Ancient DNA Reveals Surprising Truths About European Skin Color Evolution

For decades, scientists believed that early modern humans in Europe quickly evolved pale skin to adapt to dim sunlight. However, a new study challenges this assumption, revealing that most of Europe's inhabitants had dark skin for much of its history. Only around 3,000 years ago did lighter skin tones become dominant. Skin color evolution is complex. Early humans in Africa likely had dark skin for protection from intense UV radiation. As humans migrated north, lighter skin became advantageous for vitamin D production. The new study, analyzing 348 individuals from 45,000 to 1,700 years ago, shows this transition was not straightforward. Even during the Copper and Iron Ages (5,000 to 3,000 years ago), half of the individuals analyzed had dark or intermediate skin tones. Ötzi, the 5,300-year-old glacier mummy, had darker skin than modern South Europeans but lighter than Sub-Saharan Africans. "It's the darkest skin tone that has been recorded in contemporary European individuals," said anthropologist Albert Zink. In 2018, the 10,000-year-old Cheddar Man from Britain was found to have dark-brown skin and blue eyes. The new study, led by Guido Barbujani at the University of Ferrara in Italy, found that 63% of ancient Europeans had dark skin, 8% had pale skin, and the rest fell in between. These findings are based on DNA extracted from bones and teeth, combined with forensic techniques. The researchers used a probabilistic method to estimate pigmentation traits from ancient DNA, testing their approach on the Ust'-Ishim man from Siberia (45,000 years old) and an individual from Sweden (9,000 years old). They found their method reliably predicted pigmentation traits even with limited genetic information. The first signs of lighter pigmentation appeared in the Mesolithic (14,000 to 4,000 years ago) in Sweden and France. By the Bronze Age (7,000 to 3,000 years ago), the proportion of dark-skinned individuals had dropped to about half. Lighter skin tones only became dominant in the Iron Age (3,000 to 1,700 years ago). The spread of Neolithic farmers from Anatolia around 10,000 years ago, carrying genes for lighter skin, played a significant role. Localized migration and admixture also influenced skin color. Light eyes peaked in frequency during the Mesolithic, before lighter skin became common. The first instances of blonde and red hair appeared in the Neolithic and Bronze Age. The traditional explanation for lighter skin -- maximizing vitamin D production -- may not be the whole story. Dietary changes, as humans transitioned to agricultural communities and consumed fewer vitamin D-rich foods, may have also driven the evolution of lighter skin. Modern Europeans did not inherit pale skin from Neanderthals, as lighter skin evolved independently in modern humans. The study identified variants in the genes TYR and SLC24A5 associated with lighter skin. These variants were absent in the Paleolithic Ust'-Ishim man but present in a Bronze Age individual from Hungary with light skin, blue eyes, and blonde hair. While ancient DNA provides direct evidence, researchers have also looked to art for clues. However, relying on artistic representations can be misleading. The evolution of human skin color reflects the journeys, environments, and genetic legacy of our ancestors.