Hebrew University scientist's team finds signs of fire use up to 1.8 million years ago

An international team that includes Dr. Liora Kolska Horwitz of the Hebrew University of Jerusalem has reported evidence that early human ancestors were using fire inside South Africa's Wonderwerk Cave as long as about 1.8 million years ago. The study, published in June 2026 in the journal PLOS One, pushes the cave's record of fire use back by hundreds of thousands of years. The paper's first author is M. Dolores Marin-Monfort. Kolska Horwitz, of the university's National Natural History Collections, co-directs the Wonderwerk project with Prof. Michael Chazan of the University of Toronto, and the team included scientists from Israel, South Africa, Canada, Spain, Portugal, Argentina, the United States and Britain.

Wonderwerk, in the Kalahari region, is sometimes called the oldest known cave home: it preserves traces of human occupation going back nearly two million years, associated with simple Oldowan stone tools. Research published in 2012 had already found intentional fire use in a higher layer of the cave dated to about one million years ago. The new evidence comes from a deeper layer, separated by roughly 80 centimeters of sediment, that was occupied between about 1.79 and 1.07 million years ago, according to dates obtained from changes in Earth's magnetic field and from quartz grains in the sediment.

The breakthrough came from a new way of detecting burning. Bones exposed to intense heat glow distinctively under certain wavelengths of light, so the team could identify burned fragments without grinding them up, making the test cheaper, faster and usable in the field. The burned bones were found at least 30 meters from the cave entrance, which rules out a passing wildfire, and the layer contained nothing likely to ignite on its own.

Kolska Horwitz stressed that using fire is not the same as making it: early hominins, probably Homo erectus, may have carried in flames from natural fires rather than starting them. No human remains have yet been found at the site. The team planned further excavations in July 2026 to search for fire in the cave's oldest layer, roughly two million years old.