Archaeologists Brendan Foley, Theotokis Theodoulou and Alex Tourtas excavate the Antikythera shipwreck skeletal remains, assisted by Nikolas Giannoulakis and Gemma Smith. (Brett Seymour/EUA/WHOI/ARGO)

Brendan Foley was only three minutes into his first dive on his first day at the site of the 2,100-year-old Antikythera shipwreck when a colleague came swimming over to him.

"You've gotta see this," they said. "We found bones. We found a skull!"

Archaeologists have been scouring the site in Greece for more than 100 years, and only a few scattered human remains have shown up during that time. Foley swam in the direction his colleagues pointed, trying not to get his hopes up.

But what he saw half-buried in the sediment was even more than he could have hoped for: "We have the first human skeleton recovered from an ancient shipwreck since the advent of ancient DNA studies," Foley said. "We can investigate this individual in a way that was never possible before."

Researchers studying the shipwreck Antikythera have discovered a nearly complete skeleton. (EUA/WHOI/ARGO)

The discovery of the long-buried bones in the dark, chilly water 150 feet beneath the surface of the Mediterranean could give new insight into what is arguably the ancient world's most famous shipwreck. Discovered by sponge divers in 1901, the wreck has yielded a king's ransom in ancient bronze statues, silver coins, ceramic jars, marble sculptures and decadent gold jewelry. Most precious of all is the mysterious Antikythera mechanism, a complex, clockwork instrument that modeled the passage of time and the movements of celestial bodies and has been called the world's oldest computer. It is far and away the most sophisticated piece of machinery from the ancient world, and scientists still have no idea who made it — or why.

DNA analysis of the newly excavated skeleton could offer clues to that mystery and countless others associated with the shipwreck.

"Now we’re face to face with someone who sailed that ship, face to face with someone who might have handled the mechanism," Foley said. "We can look through his eyes at the voyage, at the wreck, at the whole first century B.C."

Fragments of the 2,100-year-old Antikythera mechanism, believed to be the earliest surviving mechanical computing device, are displayed at the National Archaeological Museum in Athens on June 9 , 2016. The fragments were found in the shipwreck. (Petros Giannakouris/AP)

Foley, an underwater archaeologist at the Woods Hole Oceanographic Institution, has spent several years surveying the wreck, trying to reconstruct how it would have looked 2,100 years ago in hopes of finding new treasures — and perhaps even a second Antikythera mechanism. In 2012, he and his colleagues identified a second, smaller wreck, probably dated around the same time as the first. They found lead sheets from the hull of the main ship that were sourced from mines in northern Greece, and deduced from the preservation of the human remains that they must have been buried by organic material right after they sank. Those facts, paired with a cup uncovered by an earlier expedition that bore the Greek name "Pamphilos," let Foley to begin imagining the circumstances of the ship's demise. 

"It's quite possible this was a grain-carrying ship," he said. "They were the supertankers of the ancient world."

Such ships frequently carried tourists, like the Greek man Pamphilos, who must have been both wealthy and literate to have a cup with his name and know how to read it. Laden with cargo and passengers, the ship could have been sailing toward Rome when it passed through the narrow, reef- and rock-chocked passageway between the islands Antikythera and Crete, just south of Greece.

"They were sailing along, it was probably that proverbial dark and stormy night, and they didn’t know how close they were to Antikythera, and before they knew it they just ran into the cliff," Foley said. "And they were lost in an instant."

The skeleton Foley and his colleagues just uncovered was probably caught between decks as the ship went down.

Antikythera project co-directors Theotokis Theodoulou and Brendan Foley inspect the skeletal remains: skull and upper jaw with teeth, two femurs, radius, ulna, ribs. (Brett Seymour/EUA/WHOI/ARGO)

A preliminary analysis of the remains — which include two femurs, the long bones of the forearm and most of the skull — suggest that they belonged to a young man, probably in his mid- to late 20s. They are brittle, but well-preserved, and stained a deep red by iron.

Foley speculates about what that could mean: "Maybe he had iron fasteners on his clothing? Or things in his pocket or purse? Or maybe this is a slave and he's shackled, and that's why there's so much oxidized iron around."

DNA analysis should reveal more. As soon as the skeleton was found, Foley contacted Hannes Schroeder of the Natural History Museum of Denmark, one of the few places in the world with the technology to sequence highly degraded ancient DNA. Scientists have never successfully sequenced human material that had been submerged in so much saltwater for so long; though remains were uncovered from the 16th- and 17th-century shipwrecks Mary Rose and Vasa, those were found before the advent of next-generation DNA sequencing, which is much more powerful than previous methods.

"It's tricky, because this is such a rare find that we don't have a lot of experience in the field generally," Schroeder said.

Diving operations manager Phillip Short inspects amphoras on the Antikythera shipwreck. (Brett Seymour/EUA/WHOI/ARGO)

On Schroeder's advice, Foley and his colleagues removed the bones from the sea floor one by one. Each was photographed and 3-D-modeled, then placed in a plastic bag with sea water to keep them as close as possible to the conditions under which they survived for 2,100 years.

Now the scientists are waiting on approval from the Greek government to start testing the remains.

"It's a little bit of a race against time," Schroeder said. "Those remains were preserved down there at 50 meters below sea level. If you started changing their environment, they will start degrading quickly."

But Schroeder is optimistic, largely because both of the skeleton's petrous bones are still intact. These ultra-dense bones, which help form the inner ear, are some of the best for recovering ancient DNA. Those results will allow the team to identify the skeleton's ethnicity and begin to flesh out the man behind those scattered bones.

"This kind of thing is really why I became a scientist," Foley said. "This is it."

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