Johannesburg – At a time when ancient man was evolving modern human traits a small-brained relative was living alongside them, and like them was possibly disposing of its dead.
Scientists on Tuesday morning revealed the age of man’s newest relative Homo naledi and its young age has come as a surprise to academia and could shake up our understanding of our origins.
Homo naledi was alive sometime between 335 and 236 000 years ago. This makes them possibly the first species of hominid to have lived alongside humans in Africa.
The team of scientists came to this date through using several different techniques.
“The dating of naledi was extremely challenging,” said Professor Paul Dirks of James Cook University who worked with labs around the world.
“Eventually, six independent dating methods allowed us to constrain the age of this population of Homo naledi to a period known as the late Middle Pleistocene.”
Homo naledi was revealed to the world in 2015, after a National Geographic-funded expedition exhumed several skeletons from the Rising Cave System, in the Cradle of Humankind, near Johannesburg.
How the skeletons got into the cave has remained a mystery, but another discovery announced on Tuesday morning could help solve this riddle.
The team, led by Professor Lee Berger of Wits University announced the discovery of a second chamber in the Rising Cave System that contained additional Homo naledi skeletons.
“The chamber, which we have named the Lesedi Chamber, is more than a hundred metres from the Dinaledi Chamber. It is almost as difficult to access, and also contains spectacular fossils of naledi, including a partial skeleton with a wonderfully complete skull,” said Associate Professor John Hawks, who is part of the team.
The discovery of the new chamber – which means light in Setswana – believes the team, adds more support for their controversial hypothesis that Homo naledi was disposing its dead in the cave.
“There is no carnivore damage there is nothing, it is a mirror situation to the other chamber. Do I think it adds tremendous strength to the idea that Homo naledi was deliberately going into these chambers to dispose of its dead – yes,” said Berger.
The idea that a creature with a brain the size of an orange was travelling tens of metres into a pitch black cave to dispose of its dead has been criticised.
Palaeanthropologist Professor Chris Stringer of the Natural History Museum in London, said this ritualistic behaviour would be too complex for an animal with such a small brain, and he said he would want a more comprehensive study of the cave system to rule out the possibility of other entrances.
Their research has been published on Tuesday in the journal eLife.
From the Lesedi chamber the team were able to excavate one of the most complete hominid skeletons ever discovered. The skeleton has been named Neo, which means gift in Sesotho. The well-preserved skull has enabled scientists to have a closer look at Homo naledi’s face. Hawks said they even found remains of tear ducts.
Neo will be on public display at Maropeng from May 25.
But with Homo naledi possibly living alongside man, the team feel it could have huge implications for archaeology.
“The new dating puts it on the landscape at a time from which we find lots of tools in Africa in the middle stone-age. One of the implications of the new dates is that it’s no longer automatically possible for us to assume that early homo sapiens that were making these tools,” said Dirks.
But archaeologists like Dr Curtis Marean of Arizona State University want to first see tools associated with Homo naledi before considering the influence they have had on archaeological sites.