A team of archaeologists from the University of Chicago's Oriental Institute has joined a team of Syrian colleagues in excavating a key site from the prehistoric society that formed the foundation of urban life in the ancient Middle East.
The site already has yielded evidence of trade in obsidian, rich agricultural production and the development of copper processing - all of which flourished long before people domesticated pack animals for transportation or invented the wheel. The early culture also spawned a social elite that engaged in trade with far-flung regions and used stone seals to mark ownership of goods.
The American and Syrian archaeologists are digging at the long-known, but previously unexcavated mound of Tell Zeidan, which is one of the largest sites of the Ubaid culture in northern Mesopotamia. Tell Zeidan dates from between 6000 and 4000 B.C. and is expected to shed much light on the Ubaid period (about 5300-4000 B.C.), which immediately preceded the world's first urban civilizations in the ancient Middle East.
"This enigmatic period saw the first development of widespread irrigation agriculture, of centralized temples, powerful political leaders and the first emergence of social inequality as communities became divided into wealthy elites and poorer commoners," Gil Stein, Director of the Oriental Institute and a leader of the expedition.
"This was the time when people first invented the technology of metallurgy, and was known as Copper-Stone age," he added.
Stein said the location's potential for further discoveries is so great that the project is likely to last for decades.
Scholars have long understood the site's importance, and are watching its excavation with keen interest. One of the first scholars to note the importance of the site was the famed British archaeologist Sir Max Mallowan, who was the husband of writer Agatha Christie.
"Understanding developments that took place in ancient Mesopotamia during the Ubaid period is absolutely essential if we are to gauge the magnitude and tempo of the social transformations that eventually culminated in the origins of cities and states in the ancient Near East in the fourth millennium B.C.," said Guillermo Algaze, Professor of Anthropology at the University of California, San Diego, and a specialist on the emergence of urbanism in the Middle East. Algaze is an outside expert not involved in the current project.
"Because of its size and depositional history, Zeidan offers a historical opportunity to learn more about the Ubaid period than has been heretofore possible," Algaze said. "Accordingly, Stein's work at this unique site has the potential to revolutionize current interpretations of how civilization in the Near East came about."
Thirty-one acres in extent, Tell Zeidan is situated where the Balikh River joins the Euphrates River in modern-day Syria. The location was at the crossroads of major trade routes across ancient Mesopotamia that followed the course of the Euphrates River valley.
Stein said Tell Zeidan may have been one of the largest Ubaid temple towns in northern Mesopotamia, and that it was as large or larger than any previously known contemporary Ubaid towns in the southern alluvial lowlands of the Tigris and Euphrates rivers in what is today southern Iraq. However, because the site was not occupied after about 4,000 B.C., the prehistoric strata of Tell Zeidan are immediately accessible beneath the modern-day ground surface instead of being buried beneath layers of deposits from later periods.
"This means that, for the first time, archaeologists can excavate broad areas of an Ubaid temple town to understand how a proto-urban community actually functioned in the sixth-fifth millennia B.C.," Stein said.
The new excavations Tell Zeidan reveal the emergence of an elite that possessed the political power necessary for communities to move from self-sufficient village life to societies dependent on trade and capable of acquiring luxury goods, Stein said.
Stein, a noted archaeologist who is a specialist on the Ubaid culture, began excavating the site in 2008 and returned in 2009. He is the American co-director of the Joint Syrian-American Archaeological Research Project at Tell Zeidan, and Muhammad Sarhan from the Raqqa Museum in the nearby provincial capital of Raqqa is the Syrian co-director.
"The two-millennium-long occupation spans four key periods: two phases of the late Copper Age on top, the Ubaid period in the middle and the Halaf period at the bottom," Stein said.
The excavations so far show that the transitions between these periods were peaceful, including the period in which the influence of the Ubaid culture spread from its south Mesopotamian homeland up the Euphrates River into north Syria.
"One of our most remarkable finds was a stone stamp seal depicting a deer. The seal was unusually large, about two inches by two-and-a-half inches," Stein said. The seal was carved from a red stone not native to the area, but was similar in design to a seal found 185 miles to the east near Mosul in northern Iraq.
"The existence of very elaborate seals with near-identical motives at such widely distant sites suggests that in this period, high-ranking elites were assuming leadership positions across a very broad region, and those dispersed elites shared a common set of symbols and perhaps even a common ideology of superior social status," he said.
The seals were used as stamps to indicate possession of goods in the period before writing.
The team found obsidian blades and chips wasted during the production of the blades.The high-quality volcanic glass had to be brought to the community from sources 250 miles away in what is now Turkey. The greenish-black color and chemical composition show that it came from mines in the eastern part of the country.
The people in Tell Zeidan also had access to copper ore from sources near modern-day Diyarbakir, Turkey, about 185 to 250 miles away. Those materials were smelted at Tell Zeidan to produce metal tools that represent the most advanced technology of the fifth millennium B.C. People must have transported the material on their backs, however, as Tell Zeidan flourished at a time before donkeys were domesticated.
The wealth of the community came from irrigation-based agriculture, trade and manufacturing. Stein said the team found countless flint sickle blades-easily recognizable from the glossy sheen created when silica in the wheat's stems polished the blades during harvest. The people used bitumen, a tar substance obtained from pits 43 miles away, to secure the blades onto handles.
Along with the advanced technology, a wealthy ruling class and individual identification by stamp seals, the people at Tell Zeidan also built large public structures of mud bricks.
The National Science Foundation supported the project.