The earliest embers
Deep inside Wonderwerk Cave, a vast cavern that cuts 140 meters into the Kuruman Hills, lies evidence of fire use from one million years ago. Researchers found this evidence 30 meters from the cave entrance, a location too deep for a natural wildfire to have penetrated. The discovery consists of microscopic traces of wood ash, charred plant fragments, and burned animal bone fragments. These remains were found within a sediment layer known as Stratum 10, which is associated with the early Acheulean period.
Scientific analysis confirmed that these materials were heated to temperatures between 400 and 700 degrees Celsius, consistent with a small, controlled campfire. The analysis was conducted using micromorphology, which examines soils and sediments under a microscope, and Fourier-transform infrared microspectroscopy (FTIR), a technique that identifies the chemical composition of materials. The hominin species present in the region at this time was Homo erectus, an ancestor of modern humans. The evidence suggests they were carrying embers from natural fires into the cave and maintaining them.
A long history of habitation
The fire evidence is part of Wonderwerk Cave's long archaeological record. The cave's deposits are nearly 7 meters deep in some places and document almost two million years of environmental history and hominin activity. Excavations started in the 1940s and continue to yield information about the Stone Age.
The oldest layers contain simple Oldowan-type stone tools dated to around 1.8 million years ago. Overlying these are the Acheulean layers, which include early handaxes and the fire evidence from Stratum 10. The cave was used continuously through the Middle and Later Stone Ages. Much younger artifacts, including engraved stones from 10,500 years ago and rock paintings of animals, are found closer to the entrance. The geology of the cave itself is ancient; it is a solution cavity formed in dolomite rock that is over 2 billion years old and contains some of the earliest traces of life on Earth in the form of stromatolites. This long and layered history makes Wonderwerk Cave a site for understanding early human behavior.