When I initially did the post on Cheddar Man, (click here to view) I omitted the issue of what he may have looked like. Facial reconstructions performed In 1998 and 2018 and they were strikingly different. The reason for the dramatic difference? DNA.
Ancient DNA from Cheddar Man, the Mesolithic skeleton discovered in 1903 at Gough's Cave in Cheddar Gorge, Somerset, England was used to build a portrait of Cheddar Man and his life in Mesolithic Britain. He lived around 10,000 years ago and is the oldest almost complete skeleton of our species, Homo sapiens, ever found in Britain.
Coaxing data from ancient DNA is painstaking work. "Ancient DNA doesn't necessarily mean that the specimen you're working with is thousands of years old," Dr. Selina Brace, manager of England's National History Museum ancient DNA labratory, said. "It just means that the DNA is degraded." As soon as an organism dies, DNA begins to break down. Temperature and humidity also make a big difference to the quality of data that it's possible to extract. The consistently cool conditions of Gough's Cave and layers of natural mineral deposits both helped preserve Cheddar Man's DNA.
The Natural History Museum researchers extracted the DNA from part of the skull near the ear known as the petrous. At first, they were not sure if they'd get any DNA at all from the remains. "To extract ancient DNA from a human or animal what you're looking for is a dense bone which might have protected the DNA inside it as much as possible," Dr. Brace said. "We used to use leg bones or teeth as the thick bones and enamel keep DNA quite intact, but in the last two years we've shifted to using the petrous, or inner ear bone, which is the densest bone in the human body. However...you can still fail to retrieve useful DNA. But if the body was deposited in a good environment, where there was a cool and constant temperature then the petrous bone is a good place to find useful ancient DNA."
They were in luck. Not only was DNA preserved, but Cheddar Man yielded the highest coverage (a measure of the sequencing accuracy) for a genome from that period of European prehistory, known as the Mesolithic or Middle Stone Age.
After extracting the DNA, Dr. Brace and the team used next-generation shotgun sequencing, which involves defining millions of fragments of DNA distributed randomly across the genome, to create a library of Cheddar Man's DNA and map what they found against a modern human genome. They then teamed up with researchers at University College London (UCL) to analyze the results, including gene variants associated with hair, eye and skin color.
Researchers now say he was part of a group of hunter-gatherer immigrants from continental Europe who’d settled in Britain shortly after the last ice age. Today’s white Britons are descendants of that immigrant population, one that, until recently, had been assumed to be fair-skinned. But, by sequencing Cheddar Man’s entire genome and reconstructing his face using cutting-edge techniques, scientists at the Natural History Museum and University College London proved the assumption wrong.
The model of Cheddar Man was made by a company that specializes in life-like reconstructions of extinct mammals and early humans. The artists took measurements of the skeleton, scanned the skull and 3D printed a base for their model. Facial reconstructions are part art and part science. The result? Cheddar Man had blue eyes, dark colored curly hair and 'dark to black ' skin pigmentation. Close genetic matches to Cheddar Man have been found in remains in western Europe at sites including Spain, Hungary and Luxembourg.
Scientists say that Cheddar Man’s ancestors arrived in the Britain via the Middle East, after coming out of Africa.
Dr. Rick Schulting, an archaeology professor at Oxford University said: "It may be that we may have to rethink some of our notions of what it is to be British, what we expect a Briton to look like at this time." A previous reconstruction of Cheddar Man, made by the University of Manchester before DNA tests were available, depicted him with white skin, brown eyes, not blue, as well as straighter and lighter hair
Cheddar Man "is just one person, but also indicative of the population of Europe at the time," said Dr. Tom Booth, a researcher at the Natural History Museum. "They had dark skin and most of them had pale colored eyes, either blue or green, and dark brown hair. Cheddar Man subverts people's expectations of what kinds of genetic traits go together. It seems that pale eyes entered Europe long before pale skin or blond hair, which didn't come along until after the arrival of farming. He reminds us that you can't make assumptions about what people looked like in the past based on what people look like in the present, and that the pairings of features we are used to seeing today aren't something that's fixed."
Geneticist Susan Walsh at Indiana University–Purdue University Indianapolis, said that we simply do not know his skin color. Dr. Walsh believes that the tests cannot prove Cheddar Man's skin color and that his DNA may have degraded over the past 10,000 years. Speaking to New Scientist, she said: 'It’s not a simple statement of "this person was dark-skinned. It is his most probable profile, based on current research." DNA testing is not advanced enough to say for certain.
The new discovery suggests that light skin evolved in European populations much later than is commonly believed. "People define themselves by which country they’re from, and they assume that their ancestors were just like them," said Alfons Kennis, who worked on the reconstruction. "And then suddenly new research shows that we used to be a totally different people with a different genetic makeup."
Common European traits like pale skin evolved relatively recently in central and southern Europe. Researchers had long assumed that skin lightened as humans migrated from Africa and the Middle East into Europe around 40,000 years ago. Experts had speculated that shorter day lengths and a sun lower in the sky favored lighter skin, which more easily synthesized vitamin D. But a groundbreaking 2015 analysis of the genomes of 83 prehistoric Europeans showed that populations in Europe about 8,000 years ago were still mixed and diverse.
Traits commonly associated with modern Europeans, such as tallness, the ability to digest milk, and lighter skin tone, only became ubiquitous in Europe relatively recently. Experts found that about 8,500 years ago, early hunter-gatherers in central and southern Europe, including Spain, Luxembourg, and Hungary, had darker skin. They lacked versions of two genes which were responsible for "depigmentation" and, hence, pale skin in Europeans today. In the far north of Europe, where low light levels favored pale skin, the team found hunter-gatherers had a lighter complexion.
The new DNA information has proven to be quite revolutionary. It has revealed more information than we knew before. Cheddar Man is thought to have had a relatively good diet and his bones suggest that he would be much stronger than most people today.
Although previous populations had settled in Britain long before his arrival, they were wiped out before him and he marked the start of continuous habitation on the island.
Cheddar Gorge was populated by cannibals 14,700 years ago, who decapitated their dead, filleted the flesh from their bodies and made cups from their skulls. The DNA profile of Cheddar Man has revealed that he shares no direct ancestry with these earlier cannibals.
As stated, we know for certain that he had the gene for blue eyes. We also know for certain that he did not have the modern alleles (pairs or series of genes on a chromosome that determine the hereditary characteristics, such as the gene that determines hair color) that produce white skin in European and western Eurasian populations today. Put together, there is a strong likelihood that he was at least tanned in look and did not have pale skin.
The contention is with the actual shade of his skin. The shade they ultimately chose to represent him with was arrived at with a probabilistic calculation based on comparisons of modern day genomes. Obviously there are a few issues with this. Different alleles influence skin color in different populations around the world. Other parts of Cheddar Man's genome could have influenced his skin color, but insofar as our understanding of skin color genetics is incomplete, we can only have limited confidence in reconstructing his actual shade of skin color.
Per Dr. Tom Booth: "It really shows us that these imaginary racial categories that we have are really very modern constructions, or very recent constructions, that really are not applicable to the past at all."
Our ancestors come in all different shapes and sizes, with a variety of eye color, hair color and pigmentation. We also all have 9,000 year old ancestors. I just happen to know who one of them was and, now, what he allegedly may have looked like.
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