Day By Day

Tuesday, November 15, 2005

DNA and Human Migration -- The Spread of Agriculture in Europe

Science Daily reports:

Earliest European Farmers Left Little Genetic Mark On Modern Europe

The farmers who brought agriculture to central Europe about 7,500 years ago did not contribute heavily to the genetic makeup of modern Europeans, according to the first detailed analysis of ancient DNA extracted from skeletons of early European farmers.

The passionate debate over the origins of modern Europeans has a long history, and this work strengthens the argument that people of central European ancestry are largely the descendants of "Old Stone Age," Paleolithic hunter-gatherers who arrived in Europe around 40,000 years ago rather than the first farmers who arrived tens of thousands of years later during the Neolithic Age.

This paper appears in the 11 November 2005 issue of the journal Science published by AAAS the nonprofit science society.

The researchers from Germany, the United Kingdom and Estonia extracted and analyzed DNA from the mitochondria of 24 skeletons of early farmers from 16 locations in Germany, Austria and Hungary. Six of these 24 skeletons contain genetic signatures that are extremely rare in modern European populations. Based on this discovery, the researchers conclude that early farmers did not leave much of a genetic mark on modern European populations.

"This was a surprise. I expected the distribution of mitochondrial DNA in these early farmers to be more similar to the distribution we have today in Europe," said Science author Joachim Burger from Johannes Gutenberg Universität Mainz in Mainz, Germany.

"Our paper suggests that there is a good possibility that the contribution of early farmers could be close to zero," said Science author Peter Forster from the University of Cambridge in Cambridge, UK.

Read it here.

John Hawks is skeptical about these results. Read his comments here.

Athena at Rites of Passage is also not convinced. [here]

So the old question of whether the spread of agriculture into Central Europe from the Balkans was a result of cultural diffusion or population replacement is still up in the air. Once again we have journalistic reports of a sensational breakthrough that on closer examination is far less conclusive and important than is claimed.

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