Scientists used a wisdom tooth from a European hunter-gatherer’s skeleton to piece together his genome sequence.
The research gave them an unprecedented glimpse into modern humans that pre-date the rise of farming in Europe.
The Mesolithic man, who lived in Spain roughly 7,000 years ago, was found to have an unusual mix of blue eyes, dark black or brown hair and dark skin – according to the analysis of his genetic makeup. The findings were unexpected, especially since the mutation for blue eyes was thought to have arisen more recently than those for light skin colour.
“Before we started this work, I had some ideas of what we were going to find,” said Carles Laluzela-Fox, the lead researcher at the Institute of Evolutionary Biology in Barcelona.
“Most of those ideas turned out to be completely wrong,” Lalueza-Fox said of the surprising findings.
Artists may even need to re-think their works that depict humans in that age: “You see a lot of reconstructions of these people hunting and gathering and they look like modern Europeans with light skin. You never see a reconstruction of a mesolithic hunter-gatherer with dark skin and blue eye colour,” Lalueza-Fox said.
Scientists also believe the hunter-gatherer would have been lactose intolerant and had trouble digesting starchy foods – the invention of farming and an agricultural revolution would eventually change all that, transforming diets and lifestyles.
Tests on the DNA revealed that humans had already developed and carried mutations that boost the immune system’s ability to tackle various bugs and infections, as humans came into closer contact with animals through farming. Interestingly, some of these mutations continue to live on in modern Europeans even today.
The team of biologists began work on the human remains after a group of cavers stumbled upon two skeletons in a deep cave system in the Cantabrian mountains, northwest of Spain in 2006. The remains were identified as having belong to two men, most probably hunter-gatherers, in their early 30’s. Carbon dating put the remains at 7,000 years old.
Scientist chose the most well preserved of the two skeletons for their research. Several failed attempts to reconstruct the man’s entire genome, scientists utilised DNA found in the third molar.
Genetic testing by the Spanish team found that the genome of the hunter-gatherers were more closely matched with those living in northern Europe – in particular sweden and Finland.