By Meredith Bennett
A recent advancement in the study of an ancient human skeleton named ‘Cheddar Man’ has stunned people everywhere by giving them a better understanding of what the earliest Britain inhabitants looked like. Cheddar man is a ten-thousand-year-old skeleton that was discovered in Cheddar Gorge in Somerset, England. It is believed that he migrated to Europe around eleven thousand years ago, near the end of the last ice age, and was part of a group of hunter-gatherers related to similar groups that were living in Spain, Hungary, and Luxembourg during the Mesolithic Era.
Mark Thomas, a scientist at University College London worked with the Natural History Museum in London to reconstruct Cheddar Man’s face. First, they measured Cheddar Man’s skull and found that he had a thick, substantial cranium and light jaw. They then sequenced his entire genome, becoming the oldest Briton to have his genes mapped. His genes revealed that Cheddar Man had dark skin, blue eyes, and wavy hair. Then, using 3D scans, Adrie and Alfons Kennis, professional Dutch model makers, made a model of Cheddar Man’s face.
The genes that determine our skin color are spread over several chromosomes. There are many variants, or alleles, for skin pigmentation which can be seen in the large spectrum of skin color among humans around the world. Dissimilarly, eye color is determined by one specific gene, and has one specific variant in that gene. Why is this? Scientists are still not sure. It is also unknown for sure why humans developed lighter skin at all. The most widely accepted hypothesis is that different skin pigmentations are more beneficial depending on where you live. All humans are descended from the first Homo sapiens population that evolved in Africa. Once people migrated out of Africa, however, conditions were different. People living in temperate areas, like Britain, received less sunlight, and lighter skin is known to allow more UV radiation into the body. UV radiation breaks down vitamin D which is essential to the development of healthy bones. his means that having lighter skin was more beneficial than dark skin for people living in areas where sunlight was not as readily available. The discovery of Cheddar Man’s dark skin implies that skin pigmentation in Western Europe evolved relatively recently in terms of human history.
There are still many questions to answer. Why does eye pigmentation tend to coevolve with skin color? How did the dietary, migratory, and cultural changes of early humans lead to the diversity we see today? Scientists also want to know more about the effects of exposure to pathogens on populations since ten thousand years ago, when Cheddar Man was living. Did people of European descent develop disease immunities that resulted from the Bubonic Plague? Discoveries like Cheddar Man and questions like these will lead us into the next stage of human evolutionary studies.
To see a picture of the model of Cheddar Man’s face, visit https://news.nationalgeographic.com/2018/02/ancient-face-cheddar-man-reconstructed-dna-spd/