DNA evidence rewrites story of people buried in Pompeii eruption

In 79 AD, Mount Vesuvius experienced one of its most significant eruptions, burying the Roman city of Pompeii and its inhabitants under a thick layer of small stones and ash known as lapilli. Many of Pompeii's inhabitants lost their lives as their homes collapsed under the weight of the lapilli raining down from many kilometres above. Those who survived the initial phase of the eruption eventually succumbed to the dangerous pyroclastic flows. This fast-moving stream of hot gas and volcanic matter instantly enveloped their bodies in a solid layer of ash, effectively preserving their bodies, including their features.

Since the 1800s, casts had been made by pouring plaster into the voids left by these bodies after their decay. The research team extracted DNA from the heavily fragmented skeletal remains embedded in 14 of the 86 famous casts undergoing restoration. This extraction process allowed them to accurately establish genetic relationships, determine sex and trace ancestry. Interestingly, their findings largely contradicted previous assumptions based solely on physical appearance and the positioning of the casts.

Genetic relationships of victims revisited

"This research shows how genetic analysis can significantly add to the stories constructed from archaeological data," says Professor David Caramelli, from the Department of Anthropology at the University of Florence. "The findings challenge enduring notions such as the association of jewellery with femininity or the interpretation of physical proximity as evidence of familial relationships." "Moreover," Caramelli adds, "the genetic evidence adds a layer of complexity to simple kinship narratives. For example, in the House of the Golden Bracelet, the only site where we have genetic information from multiple individuals, the four people traditionally thought to be the two parents and their children actually have no genetic ties to each other."

"The scientific data we provide do not always align with common assumptions," says David Reich of Harvard University. "For instance, one notable example is the discovery that an adult wearing a golden bracelet and holding a child, traditionally interpreted as a mother and child, were an unrelated adult male and child. Similarly, a pair of individuals thought to be sisters, or mother and daughter, were found to include at least one genetic male. These findings challenge traditional gender and familial assumptions."

Cosmopolitan nature of the Roman Empire

The genetic data also provided information about the ancestry of the Pompeians, who had different genomic backgrounds. The finding that they were mainly descended from recent immigrants from the eastern Mediterranean highlights the cosmopolitan nature of the Roman Empire.

"Our findings have significant implications for the interpretation of archaeological data and the understanding of ancient societies," says Alissa Mittnik of the Max Planck Institute for Evolutionary Anthropology. "They highlight the importance of integrating genetic data with archaeological and historical information to avoid misinterpretations based on modern assumptions. This study also underscores the diverse and cosmopolitan nature of Pompeii's population, reflecting broader patterns of mobility and cultural exchange in the Roman Empire."

"It is also likely that the use of these casts for narration purposes could have led to past restorers modifying their postures and placements," adds David Caramelli. "The combined use of genetic data and other bioarchaeological methods provides us with the chance to better comprehend the lives and habits of the victims of the Vesuvius eruption."

Gabriel Zuchtriegel, Director of the Pompeii Park, says, "The Pompeii Park has been including ancient DNA analysis in its study protocols for years, not only for human victims, but also for animal victims." He explains that the Park manages a variety of research projects through its own laboratory. These include isotopic analysis, diagnostics, geology, volcanology and, in particular, reverse engineering. He stresses that "all these elements together contribute to a comprehensive, updated interpretation of the archaeological findings. These efforts are turning Pompeii into a veritable incubator for the development of new methods, resources and scientific comparisons." Zuchtriegel concludes: "From this point of view, this study marks a true change in perspective, in which the site itself plays a central role in advancing archaeology and research."