Harnessing fire is up there with language and an upright stance in terms of "important milestones in early human development". And if the findings from a recent excavation are verified, hominids may have been playing with fire for far longer than we previously suspected.
A team led by Francesco Berna, an archaeologist at Boston University, made the discovery in Wonderwerk Cave, located in the Northern Cape province of South Africa. The team found the ash of grass and leaves, as well as bone fragments at a depth of 30m — roughly one million years ago. Wonderwerk is one of the oldest known caves to have sheltered hominids. Archaeological evidence hints that the cave has been employed from as long as two million years ago.
The excavated area is located far enough back in the cave to be out of reach of lightning strikes and has tested negative for bat guano (which can spontaneously combust in sufficient quantities), "This left us with the conclusion that the fire had to have been created by hominins," says Berna. "The fire was only confirmed when the sediment was analysed at the microscopic level. It is possible that the reason we have not yet seen more evidence of early fire use is because we have not been using the appropriate methods," he continued.
Derna's findings were published today in Proceedings of the National Academy of Sciences, and while many archaeologists agree that the evidence does suggest that hominins did use fire in the cave one million years ago, there is still debate on whether or not the early people mastered the flame sufficiently to cook regularly.
"I think it likely that humans were using fire at this site, but I don't think that this means these hominins were regular fire users. For a claim like that to be made, we would need to see hearths and fire places, and we do not," says Wil Roebroeks, an archaeologist at Leiden University in the Netherlands. "If we were to discover many more fire sites at this time in history and find that natural cave fires look distinctly different, that would support an early-cooking hypothesis, but we are not there yet."
The very oldest suspected cook sites in human history are located at Swartkrans site in South Africa and the Gesher Benot Ya`aqov site in Israel, dating 1.5 million and 800,000 years, respectively. However, they are both in the open and could well have been caused naturally by lightning strikes. The current oldest known evidence of cooking is only 400,000 years old so if the Wonderwerk cave does turn out to be legit, it will more than double the record. [Nature]