Bones Indicate Possible Fire Use By Human Ancestors 1.8 Million Years Ago

A team of researchers has discovered compelling evidence that early hominins, most likely *Homo erectus*, were using fire as early as 1.79 million years ago in South Africa’s Wonderwerk Cave. The findings, published in *PLOS One*, extend the known timeline for controlled fire use by hundreds of thousands of years and were uncovered by analyzing 161 tiny fossilized bones from small mammals in two layers of the cave: Stratum 10 and Stratum 11. The study employed a novel method called bone luminescence, alongside Fourier Transform Infrared Spectroscopy (FTIR), to detect signs of burning on the bones. Under high-energy blue light, bones exposed to high temperatures emitted a reddish glow, while unheated bones remained dark. The analysis revealed that every white and gray fossil bone tested in Stratum 11, dating between 1.07 and 1.79 million years ago, showed clear evidence of burning. The location of the burnt remains—at least 30 meters inside the cave entrance—rules out natural wildfires as the cause, strongly suggesting early hominins deliberately carried fire into the cave. The burnt bones were found in clusters, indicating repeated, intentional burning events over long periods. This discovery aligns with the presence of Acheulean stone tools, further linking the fires to hominin activity. While the study does not prove these early humans could create fire from scratch, it implies a sophisticated level of interaction with fire. The ability to control fire would have provided warmth, protection, and cooking benefits, potentially contributing to the evolutionary expansion of the human brain. Wonderwerk Cave has long been recognized as a critical site for studying early fire use, with previous research identifying traces of burning dating to around one million years ago. This new study, however, significantly extends that record by examining deeper, older deposits.