal ancestors in Africans for the first time and estimated that Europeans and Asians had Neanderthal ancestry levels more equal than previously thought.
He adds that part of the Neanderthal ancestry detected in Africans was actually due to the human DNA introduced into the Neanderthal genome.
While the researchers acknowledged the limited number of African populations they analyzed, they hope their new method and findings will encourage further study of Neanderthal ancestry in Africa and other populations.
WHAT DO WE KNOW ABOUT HUMANKIND’S JOURNEY OUT OF AFRICA?
The traditional ‘Outside Africa’ model suggests that modern humans evolved in Africa and then left in a single wave about 60,000 years ago.
The model is often held once modern humans left the continent, there was a brief period of crossing with Neanderthals.
This explains why today’s European and Asian heritage individuals still have ancient human DNA.
There are many theories about what prompted the fall of the Neanderthals.
Experts have suggested that early humans may have carried tropical diseases with them from Africa that annihilated their ape-like cousins.
Others claim that the fall in temperatures due to climate change ended with Neanderthals.
The prevailing theory is that the first humans killed the Neanderthal through competition for food and habitat.
How history is changing in light of new research
Recent findings suggest that the ‘Out of Africa’ theory does not tell the full story of our ancestors.
Instead, multiple and smaller movements of humans outside Africa that began 120,000 years ago were followed by a major migration 60,000 years ago.
Most of our DNA is made up of the latter group, but previous migrations, also known as ‘dispersions’, are still evident.
This explains recent studies of the first human remains that have been found in the confines of Asia for more than 60,000 years.
For example, remains of H. sapiens have been found in multiple sites in southern and central China dating back between 70,000 and 120,000 years ago.
Other recent findings show that modern humans arrived in Southeast Asia and Australia before 60,000 years ago.
According to these studies, humans could not have come in a single wave of Africa around this time, according to studies.
Instead, the origin of man suggests that modern humans developed in multiple regions of the world.
The theory states that groups of prehuman ancestors left Africa and spread throughout parts of Europe and the Middle East.
From here, the species became modern humans in several places at once.
The argument is for a new analysis of a 260,000-year-old skull found in Dali County in the Chinese province of Shaanxi.
The skull suggests that the first humans emigrated to Asia, where they developed modern human traits and then returned to Africa.