With their distinct genetic make-up and ancient language, the origin of people from the Basque Country in northern Spain and southern France has long been an enigma. Previously thought to be a population of unmixed hunter-gatherers that survived the influx of farmers from the Middle East around 6,000 years ago, new genetic evidence suggests that things aren’t quite so clear-cut.

Instead, it appears that the Basques' closest ancestors are early Iberian farmers who were descended from that first wave of Neolithic farmers, which then mixed with the local hunter-gatherers. The researchers think that the Basque people's unique characteristics survived in isolation as, after this first initial mingling of hunter-gatherers and farmers, the Basque people became separated from subsequent waves of farmers, first from the East then from the South, and continued instead to mix further with the local hunter-gatherers.

“We show that the hunter-gatherer genetic component increases with time during several millennia, which means that later farmers were genetically more similar to hunter-gatherers than their forefathers who brought farming to Europe,” explains Dr Torsten Günther, one of the lead authors of the study, in a statement. The research will be published in The Proceedings of the National Academy of Sciences.

Because the Basques are genetically distinct from the rest of Europe, and their language is what’s classed as a “pre-Indo-European” language (one that existed in prehistoric Europe before the dominant language type swept across the continent from the east), the region has always puzzled anthropologists. The researchers of this new study hoped to find answers in the 3,500 to 5,500-year-old remains of eight Iberian farmers discovered in the El Portalon cave in northern Spain.

The site shows remarkable preservation of artifacts, giving an incredible snap shot of Neolithic life. Archeologists have unearthed stone tools, ceramics, metal objects, and human and animal bones. But what’s so impressive is the preservation of organic remains, which allowed the scientists to extract and sequence the DNA of these ancient people.

“Our results show that the Basques trace their ancestry to early farming groups from Iberia, which contradicts previous views of them being a remnant population that trace their ancestry to Mesolithic hunter-gatherer groups,” says Professor Mattias Jakobsson of Uppsala University, who led the study. “The difference between Basques and other Iberian groups is these latter ones show distinct features of admixture from the east and from north Africa.”

The results of the study highlight the intricacies of the movements within Europe during the Neolithic, and how certain communities can become isolated and separated from others who aren’t far away geographically. It also helps to solve the longstanding puzzle of the Basques, and shows that they’ve remained relatively isolated for the last 5,000 years, but not much longer than that.

^{Main Image: Terre et Côte Basques/Flickr CC BY-NC-ND 2.0}

^{Image in text: Burial of a Neolithic child found in the El Portalon cave. It's thought he probably died of malnutrition, despite being buried alongside a complete calf. Credit: Eneko Iriarte}