Most of us have some Neanderthal genes in our DNA.
Scientists have discovered that most people have a little bit of Neanderthal man in them. A major DNA study suggests that our ancestors interbred with the Neanderthals at least twice tens of thousands of years ago – and that their genes have been carried down the millennia ever since.
The discovery adds to the mystery surrounding the Neanderthals, an offshoot of the human family tree who vanished in Europe around 25,000 years ago.
Some researchers have argued that the Neanderthals were driven to extinction by modern humans. But others say the two species merged.
The new findings come from a genetic analysis of nearly 2,000 people from around the world.
Dr Jeffrey Long, a genetic anthropologist at the University of New Mexico, who carried out the study, said: ‘It means Neanderthals didn’t completely disappear.’
He added: ‘There is a little bit of Neanderthal left over in almost all humans.’
Many scientists believe that modern humans evolved in Africa between 200,000 and 100,000 years ago. Our ancestors left Africa around 60,000 years ago and migrated around the world – replacing other branches of the family tree which had left Africa earlier – including the Neanderthals.
By 25,000 years ago the Neanderthals had vanished from Europe.
Some experts believe they interbred with modern humans, others that they were driven to extinction by changing climate or competition for food.
The latest study looked at DNA from 1,983 people living in Africa, European, Asia and the Americas.
Scientists, led by Dr Sarah Joyce at the University of Mexico, then created an “evolutionary tree” to explain how and when differences in the DNA between people from around the world appeared.
She found that the best explanation was if there were two periods of interbreeding between modern humans and another human species – and that Neanderthals were the only likely candidate.
One period of interbreeding occurred around 60,000 years ago in the eastern Mediterranean, the other around 45,000 years ago in eastern Asia.
The two events happened after our ancestors migrated out of Africa to colonise the rest of the world. The researchers found evidence of interbreeding between Neanderthals and modern Africans – supporting the theory.
The findings were presented at the American Association of Physical Anthropologists conference in New Mexico and have triggered huge excitement among experts in human evolution.
Dr Noah Rosenberg, an anthropological geneticist at the University of Michigan in Ann Arbor, told the journal Nature: ‘They are onto something.’
The findings support scientists who believe there is evidence of interbreeding in fossils.
Neanderthals had thick set features and heavy foreheads. They were around six inches shorter on average than modern people, but their brains were 20 per cent bigger.
In recent years, scientists have found evidence that they were more sophisticated than their popular image, and may have developed language.
They used flint and stone tools, and were excellent hunters. They supplemented their diet of deer, bison, boar and bear with seal, fish, shellfish, nuts, grains and plants.
It may not take long for the new theory to be proved.
Other researchers from the Max Planck Institute, led by Svante Pääbo, completed the first draft of the complete Neanderthal DNA last year.
The results are expected to be published soon and may shed more light on breeding between the two species.
Via Daily Mail