DAVID GREENE, HOST:
Humans began farming in earnest about 12,000 years ago. Scientists say this early farming took place in the Fertile Crescent. That's a vast region in the Middle East, stretching from the Persian Gulf to the Mediterranean Sea. This week, archeologists digging in the foothills of Iran's Zagros Mountains say they've uncovered one of the earliest farming communities found to date. They're getting a rare picture of one of the first human experiments with agriculture.
Here's NPR's Rhitu Chatterjee.
RHITU CHATTERJEE, BYLINE: The Zagros Mountains run along the border between Iran and Iraq. And for decades, they've been closed to researchers. But in 2009, a team of archaeologists from Iran and Germany began excavating in the foothills, close to Iraq.
NICHOLAS CONARD: It's a fairly exotic place, very semi-arid, rugged countryside.
CHATTERJEE: That's Nicholas Conard of the University of Tubingen. He says he and his colleagues began to dig through a gentle mound, about eight meters high. Before long, they'd hit pay dirt. The sediments in the mound were rich with artifacts, some going back 12,000 years.
CONARD: Sculpted clay objects, clay cones, depictions of animals and humans.
CHATTERJEE: There were stone tools, too, including mortars and pestles, some clearly used for grinding food. Then there were seeds and grains, hundreds of them, charred but otherwise intact and well-preserved.
CONARD: They look like the lentils that you buy at the store, or, you know, pieces of wheat or barley that you might have seen.
CHATTERJEE: Now, Conard is no botanist. He specializes in stone tools. So to double-check, he sent the samples of the plant materials to a colleague back at his university in Germany. Simone Riehl is an archaeobotanist.
SIMONE RIEHL: That was a fantastic feeling when I first got these plant remains under the microscope, because we usually do not have that many plant remains from these early sites. So that was really was great to work with that material.
CHATTERJEE: The samples spanned a period of 2,000 years. Riehl soon confirmed that in the beginning, the farmers were growing lentils, barley, peas and a range of other crops.
RIEHL: They were basically cultivating what we consider as the progenitors of our modern crops.
CHATTERJEE: In other words, these were not domesticated plants. This ancient community was simply taking seeds and plants from the wild and growing them in fields. They hadn't started breeding crops yet and selecting varieties for yield and other desirable qualities.
RIEHL: We do not have any clear evidence that it was very conscious in the beginning.
CHATTERJEE: But 2,000 years later, they had clearly started breeding emmer wheat, so that the ears were stronger and made harvesting a lot easier.
Riehl's findings, which are published in the latest issue of the journal Science, give a rare close-up picture of the early evolution of farming.
Melinda Zeder is a curator of Old World Archaeology at the Smithsonian Museum of Natural History in Washington, D.C.
MELINDA ZEDER: It's allowing us to push back our picture of early agriculture to these very, very initial stages, when people are beginning to play around with plants and their environment.
CHATTERJEE: Zeder says the findings change our understanding of where people first started farming. Until now, she says scientists had thought agriculture began in the western parts of the Fertile Crescent. This new find is far to the east.
ZEDER: It really forces us to broaden our viewpoint on early agriculture to include this vast region of the whole Fertile Crescent.
CHATTERJEE: She says the findings confirm that rather than starting in one place and spreading, farming began with many different communities experimenting with agriculture around the same time.
Rhitu Chatterjee, NPR News.