A genetic analysis of an ancient European hunter-gatherer reveals that his face was a striking combination of dark skin and blue eyes.
Spanish researchers recovered DNA material from the 7,000-year-old skeletal remains of two specimens, nicknamed La Brana 1 and La Brana 2.
Lead researcher Carles Lalueza-Fox, with the Spanish National Research Council, said the genetic tests on a molar tooth belonging to one specimen, La Brana 1, indicate that scientists' assumptions about when Europeans developed light complexions were way off the mark.
"The biggest surprise was to discover that this individual possessed African versions in the genes that determine the light pigmentation of the current Europeans, which indicates that he had dark skin," Lalueza-Fox said.
Scientists had believed that Europeans with light complexions evolved early during the Upper Palaeolithic era (between 50,000 and 10,000 years ago), soon after Europeans left Africa and arrived in Europe. But the latest findings show that La Brana 1 still had dark skin and had been around the continent for 40,000 years, meaning fair skin probably evolved millennia later.
The findings are published in the journal Nature.
Modern relatives in Sweden, Finland
The early man was the first European hunter-gatherer to have his genome fully sequenced.
Lalueza-Fox said it's difficult to determine the exact shade of the man's complexion, but that he very likely had dark hair — either black or brown — as well as the gene mutation for blue eyes.
One theory of how light skin emerged is that changes in diet may have been a big contributing factor, as farming became more commonplace. La Brana 1 lived in a time that predates agriculture and his genome shows he was lactose-intolerant and unable to digest starch.
Dark skin produces less vitamin D during exposure to the sun. The rise of food production may have meant lower dietary intake of vitamin D, giving Europeans an evolutionary incentive to adopt lighter complexions, allowing them to produce more vitamin D.
Lalueza-Fox's team traced the man's closest modern-day relatives to northern European countries like Sweden and Finland.
La Brana 1 and La Brana 2 were discovered by hikers in 2006 in a cave in La Braña-Arintero, in the Cantabrian Mountains of Spain. The cool, dark conditions helped to preserve the remains.
La Brana 2's DNA was not analyzed in the same way, because it was more degraded due to contact with moisture.