April 27, 2012
Study Supports Theory That Migration Brought Agriculture To Europe
A new analysis of ancient DNA belonging to a quartet of Stone Age humans has shed new light on how agriculture may have spread from the Middle East into Europe, the Associated Press (AP) and AFP reported on Thursday.
The study, which was completed by researchers at a trio of Swedish and Danish universities and published in Friday's edition of the journal Science, looked at the genetic material from 5,000 year old bones belonging to one farmer and three hunter gatherers, according to those wire service reports. The remains had been obtained from different locations in Sweden and their lifestyles were discerned because of artifacts discovered at the sites."When the scientists compared the ancient DNA to that of modern-day Europeans, they found that the farmer´s DNA was most similar to Mediterranean populations like Cypriots and Greeks. In contrast, the hunter-gatherer DNA most closely resembled northerners like Finns," AP Science Reporter Malcolm Ritter said. "The simplest explanation for this pattern is that an ancient migration of farmers started in southern Europe and moved northward over many generations, said the researchers."
"We have been able to show that the genetic variation of today's Europeans was strongly affected by immigrant Stone Age farmers, though a number of hunter-gatherer genes remain," study co-leader Anders GÃ¶therstrÃ¶m, an assistant professor at the Uppsala University Evolutionary Biology Centre, said in a statement Thursday. "Many attempts, including using genetics, have been made to come to terms with the problem since the significance of the spread of agriculture was established almost 100 years ago. Our success in carrying out this study depended on access to good material, modern laboratory methods and a high level of analytical expertise."
GÃ¶therstrÃ¶m, along with fellow Uppsala University experts Pontus Skoglund and Mattias Jakobsson and colleagues at Stockholm University and the University of Copenhagen, sequenced nearly 250 million base pairs from a female agricultural worker identified as GÃ¶k4 and three-hunter gatherers from approximately 5,000 years ago as part of their research, Nature's Henry Nicholls said.
Their findings, he notes, are "strong evidence for the migration hypothesis."
"When you put these findings in archaeological context, a picture begins to emerge of Stone Age farmers migrating from south to north across Europe, and the result of this migration, 5,000 years later, looks like a mixture of these two groups in the modern population," Skoglund said in a separate press release. The results suggest that agriculture spread across Europe in concert with a migration of people. 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."
Image Caption: This is Ove Persson and Evy Persson at the Ajvide excavations in Gotland, Sweden. Credit: Photo taken by GÃ¶ran Burenhult