Early spread of Neolithic domesticated sheep to the heart of Central Asia

PICTURE: An artistic depiction of a Neolithic cattle breeder at the Obishir lookout more

Credit: Ettore Mazza

Along the Tian Shan and Alay mountain ranges in Central Asia, sheep and other domestic livestock make up the basic economy of modern life. Although it was here that the movements of their ancient predecessors helped shape the large Silk Road trade networks, domestic animals were thought to have come to the region relatively late. A new study, published today in the journal Nature: human behavior, reveals that the roots of animal domestication in Central Asia go back at least 8,000 years – making the region one of the oldest continuously inhabited pastoral landscapes in the world.

The domestication of sheep, goats, and cattle first occurred in the Fertile Crescent of Mesopotamia and the nearby mountain zones of western Asia about 10,000 years ago, in close proximity to the first domestication of crops such as wheat and barley. This innovation in human survival, known as the Neolithic Revolution, spread north to Europe and south to Africa and India, transforming human societies on three continents. But until recently, this dramatic spread of native plants and animals did not seem to reach east to the rich mountain zones of Central Asia, where – despite their over-importance in the later millennia of the Bronze Age and beyond – there was little evidence of Neolithic expansion.

That changed when a joint team of international scientists, led by Dr. Svetlana Schnaider from the Russian Institute of Archeology and Ethnography (RAS-Siberia, Novosibirsk) and others. Aidom Abdykanova from the American University of Central Asia (Kyrgyzstan), decided to visit rockhelter Obishir V, tucked into a mountain abyss along the southern border of Kyrgyzstan with Uzbekistan. At this place, which was first discovered and excavated by Soviet archaeologists in the 20th century, an unusual set of stone tools emerged from which someone seemed to have been used to process grain. Furthermore, sprinkled over the layers of the geological layers of the site were the crushed remains of what appeared to be sheep and goats.

Could this be evidence of the ancient Neolithic movement of undocumented domestic animals deep into the interior of Central Asia? To find out, Shnaider and Abykanova teamed up with lead author Dr. William Taylor, a specialist in the study of animal domestication at the University of Colorado-Boulder Museum of Natural History and the Max Planck Institute for the Science of Human History, along with a team of international experts from across Europe and the United States. After radiocarbon dating of the bones and teeth from the site, it became clear that the oldest cultural layer was dated at least approximately. 6000 BC, or more than 8,000 years ago – three millennia before domestic animals were thought to have arrived in Central Asia.

Burns, traces of cuts, and other changes in animal bones have been shown to be slaughtered, while patterns of microscopic seasonal deposits in animal tooth cementum indicate that they were slaughtered in the fall, which is common in many livestock societies. But because the bones were very fragmented, the species could not be identified using standard anatomical analysis. Instead, the researchers applied an interdisciplinary approach using the paleogenomics and fingerprints of collagen peptides to identify animal remains. Comparing their results with the genomes of wild and domestic sheep species from across Eurasia, the researchers made a shocking discovery.

“With each new line of evidence, it became clearer … it wasn’t wild sheep – it was domestic animals,” Taylor says.

For those who have worked for years to understand the prehistory of Central Asia, the results are astounding.

“This discovery only illustrates how much mystery still remains regarding the prehistory of Inner Asia – the cultural crossroads of the ancient world,” says Dr. Robert Spengler of the Max Planck Institute – co-author of the study and author of the book Fruits from the sand: The silk path is the origin of the food we eat.

Future work will be needed to understand the full impact of the study findings and their implications on the rest of ancient Eurasia. Shnaider plans to return to Obishir next summer to look for clues and determine if other domestic animals, such as cattle, or domestic plants, such as wheat and barley, have spread to Kyrgyzstan from Mesopotamia in the deep past. In addition to the European Research Council Award, project partner and co-author dr. Christina Warinner (Harvard / MPI-SHH) is leading the effort to investigate whether these first Central Asian sheep spread elsewhere in the region and whether they were used to produce dairy or wool.

“This job is just the beginning,” Taylor says. “By applying these interdisciplinary techniques from archaeological science, we begin to unlock traces of Central Asia’s past.”

###

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of the news published on EurekAlert! contribution to institutions or for the use of any information through the EurekAlert system.

.Source