A study of ancient DNA from Europeans between 1,700 and 45,000 years ago suggests that 63 percent of them had dark skin and 8 percent had pale skin, with the rest somewhere in between. It was only around 3000 years ago that individuals with intermediate or pale skin started to become a majority.
Experts at the University of Ferrara in Italy claim that as recently as 1,700 years ago, during the time of the mighty Roman Empire, light skin wasn’t as commonplace as dark skin, their DNA evidence suggests.
Light skin tones originally appeared in Sweden in the Mesolithic period—starting about 14,000 years ago—but remained rare, according to the researchers.
The Copper and Bronze Ages (about 7,000 to 3,000 years ago) saw continued increases in light pigmentation—but darker skin types remained widespread.
“The shift towards lighter pigmentations turned out to be all but linear in time and place, and slower than expected,” the researchers say.
By the Iron Age (about 3,000 to 1,700 years ago), light skin was nearly as frequent as dark skin, particularly in Northern and Central Europe. However, dark pigmentation remained common in regions such as Italy, Spain and Russia.
For the study, the researchers analyzed ancient genomes (the entire set of DNA instructions) of 348 individuals who lived between 45,000 and 1,700 years ago.
All Europeans had dark skin in the Paleolithic period
Overall, nearly all European individuals had dark pigmentation during the earliest period (Paleolithic, around 45,000 to 13,000 years ago), with only one exception showing an intermediate skin color.
In Neolithic-era Britain (starting approximately 8000 BC), the majority of people (about 85 percent) were dark-skinned. But by the Copper Age (from about 3500 BC) there was a 50/50 split of dark-skinned people and light-skinned people.
By the Bronze Age (2000 BC to 500 BC), about 50 percent of Brits had an ‘intermediate’ skin color, while 25 percent were light-skinned and 25 percent were dark-skinned.
Meanwhile, France was approximately 65 percent dark-skinned during the Mesolithic period (from around 12,000 years ago), while 35 percent were classed as light-skinned.
By the Neolithic period, France was about 85 percent dark-skinned and the remainder intermediate—but 100 percent light-skinned by the Bronze Age.
Why Europeans evolved with light pigmentation
Scientists know that modern humans (Homo sapiens) evolved in Africa but migrated out of the continent 60,000 to 70,000 years ago, eventually reaching Europe and Asia.
The scientists say light pigmentation became more common as Homo sapiens dispersed from Africa into regions with lower ultraviolet (UV) radiation. These early Europeans evolved to become lighter-skinned as they had to adapt to a continent that saw less sunshine.
Lighter skin allows more UV light to penetrate, helping the body produce vitamin D, which is crucial for maintaining strong bones and muscles.
In turn, darker skin, which contains more black-brown pigments than fair skin is better protected against UV-induced damage from excessive sunlight.
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