A 5,000-year-old cow tooth has yielded new evidence linking Stonehenge to Wales and shedding light on how the ancient monument’s huge stones could have been moved across Britain.

Stonehenge is one of the most famous monuments in the world. Credit: John Nail

The finding comes from a Neolithic cow jawbone that was discovered in 1924 beside the south entrance of Stonehenge. The bone had gone unremarked for many years until it was recently studied again by archaeologists from University College London (UCL), Cardiff University, and the British Geological Survey. Their study, published in the Journal of Archaeological Science, reports that the animal lived between 2995 and 2900 BCE—when construction on Stonehenge first started—and likely originated in Wales, the same region where the bluestones used to build the monument were quarried.

Researchers sliced one of the cow’s molars into nine thin sections using isotope analysis. Each slice preserved chemical traces from the diet and environment of the cow in its second year of life. The oxygen isotopes showed that the tooth formed from winter to summer over a period of six months. Carbon showed that in winter, it was consuming woodland vegetation, while in summer it consumed open pasture. Strontium isotopes, however, indicated that the seasonal foods had come from different geological areas, and therefore, the cow must have migrated or received imported fodder.

Most informative were the lead isotopes. These displayed an abrupt spike in late winter and spring, pointing to a source from much older Paleozoic rocks—the same type found in the Preseli Hills of Pembrokeshire, Wales, from which Stonehenge’s bluestones originated. This connection supports speculation that cattle may have been employed to help pull the mᴀssive stones onto Salisbury Plain.

The Altar Stone at Stonehenge located on Salisbury Plain. Credit: Pam Brophy / Past the Stones: Stonehenge / CC BY-SA 2.0

UCL Professor of Archaeology Michael Parker Pearson emphasized the significance of the discovery: “This is yet more fascinating evidence for Stonehenge’s link with south-west Wales, where its bluestones come from. It raises the tantalizing possibility that cattle helped to haul the stones.”

The team also found evidence that the animal was female and pregnant or nursing when its tooth developed. This was concluded from lead signals in the tooth, confirmed using a peptide-based Sєx test at the University of Manchester.

Stonehenge, a prehistoric monument in Wiltshire, England. Credit: Hulki Okan Tabak

To archaeologists, the positioning of the jawbone with so much care at Stonehenge’s entrance hints at symbolic meaning beyond its functional role.

British Geological Survey professor Jane Evans said, “A slice of one cow tooth has told us an extraordinary tale and, as new scientific tools emerge, we hope there is still more to learn from her long journey.”

Stonehenge, which stands on Salisbury Plain in Wiltshire, is one of the most famous monuments in the world. It was built over a period beginning around 3000 BCE and continuing for over a thousand years, with the last modifications occurring during the early Bronze Age. What the monument was used for—anything from celebratory rituals to astronomical alignments—is still debated, but the discovery of the Welsh cow tooth adds another piece to the puzzle of why and how this enduring prehistoric monument was built.

More information: Evans, J., Madgwick, R., Pashley, V., Wagner, D., Savickaite, K., Buckley, M., & Pearson, M. P. (2025). Sequential multi-isotope sampling through a Bos taurus tooth from Stonehenge, to ᴀssess comparative sources and incorporation times of strontium and lead. Journal of Archaeological Science, 180(106269), 106269. doi:10.1016/j.jas.2025.106269