On August 31, marine archaeologist Brendan Foley’s diving team made a spine-tingling discovery in the bottom of the Aegean Sea: a human skeleton. The remains were part of a famous, ancient shipwreck estimated to have occurred sometime in the first century BC. And earlier this week, an ancient-DNA expert brought in by Foley confirmed that the bones had been preserved well enough to offer scientists, for the first time, a realistic chance finding a 2,000-year-old shipwreck victim’s DNA sample. As Jo Marchant reports in Nature News, such an analysis can potentially fill many gaps in our minimal knowledge about population movements in that era.
In 1900, Greek sponge divers first stumbled upon the shipwreck off the island of Antikythera. They alerted the government and the navy, who spent the next couple years salvaging artefacts from the site. Besides bronze statues, marble sculptures and showy pieces of glasswork, they also unearthed what is today considered to be the world’s first “analogue computer”. The level of complexity of this device with its gears, dials and wheels was shocking to historians because it did not seem to fit in with our imagining of those times.
Later, it emerged that the Antikythera mechanism – as it was called – was used to show the lunar phases and the positions of the sun, moon and planets on any given date. The enigma surrounding this device highlighted to historians and scientists that the Antikythera shipwreck could serve as a window to a past we wrongly think we know a lot about.
However, the next large scale investigation into the site occurred only in 1976. This time, too, it did not disappoint. The French explorer Jacques-Yves Cousteau discovered hundreds more artefacts – coins, jars, jewellery, hull planks and, for the first time, human remains. These helped answer a few more questions about the wreck. The inscriptions on the coins and radiocarbon dating of the planks confirmed that the ship met with an accident sometime in the first century BC. The vessel was probably a merchant’s, inferred scientists, carrying luxury items from the eastern Mediterranean to be sold to rich Romans.
The next expedition began in 2012, when Foley began conducting a series of dives around the island. Improvements in diving technology allowed a deeper and hence more complete survey of the area. Over the next few years, according to Marchant, who has been tracking research on the shipwreck since the 2000s, the team accomplished robotic mapping surveys and discovered more luxury items among the ruins. Most notably, this June they found the first example of an ancient weapon, described in ancient texts as the ‘war dolphin’.
However, the big break was yet to come for Foley. On August 31, the underwater investigators found a set of bones, buried under sand and shards of pottery, all evidently belonging to the same individual. This person was presumed to have been a victim of the shipwreck. Judging from the bone’s quality, the scientists guess that it was a young male crew member, though this is yet to be confirmed. Although Cousteau had already found human remains in the 1970s, the recent find is more significant because the bones were found to be in remarkable condition, considering the circumstances.
Moreover, among the pieces of skull found, the petrous bones were found to be intact. Petrous bones are located behind the ear at the base of the skull. To ancient-DNA experts like Hannes Schroeder from Denmark, whom Foley invited to examine the remains, petrous bones are of special interest. Being one of the densest bones in the body, they are known for being one of the best sources of DNA, especially when the sample is found in non-frigid climes.
All Schroeder needs to proceed with DNA extraction is an OK from Greek authorities. If DNA is found, sequencing and analysis will be done, the results of which will be very exciting. “Human remains have started to become a source of information that can tell us incredible things about the past. Even with a single individual, it gives us a potentially great insight into the crew. Where did they come from? Who were these people?” Schroeder told The Guardian.
Ancient DNA analysis is not new to us. In 2010, the complete genome of a man who lived in Greenland 4,000 years ago was sequenced from a sample of his hair. The analysis of the genome showed that there was a migration from Siberia to Greenland more than 5,500 years ago. Based on the sequence, scientists were also able to reconstruct his appearance and predict his hair colour. In March this year, a small portion of the DNA from 430,000-year-old bones found in the mountains of Spain were successfully sequenced. The results added insight to our knowledge of human evolution, particularly when modern humans diverged from the Neanderthals.
Finding DNA in the Antikythera bones will be extra-special because these bones have not been treated with preservatives or been in contact with for a long time. This means the risk of contamination is relatively less. An analysis could reveal physical characteristics of the victim, allowing experts to deduce which part of the world he, and thus the ship, might have come from. It will allow us a more reliable glimpse into the civilisation that was apparently technologically advanced enough to have developed the world’s first computer, so to speak.