Five thousand years ago, the people of Stonehenge buried cremated bodies under the ancient and mysterious site, near Amesbury, U.K. Archaeologists have long believed that the remains belonged to individuals connected with the monument, but for more than a century, they’ve been unable to figure out where they came from or why they were buried there. Now, a new analysis of these remains is providing some answers.
“This is an extremely important study,” says Martin Smith, a biological anthropologist at Bournemouth University in Poole, U.K., who was not involved in the research.
The burials of 58 individuals were uncovered in 1919. The cremated bones had been interred in now vanished organic containers, perhaps leather bags, in round pits near the monument. Intriguingly, these pits may once have held standing stones, as well as the human remains.
Dating of the remains later revealed that the cremations were interred during the earliest stages of the construction of Stonehenge, from 3000 to 2480 B.C.E. Experts still disagree on the purpose of Stonehenge; the prevailing hypothesis is that it was a temple connected with observing the movement of the sun. Others have argued it was a monument to the dead, where, as at nearby Durrington Walls, people from all over came together to feast.
Scientists do know that the builders brought some of the monument’s giant rocks, known as bluestones, from quarries in the Preseli Hills—a range of hills 220 kilometers away in western Wales. Researchers have also shown that people brought cattle to nearby Durrington Walls from all over, including Wales, though this site postdates the majority of the cremations at Stonehenge. These researchers didn’t have much or any human data, however.
Scientists have been unable to glean much information from the human remains because cremation destroys all organic matter, including DNA. In the new study, Christophe Snoeck, an archaeologist at the University of Oxford in the United Kingdom, decided to look at the levels of a form—or isotope—of the element strontium in the bones, which can reveal where the deceased had lived in the decade or so before death.
Strontium levels differ depending on local geology and other factors. From the soil, strontium enters plants. When those plants are eaten by animals and humans, it is incorporated into tissue and leaves its signature in bone. By comparing strontium levels recorded at different locations with those found in human remains, a person’s movements over the final decade of life can be revealed.
Normally, bones are unsuitable for this form of analysis, Snoeck says, because they absorb strontium from the soil “blurring the ‘biological’ signal.” But the high temperatures of cremation modified the structure of the bone, he says, effectively sealing in the strontium as it was at death. That such biological information survives the high temperatures of cremation was only recently discovered, Snoeck says.
The team studied 25 of the cremated individuals interred around Stonehenge. The strontium in their bones suggests at least 10 lived in western Britain, most probably west Wales, before death, rather than near Stonehenge, the researchers conclude today in Scientific Reports. The remaining 15 individuals appear to have lived exclusively in the region local to Stonehenge, at least in the last decade of their lives.
Another intriguing discovery: Using infrared and carbon isotope analysis of the bones, the researchers showed that the wood fuel used to cremate some of the bodies reflected that of dense woodland, as found in Wales, rather than the wood grown in the region of Stonehenge. This led them to argue that some individuals had been cremated away from Stonehenge and were brought to the site for burial.
“The analysis of the cremations suggests that communities in west Wales didn’t just supply the bluestones used to build Stonehenge, but were also allowed to be buried there,” says co-author John Pouncett, an archaeologist at Oxford. That suggests strong links between the two communities that trace back to the earliest days of the monument, he says.
Taken as a whole, the team’s findings highlight the movement of people, as well as materials, between these two regions. Previously, Smith says, some researchers suspected that people from the Preseli Hills had moved into the area of Stonehenge and appropriated the existing monument to make legitimate their claim to power and territory. “However, the current findings rather imply that the link between Stonehenge and west Wales not only stretched back to the earliest phases of monumental activity, but that this relationship was maintained over many centuries,” Smith says.
“As with all good studies the current project gives rise to further questions—it will be interesting to see where these lead next.”