Saturday, December 18, 2010

Fertile Crescent farmers took DNA to Germany

Artistic impression of a neolithic farmer in Central Europe. Held in the State Museum of Prehistory in Halle, Saxony-Anhalt, Germany (Source: Karol Schauer/PLoS)
DNA evidence suggests that immigrants from the Ancient Near East brought farming to Europe, and spread the practice to the region's hunter-gatherer communities, according to Australian-led research.

A genetic study of ancient DNA, published in PLoS Biology today, adds crucial information to the long-running debate about how farming was introduced to Europe's nomadic hunter-gatherer societies almost 8000 years ago.

An international research team, led by University of Adelaide experts, compared ancient DNA from the remains of Early Neolithic farmers at a burial site in central Germany with a large genetic database of European and Eurasian populations.

They found that these early farmers had a unique and characteristic genetic signature, suggesting "significant demographic input from the Near East during the onset of farming".

Sometimes referred to as the Fertile Crescent, the Near East would include modern-day Iraq, Jordan, Syria and Lebanon, says study leader Dr Wolfgang Haak, genographic project senior research associate at the Australian Centre for Ancient DNA at the University of Adelaide.

The revolutionary element of this study was the addition of ancient DNA , explains Professor Alan Cooper, director of the Centre for Ancient DNA, as previously researchers could only use genetic data from modern populations to examine this question.

"We have never had a detailed genetic view of one of these early farming populations - there's been a lot of inference around it... but it's all been guesswork" he says.
Migration from Anatolia and near East

Using the new high-precision ancient DNA analysis, researchers were also able to determine a possible migration route the farmers took from the Near East and Anatolia into Central Europe.

Farming first originated about 11,000 years ago in the Near East and then spread across Europe during the Neolithic period, the researchers explain.

"Whether it was mediated by incoming farmers or driven by the transmission of innovative ideas and techniques remains a subject of continuing debate in archaeology, anthropology, and human population genetics," they write in PLoS Biology.

"[This] really answers this long-running debate about whether people picked up ideas or picked up and moved", says Cooper.

Haak says these latest findings might not completely settle the debate on the origins of farming in Europe, but they would "push it in a certain direction".

Haak is keen to see other research teams build on this proof of concept study, building a picture about this transitional period in other regions and helping to put the pieces of the jigsaw together globally.

Meanwhile, Haak and colleagues at the Australian Centre for Ancient DNA want to discover how communities in this region in central Germany evolved over the next 3000 to 4000 years leading up to the Bronze Age.

"The early farmers are still quite different to modern day populations from the same region," he says, "so that means something must have happened after that."

The project involved researchers from the University of Mainz and State Heritage Museum in Halle, Germany, the Russian Academy of Sciences and members of the National Geographic Society's Genographic Project.
Rebecca Jenkins
ABC

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