At a Glance
- New research provides a finite minimum age of 286,000 years for the scientifically important Petralona cranium found in Greece.
- Scientists applied U-series dating methods to the calcite mineral coating that had formed directly on the surface of the ancient skull.
- This age narrows a previously wide and debated estimate that had ranged from approximately 170,000 to 700,000 years old.
- The data also revealed that the calcite on the cranium is not from the same time as the cave wall where it was reportedly found.
- This timeline confirms the hominin was a contemporary of evolving Neanderthals, supporting a more complex model of human evolution in Europe.
Researchers have established a new minimum age for the famous Petralona cranium, a nearly complete human fossil discovered in a Greek cave in 1960 that has long puzzled scientists. Published in the Journal of Human Evolution, the study addresses long-standing questions about the age of the skull and its place in the human family tree. The fossil, belonging to the genus Homo, shows a unique mix of features, making it distinct from both modern humans and their close relatives, the Neanderthals, which has made placing it in our evolutionary history a significant challenge.
The team, led by the Institut de Paléontologie Humaine, employed a method known as U-series dating to analyze the thin layers of calcite that formed directly on the cranium. This technique relies on the natural radioactive decay of uranium isotopes into thorium at a predictable rate. As water seeps through a cave, it dissolves uranium and deposits it in mineral layers, or speleothems, without any initial thorium. By measuring the ratio of uranium to thorium in these layers, scientists can calculate a precise age for when the layer formed, effectively creating an atomic clock.
The analysis of the calcite crust on the fossil yielded a finite minimum age of 286,000 years, with a margin of error of 9,000 years. This result significantly narrows the previous age estimates, which ranged widely from 170,000 to 700,000 years old. Researchers also dated other mineral deposits in the cave, including those from the ‘Mausoleum’ chamber where the skull was reportedly found. These tests revealed the calcite on the cranium was not from the same time as the deposits on the cave wall, adding a new layer to the mystery of the fossil’s original location.
This revised timeline places the Petralona hominin firmly in the later Middle Pleistocene epoch. The findings support the idea that this distinct, more primitive human population coexisted in Europe alongside the evolving Neanderthal lineage. This paints a more complex picture of human evolution, suggesting multiple hominin groups lived in Europe at the same time, long before the arrival of Homo sapiens.
References
- Falguères, C., Shao, Q., Perrenoud, C., Stringer, C., Tombret, O., Garbé, L., & Darlas, A. (2025). New U-series dates on the Petralona cranium, a key fossil in European human evolution. Journal of Human Evolution, 206, 103732. https://doi.org/10.1016/j.jhevol.2025.103732
- Jackson, J. & Phys.org. (2025, August 20). Mystery Greek hominin skull dated to be at least 286,000 years old. Phys.Org; Phys.org. https://phys.org/news/2025-08-mystery-greek-hominin-skull-dated.html
