Reconstruction of Cheddar Man, so named for his discovery in Somerset's Cheddar Gorge in 1903
Groundbreaking DNA research has shone new light on the early origins of Britain's early settlers, reconstructing in unprecedented detail the face of Cheddar Man, the nation's oldest near-complete skeleton. The research reveals he had much darker features than was previously assumed, which has implications for our understanding of how lighter pigmentation spread through Europe.
Previous reconstructions of Cheddar Man, so named for his discovery in Somerset's Cheddar Gorge in 1903, weren't based on DNA data and painted a Mesolithic man with a lighter skin tone. He lived around 10,000 years ago, after his hunting and gathering ancestors migrated to Europe at the end of the last Ice Age, a time when Britain was attached to continental Europe.
"Until recently it was always assumed that humans quickly adapted to have paler skin after entering Europe about 45,000 years ago," says Dr Tom Booth from Britain's Natural History Museum. "Pale skin is better at absorbing UV light and helps humans avoid vitamin D deficiency in climates with less sunlight."
But using newly available DNA analysis, scientists from University College London (UCL) and the Natural History Museum have found that Cheddar Man actually has genetic markers usually associated with sub-Saharan Africa. The team drilled a 2 mm hole into his skull to gather bone powder from the petrous bone, the densest bone in the human body and therefore especially good at safeguarding the ancient DNA.
The process that followed made Cheddar Man the oldest British individual to have their genome sequenced. That information was then passed on to reconstruction specialists, who measured up the skeleton, scanned the skull and 3D printed a base for the model.
"Of course facial reconstruction is part art and part science," says Booth. "But there are some standards of how thick the tissue is in different regions of people's faces so they can use those conventions to develop the morphology of the face."
The blue eyes, dark curly hair and darker skin pigmentation of Cheddar Man suggests that the lighter pigmentation associated with Northern Europe came to be far more recently than previously thought. The portrait painted by the scientists is similar to that of several other Mesolithic skeletons to have their DNA analyzed around Europe.
"Cheddar Man's genetic profile places him with several other Mesolithic-era Europeans from Spain, Hungary and Luxembourg whose DNA has already been analyzed," UCL's Professor Thomas explains. "These 'Western Hunter-Gatherer's' migrated into Europe at the end of the last Ice Age and the group included Cheddar Man's ancestors."
The researchers say that today, around 10 percent of British indigenous ancestry can be linked to that population.
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