Richard Burton and the Cheddar Man

The Cheddar Man of Somerset
Richard Burton of Wales

Cheddar Man is a human male fossil found in Gough’s Cave in Cheddar Gorge, Somerset, England. The skeletal remains date to the Mesolithic (ca. 9100 BP, 7100 BC) and it appears that he died a violent death. A large crater-like lesion just above the skull’s right orbit suggests that the man may have also been suffering from a bone infection. Excavated in 1903, Cheddar Man is Britain’s oldest complete human skeleton. The remains are kept by London’s Natural History Museum, in the Human Evolution gallery. Analysis of his nuclear DNA indicates that he was a typical member of the western European population at the time, with lactose intolerance, probably with light-coloured eyes (most likely green but could be blue or hazel), dark brown or black hair, and dark to black skin. Nuclear DNA was extracted from the petrous part of the temporal bone by a team from the Natural History Museum in 2018. The genetic markers suggested (based on their associations in modern populations whose phenotypes are known) that he probably[4] had green eyes, lactose intolerance, dark curly or wavy hair, and dark/brown-to-black skin.[2][5] These features are typical of the Western European population of the time, now known as West European Hunter-Gatherers. This population forms about 10%, on average, of the ancestry of Britons without a recent family history of immigration.

Brown eyes, lactose tolerance, and light skin are common in the modern population of the area. These genes came from later immigration, most of it ultimately from two major waves, the first of Neolithic farmers from the Near East, another of Bronze Age pastoralists, most likely speakers of Indo-European languages, from the Pontic steppe.[2][6]

Cheddar Man’s Y-DNA belonged to an ancient sister branch to modern I2-L38 (I2a2). The I2a2 subclade is still extant in males of the modern British Isles and across other parts of Europe. The mitochondrial DNA of Cheddar Man was discovered to be haplogroup U5b1 by a Natural History Museum study in 2018 using next generation sequencing. Some 65% of western European Mesolithic hunter-gatherers had haplogroup U5; today it is widely distributed, at lower frequencies, across western Eurasia and northern Africa. In 1996, Bryan Sykes of the University of Oxford first sequenced the mitochondrial DNA from one of Cheddar Man’s molars as U5a using PCR testing. The difference between the older result and the 2018 Natural History Museum result was attributed to the use of older PCR technology and possible contamination. (Wikipedia)

National Geographic, by Sarah Gibbens (Published February 7, 2018)

A recent facial reconstruction of a 10,000-year-old skeleton called the ”Cheddar Man” has revealed a man with bright blue eyes, slightly curly hair, and dark skin. ”It might surprise the public, but not ancient DNA geneticists,” says Mark Thomas, a scientist at the University College London. That’s because a new analysis of the ancient man’s DNA proves he’s genetically similar to other dark-skinned individuals from the Mesolithic era found in Spain, Hungary, and Luxemborg whose DNA has already been sequenced. The new revelation places the Cheddar Man among a group of hunter-gatherers that are thought to have migrated to Europe at the end of the last Ice Age some 11,000 years ago. They started the reconstruction by taking measurements of the skull. ”He had a thick, heavy cranium and a relatively light jaw,” says Thomas. Researchers then sequenced the Cheddar Man’s entire genome. He’s the oldest British individual whose genes scientists have mapped. From the sequence, they learned skin color, eye color, and hair type. Finally, to bring the Cheddar Man to life, experienced Dutch model makers Adrie and Alfons Kennis used 3D scans and printing to add the ”flesh” to his reconstructed bones.

The genes that determine skin color are mapped across various chromosomes, says Miguel Vilar, the science manager for National Geographic’s genome project. Vilar was not involved in the reconstruction but says scientists would have had to look at billions of data points, something we have previously been unable to do with ancient DNA …

How and when Britons developed lighter skin over time is unclear. ”We think it’s because light skin allows for more UV radiation, which helps break down vitamin D,” says Vilar. In more temperate regions, where ancient humans were less exposed to sunlight, they would have needed to absorb more radiation to break down the essential vitamin needed for healthy bones. ”In my view, that’s the most robust theory for skin pigmentation,” says Thomas. ”But it doesn’t explain eye pigmentation. There are other processes that go on. It could be sexual selection. It could even be something else we don’t yet understand.” Another theory put forth in a 2014 study suggested that as humans began cultivating farms, their diets became less diverse and thus they would have needed to absorb more vitamin D from the sun…” (excerpts)

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