A recent DNA study challenges long-held beliefs about the evolution of skin color in ancient Europeans, revealing that the majority may have had dark skin as recently as 3,000 years ago. Led by Guido Barbujani of the University of Ferrara in Italy, the study examined the genomes of 348 individuals who lived between 1,700 and 45,000 years ago.
Barbujani's team investigated pigmentation traits in these ancient Europeans by extracting DNA from their bones and teeth. Researchers combined this DNA with forensic techniques that predict skin, eye, and hair color based on genetic markers. Scientists used probabilistic methods on often fragmented and degraded ancient DNA to estimate these traits.
"For much of the tens of thousands of years covered by the DNA samples, 63% of ancient Europeans had dark skin, while only 8% had light skin," said Barbujani, according to Origo. The remaining individuals had skin tones between dark and light. Light-skinned individuals became more common in Europe only about 3,000 years ago. Even during the Copper and Iron Ages, approximately 5,000 to 3,000 years ago, half of the analyzed individuals still had dark or medium skin color.
It was previously believed that modern humans arrived in Europe about 45,000 years ago and quickly developed lighter skin to adapt to low sunlight levels. Researchers explained that lighter skin tones only began to spread after that time.
Paleobiologist Nina Jablonski, an anthropologist at Pennsylvania State University, commented on the study's implications. "Their skin color probably varied nearly as much as modern humans," she said, according to Helsingin Sanomat. Jablonski estimates that previously, sufficient vitamin D was obtained from food, which may explain why darker skin persisted longer than previously thought. "Most hunter-gatherers apparently got enough vitamin D from food in the past," Jablonski said. According to her, the increase of light skin only about 3,000 years ago may be related to changes in diet.
As populations grew and farming became widespread, diets may have provided less vitamin D, making the ability to synthesize it through the skin more advantageous. The human body needs vitamin D for normal immune defense, and darker skin allows less ultraviolet radiation to penetrate.
Advancements in DNA analysis have made it possible to sequence the DNA of individuals who lived thousands of years ago. Many DNA investigation methods developed in forensic science are now applied to study ancient remains. Using these methods, researchers concluded as early as 2018 that a man who lived in Britain about 10,000 years ago was dark-skinned.
The study also sheds light on famous ancient individuals. Ötzi, the glacier mummy who lived 5,300 years ago, had dark skin before he died in the Alps. His skin color may have been genetically darker than that of modern Southern Europeans but lighter than that of modern Sub-Saharan Africans.
Some Neanderthals may have had light skin even before modern humans arrived in Europe, suggesting that the evolution of skin pigmentation is more complex than previously understood. Skin cells can form a precursor of vitamin D when exposed to ultraviolet light, supporting the belief that lighter skin allows more ultraviolet light to penetrate.
"Until a few years ago, it was assumed that the skin of modern humans migrating to Europe became lighter much earlier than 45,000 years ago," Jablonski explained. Light-skinned individuals were found more frequently in samples taken from individuals who lived closer to modern times.
The article was written with the assistance of a news analysis system.