It is often said the ability to make fire is one of the key skills that defines humans – it allowed our ancestors to cook food, keep warm and eventually become the most dominant species on the planet.
Recently, evidence has been found across Europe to suggest that Neanderthals were also skilled fire users but now we may have to add another species to the list. Researchers excavating a complex network of caves in South Africa say they have unearthed evidence that Homo naledi, an extinct species of hominid that lived 200,000 to 300,000 years ago, also used fire as a tool.
The finding was announced at a lecture given by National Geographic Explorer-at-Large Prof Lee Berger of the University of the Witwatersrand, Johannesburg at Carnegie Institution of Science in Washington on 1 December. It has not yet been peer-reviewed.
“We are fairly confident to formulate the hypothesis that this small-brained hominid, Homo naledi, that existed at the same time we believe Homo sapiens were sharing parts of Africa, was using fire for a variety of purposes,” he said.
The remains of Homo naledi was first discovered in 2013 by Berger and his team hundreds of metres into a claustrophobically tight network of passages known as the Rising Star Cave system near Johannesburg, South Africa.
Subsequent excavations have since unearthed fossils from more than a dozen individuals – both male and female, juvenile and adult – as well as evidence of ritualistic burial practices in which the remains of certain individuals appear to have been washed and deliberately placed in position.
Then, earlier this year, after entering the caves himself for the first time, Berger says he noticed evidence of soot on the surfaces of the walls.
“As I looked up and stared at the roof, I began to realise that the roof was not a pure calcium carbonate. The roof above my head was greyed above fresh flowstone. There were blackened areas across the wall. There were soot particles across the whole of the surface. The entire roof of the chamber where we have spent the last seven years working is burnt and blackened,” he said.
At the same time, expedition co-director Dr Keneiloe Molopyane, uncovered the remains of a small hearth containing burnt antelope bones flanked by the remains of a much larger hearth in a nearby cave.
Further investigation of the system then uncovered several other caves and passages with chunks of burnt wood and charred animal bones.
“Fire is not hard to find. It’s everywhere within this system,” said Berger. “Everywhere there’s a complex juncture, they built fire. Every adjacent cave system to the chambers where we believe they were disposing of the dead, they built fires and cooked animals. And in the chamber where we believe they were disposing of the dead, they built fire but didn’t cook animals. That’s extraordinary.”
And there may be to come. Following the conference Berger Tweeted: "So. I have a terrible, shameful admission. The fire. It's not the big discovery I've been tweeting about. There's a bigger one. Actually there are three bigger than fire coming. Sorry."
The team now plan to work on radiocarbon dating their finds to firm up the link between the hearths and the Homo Naledi fossils.
“This is the most extraordinary period of exploration and discovery, and it’s going to continue,” said Berger. “The next generation don’t have a fear of exploration. Technology is opening spaces and places none of us could’ve have ever thought.”
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