Ancient DNA rewrites the stories of people buried by volcanic eruption in Pompeii

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Ancient DNA has revealed surprises about the identities of some people who perished in the ancient Roman town of Pompeii after a volcanic eruption, overturning misconceptions about their genetic relationships, ancestry and sex.

When Mount Vesuvius erupted in AD 79, the volcano spewed hot, lethal gases and ash into the air, slowly killing most of the city’s population. Ash and volcanic rock called pumice then covered Pompeii and its residents, preserving scenes of the victims of the city’s destruction like an eerie time capsule.

Excavations first began to unearth the forgotten city in 1748, but it wasn’t until 1863 that archaeologist Giuseppe Fiorelli developed a method to make plaster casts of some of the Pompeii victims. The soft tissue of the bodies encased in ash had decomposed over time, so Fiorelli poured liquid chalk into some of the outlines left behind by the bodies to preserve the shapes of 104 people.

Narratives formed based on the positioning of some of the remains, including those of an adult wearing a bracelet who was holding a child and thought to be the child’s mother. Similarly, a group of bodies found together were suspected of being sisters.

Now, during modern efforts to restore some of the casts, researchers retrieved bone fragments from within the plaster and sequenced DNA from them, discovering that none of those assumptions were true.

The discoveries, published Thursday in a new study in the journal Current Biology, are upending researchers’ understanding of the population demographics in Pompeii as well as how bodies found together were connected to one another.

“The scientific data we provide do not always align with common assumptions,” said study coauthor David Reich, professor of genetics at Harvard Medical School and a professor of human evolutionary biology at Harvard University, in a statement. “These findings challenge traditional gender and familial assumptions.”

A window to the ancient past

Pompeii’s unique preservation of the tragic tableaux of its citizens’ final moments has provided archaeologists with a way to understand what life was like during the Roman Empire.

Located about 14 miles (22.5 kilometers) southeast of Naples in what’s now Italy’s Campania region, Pompeii was geographically ideal due to its port, according to the study. While the Greeks, Etruscans and Samnites attempted to conquer it, Pompeii became a Roman colony, the study authors noted. But Mount Vesuvius’ eruption wiped it and other nearby Roman settlements off the map.

The ash spewed by the volcano coated the bodies of people and animals and encased buildings, monuments, mosaics, frescoes, sculptures and other artifacts in Pompeii and other surrounding towns. Rainfall after the eruption caused the bodies to become cemented within the ash, and the hardened ash preserved outlines of everything it blanketed, according to the study.

When excavations began at the Pompeii site centuries later, archaeologists uncovered nearly 1,000 outlines of people, both isolated and grouped together, in houses, squares, streets, gardens and just outside the city walls.

In 2015, the Archaeological Park of Pompeii began efforts to restore 86 of the 104 casts originally made by Fiorelli. X-rays and CT scans showed that while none of the casts contained complete skeletons, bone fragments were within many of them. The scans also indicated that when archaeologists and restorers initially worked with the casts centuries ago, they manipulated them — enhancing and altering aspects of the body shapes, removing bones and inserting stabilizers such as metal rods.

The Archaeological Park of Pompeii invited the study team to research the bone fragments and teeth that were accessible due to earlier damage to the casts, said coauthor David Caramelli, director of the department of biology and professor of anthropology at the University of Florence in Italy. The study team included the archaeological park’s past director, Massimo Osanna, current director Gabriel Zuchtriegel and park anthropologist Dr. Valeria Amoretti.

Together, park scientists and the study authors are working on a larger project to better understand the genetic diversity present in Pompeii during the Roman Empire.

“It is a ‘genetic’ photo taken of a Roman city from 2000 years ago,” Caramelli said by email.

Changing old assumptions

Some bones were mixed directly in with plaster used in the casts and incredibly fragile, but the team was able to extract and analyze DNA from multiple fragments.

The remains studied had been found at different sites preserved within the archaeological park, including the House of the Golden Bracelet, the House of the Cryptoporticus and the Villa of the Mysteries.

The House of the Golden Bracelet, a terraced structure decorated with colorful frescoes, was named for an adult found wearing the item and with a child astride on their hip. Next to them was another adult, presumed to be the child’s father. All three were found at the foot of a staircase that led out to a garden, while a second child was discovered a few meters away, possibly separated from the rest as they tried to escape to the garden.

It is believed the two adults and one of the children were killed when the staircase collapsed as they tried to flee, presumably to the nearby port.

Traditionally, researchers assumed the bracelet-wearing person to be the child’s mother. But the genetic analysis revealed the pair to be an unrelated adult male and child, Reich said. The adult male likely had black hair and dark skin.

The new study reveals a lot about our own cultural expectations, said Steven Tuck, professor of history and classics at Miami University in Ohio. Tuck was not involved in the new study.

“We expect a woman to be comforting and maternal, so much so that we assume a comforting figure is a woman and mother, which here is not the case,” Tuck said.

Learning more about the remains of people at Pompeii can help others appreciate those who lost their lives in the disaster, said Caitie Barrett, an associate professor in the department of classics at Cornell University. Barrett also was not involved in the new study.

“Whatever their relationship was, this is someone who died trying to protect the child, and who provided that child with their last moments of human comfort,” she said.

The House of the Cryptoporticus was named for the home’s underground passageway with openings that ran along three sides of the property’s garden. The home’s walls were decorated with scenes inspired by Homer’s “The Iliad.” While nine people were found in the garden in front of the home, casts could only be made for four of them.

Two bodies appeared to be embracing, leading archaeologists to hypothesize that they were two sisters, a mother and daughter, or lovers.

The new analysis showed that one individual was 14 to 19 years old at the time of death, while the other was a young adult. While sex estimation wasn’t possible for one of them, the other was genetically classified as a male.

The Villa of the Mysteries gets its name from a series of frescoes, dating back to the first century BC, that depict a ritual dedicated to Bacchus, the god of wine, fertility and religious ecstasy, according to the study authors. The villa included its own winepress, common for wealthy families at the time.

Multiple people were found in the house, and it was clear they died during different points of the eruption. The bodies of two adults, thought to be women, and a child were discovered where they fell on the home’s lower floor, while six more sets of remains ended up in overlaying ash deposits in the same home, suggesting they survived the first wave of the eruption, only to die later.

One person was found alone in a room with a whip and five bronze coins and wore an engraved iron ring bearing a female figurine. The man was thin and about 6 feet (1.85 meters) tall, and based on the traces of his clothes, he was likely the villa’s custodian who remained at his post until the end, the researchers said.

A cosmopolitan center

The genetic data collected during the research revealed that Pompeii was a cosmopolitan city full of people with diverse backgrounds, the study authors said.

Many descended from recent immigrants to Pompeii from the eastern Mediterranean, which reflects broader patterns of mobility and cultural exchange in the Roman Empire, said study coauthor Alissa Mittnik, group leader in the department of archaeogenetics at Germany’s Max Planck Institute for Evolutionary Anthropology and an associate in Reich’s lab at Harvard.

At the time, the Roman Empire extended from Britain to North Africa and the Middle East, while Pompeii was located next to one of the ancient world’s busiest ports, where ships regularly arrived from Alexandria in Egypt, Barrett said.

“What’s more, this part of southern Italy had an even longer history of international connections — the first Greek settlements in the Bay of Naples go back more than 800 years before the eruption of (Mount) Vesuvius,” Barrett said by email. “So it makes sense that the background and appearance of the population would have reflected this cosmopolitan history.”

The study is a great reminder of the nature of the Roman definition of family, which included everyone in the household and not just immediate members, Tuck said.

“The ethnic makeup of the deceased with so many markers from the eastern Mediterranean reminds us to be aware of the common Roman practice of enslavement and regular manumission (release from slavery) of foreigners,” Tuck said. “We know of that from Pompeii and can trace some of these people from their names in the later years of the city, but the stories told or assumed about these bodies assume a family of blood, not of slavery, marriage, manumission, adoption, and all the other ways families were created in the Roman world of Pompeii.”

Understanding the genetic diversity present in Pompeii reframes how scientists understand the city and its inhabitants, said Dr. Michael Anderson, chair of the department of classics and professor of classical archaeology at San Francisco State University. Anderson was not involved in the new study.

“It helps to topple the European ‘ownership’ of the so-called ‘Classical world,’ and showcases the degree to which those are misconceptions fabricated in the 18th and 19th centuries of our own time, that do not reflect the ancient reality,” Anderson wrote in an email. “Much of the modern interest in Pompeii has been driven by a desire to explore dramatic stories of death and destruction, to see ourselves reflected in the past, and is therefore a creation of a particular present, especially that of the time of original discovery. It is fantastic to see these old misconceptions definitively unraveled, and replaced with a much more diverse, interesting, and scientific reality.”

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