At a sprawling Bronze Age cemetery in southern Jordan, archaeologists have developed a unique way of peering into the murky world of antiquities looting: With aerial photographs taken by a homemade drone, researchers are mapping exactly where - and roughly when - these ancient tombs were robbed.
Based on such images and conversations with some looters whose confidence they gained, archaeologists try to follow the trail of stolen pots and other artifacts to traders and buyers. They hope to get a better understanding of the black market and perhaps stop future plunder.
It's sophisticated detective work that stretches from the site, not far from the famed Dead Sea in Jordan, to collectors and buyers the world over.
The aerial photography detects spots where new looting has taken place at the 5,000-year-old Fifa graveyard, which can then sometimes be linked to Bronze Age pots turning up in shops of dealers, said Morag Kersel, an archaeologist at DePaul University in Chicago. Kersel, who heads the "Follow The Pots" project, also shares the data with Jordan's Department of Antiquities, to combat looting.
On a recent morning, team members walked across ravaged graves, their boots crunching ancient bones, as a tiny, six-bladed flying robot buzzed overhead. In recent years, drone use in archaeology has become increasingly common, replacing blimps, kites and balloons in surveying hard-to-access dig sites, experts said.
Chad Hill, an archaeologist at the University of Connecticut who built the drone, piloted it over a part of the graveyard that had not been mapped yet. The drone snapped photographs that allowed Hill to see in great detail how looting altered the landscape.
"We can see the change through time, not just if 'a huge pit has been dug' but where different stones have moved," Hill said. "It's a level of resolution of spatial data collection that's never really been possible until the last couple of years."
As the drone's batteries ran low, Hill overrode the automatic pilot and guided the landing with a remote control. Flipping the drone on its back, he checked the camera, nodding approvingly at the afternoon's work.
The cemetery in Jordan's Dead Sea plain contains about 10,000 graves, part of the vast archaeological heritage of the region.
It looks like a moonscape as a result of looting, with about 3,700 craters stretching to the horizon and strewn with shards of skeletons and broken ceramics. Looters typically leave human remains and take only well preserved artifacts.
"I spend my days stepping on dead people," said Kersel, picking up a broken shell bracelet, presumably from ancient Egypt.
An underlying cause for looting is high unemployment, said Muhammed al-Zahran, director of the nearby Dead Sea Museum. "Looting happens all across the region," he said.
In Jordan, unemployment is 12 percent, and it's twice as high among the young.
Yet stolen antiquities rarely enrich local looters, said Neil Brodie, a researcher at the University of Glasgow's Scottish Centre for Crime and Justice Research.
Rather, the profits end up in Europe or America, Brodie said, describing high markups as the artifacts move from looter to middleman, dealer and then customer.
Brodie studied looting at another site in Jordan, the ruins of the early Bronze Age community of Bab adh-Dhra, though without the help of drones.
He estimated that diggers were paid about $10,500 for 28,084 pots that were subsequently sold in London for over $5 million, sometimes marketed as "Old Testament" artifacts.
An artifact that later sold for $275,000 was initially traded for a pig, Brodie's research showed. And he also found that a dancing Hindu deity bought for about $18 sold eventually for $372,000.
Some of the artifacts stolen from Jordan's sites, including tombstones, end up in neighboring Israel, said Eitan Klein, a deputy at the Israeli Antiquities Authority's robbery unit.
Kersel, from the "Follow the Pots" project, said looters told her they sell their goods to middlemen from the Jordanian capital of Amman or the southern town of Karak. She said the trail stops with the shadowy middlemen, but that she can sometimes pick it up on the other end, by comparing the looting timeline with what eventually ends up on the market all across the world.
In addition to monitoring the cemetery, Kersel also teaches local workshops on profiting from antiquities legally, including by making and selling replicas, to discourage robbing graves.
Yet, looting will be difficult to stop as long as demand remains high, she said.
"People don't ask the sticky questions about where artifacts come from," said Kersel, standing inside a robbed grave in Fifa. "They just want to own the piece regardless of what kind of background the artifact has, and that is what causes people on the ground to loot."