New analysis of material from Wonderwerk Cave in the Kalahari Desert, South Africa, has identified possible evidence of the earliest cave occupation in the world, as well as early human use of fire.
The site, which was first excavated in the 1940s, has a unique stratigraphic record containing evidence of human activity from the Early Stone Age to the present day. The new study, recently published in Quaternary Science Reviews, took samples of cave sediment containing botanical, faunal, and artefactual remains, and used palaeomagnetism to determine the age of the Oldowan stone tools in the cave. They found that the Oldowan tools dated to 1.8 million years ago, representing the earliest hominin occupation of a cave associated with this industry.
Evidence for fire was also found deep within Wonderwerk Cave, with deposits containing burnt stone, bone, sediment, and ash found in the Acheulean layer discovered around a decade ago. Archaeologists originally suggested that the fire dated to c.1 million years ago, but this date was questioned by critics. However, the new research has confirmed a date of at least 900,000 years ago using cosmogenic isotope dating, which measures the concentration of isotopes in sand particles to find out when they entered the cave. Examples of fire have been found at other early human sites, but these are all open-air locations where burning could have been the result of lightning strikes rather than deliberate human use. The discovery of fire in Wonderwerk Cave is significant because it is unquestionably associated with human activity. This clear indication that humans were using fire and thus probably had the ability to cook food at least as far back as 900,000 years ago, and potentially much earlier, could have a significant impact on our understanding of hominin evolution.