As reported in the 27 April issue of the journal Science, an analysis of 5,000-year-old DNA taken from the Stone Age remains of four humans excavated in Sweden is helping researchers understand how agriculture spread throughout Europe long ago. According to Pontus Skoglund from Uppsala University in Sweden and colleagues, the practice of farming appears to have moved with migrants from southern to northern Europe.
     "We analysed genetic data from two different cultures - one of hunter-gatherers and one of farmers - that existed around the same time, less than 400 kilometres away from each other," said Skoglund. "After comparing our data to modern human populations in Europe, we found that the Stone Age hunter-gatherers were outside the genetic variation of modern populations but most similar to Finnish individuals, and that the farmer we analysed closely matched Mediterranean populations."
     "When you put these findings in archaeological context, a picture begins to emerge of Stone Age farmers migrating from south to north across Europe," said Skoglund. "And the result of this migration, 5,000 years later, looks like a mixture of these two groups in the modern population."
     "The results suggest that agriculture spread across Europe in concert with a migration of people," added Skoglund. "If farming had spread solely as a cultural process, we would not expect to see a farmer in the north with such genetic affinity to southern populations."

Edited from EurekAlert! (26 April 2012)