Discovery a reminder that we are not quite so special after all
FOR the past 40,000 years Homo sapiens – better known as us – have been in a highly unusual position: we have been alone. During the two million years preceding that, members of the genus Homo had, as with most animals on the planet, walked the earth alongside close relatives.
These early humans had interacted with each other, fought with each other and, quite possibly, evolutionary ancestors, or it is just possible it coexisted with some of the more modern ones such as the Neanderthals, and even ourselves.
This is particularly intriguing, as the skeletons also have some more modern adaptations, with feet and hands in some ways similar to our own – but with a skull considerably smaller.
‘‘The foot is one of the most human-like aspects,’’ said Professor John Hawks, from the University of Wisconsin-Madison.
‘‘It’s very clear the legs and feet were made for long distance and made each other extinct.
So it is perhaps a quirk of recent history that has led to our belief in human exceptionalism.
The more we find out about our closest human relatives, however, the less clear it is how special we are.
Yesterday’s discovery seems to at least imply that there was a species in South Africa that must have been cognitively very different to us but one that still engaged in behaviour we considered uniquely effective walking.’’
He said the hand was also very human-like. ‘‘There is a thumb proportioned like a human thumb, with fingertips broad and made for gripping objects with a powerful grip – possibly for manipulating objects like tools. But there are also very curved finger bones – probably indicative of activities like climbing.’’
Dr William Harcourt-Smith, from the American Museum of Natural History, said the evidence from its bones show that whenever it lived in the evolutionary tree, behaviourally it human – the ritualistic treatment of its dead.
Equally importantly, the discovery shows just how little we know about the richness of the evolutionary family that came before us. There is no trace of Homo naledi anywhere else on the planet. If they had not filled, for whatever reason, a single chamber deep underground with their dead, we would know nothing about them.
Even so, if the chamber’s narrow entrance had closed during the past existed somewhere between humans and other apes. ‘‘Much of the time on the ground it would have been bipedal,’’ he said, ‘‘but it would have been comfortable in the trees if it needed to be.’’
Whether in the trees or on the ground, it is also likely it would have just been one of several human species, interacting, and possibly sharing culture and technology, in a place that was a crucible for the human family.
‘‘Whenever this hominid lived it would not have been alone,’’ said Dr Harcourt-Smith. ‘‘Other species were around at the same hundreds of thousands of years, or if the cavers had been just a little fatter, we would remain unaware.
It seems highly likely there are other species of Homo that we have not found and will never find. But that does not mean that they are completely lost to us – there is just a chance their influence can live on in other ways.
Recently, scientists have discovered that these separate species were not quite so separate as modern tastes might like. In time, but how they interacted we don’t know. It is fascinating to think about.’’
No mystery is more fascinating though than how the bones ended up in the cave in the first place. Inside, there were no signs of habitation, no bones of animals, and no evidence they died in a single catastrophe. Rather than dying as one group, perhaps because a group had got lost and were unable to return, they seemed to have been deposited over many years, even centuries.
This led the researchers to conclude that what they were particular, DNA analysis has found that while Neanderthals may be extinct, part of them survives. Modern Europeans derive between two and four per cent of their genome from Homo neanderthalensis, probably the last of our relatives to go extinct.
Clearly at some of their lonelier moments in the icy forests of prehistoric northern Europe, modern humans did not consider themselves to be quite such a species apart after all. seeing was a ritualised burial site, that for some reason the bodies were carried to the back of the cave in darkness or – even more intriguingly – using fire to light the way.
‘‘There is a saying that when you eliminate the impossible whatever remains, however improbable, must be the truth,’’ said Professor Lee Berger, the lead scientist on the project, the results of which are published in the journal eLife.
‘‘This is a tiny-brained hominid. It is a creature we would have never expected to have complex behaviours. These individuals came in one at a time over some period of a time. They did not wash in there, were not moved by water, were not eaten by some super predator that could fit through an 18 centimetre slot. They were not scavenged there, they did not live there.’’
Geologists confirmed that the chamber had not been exposed to the outside world at any point – it would have always required an improbable journey, even for a species smaller than us.
‘‘The route to get to this chamber was not easy. It was so not easy that no other medium or large vertebrate before, after or during this event could get in. This leads to the remarkable conclusion: we have just met a new species of human relative that deliberately disposed of its dead in a chamber. Until this moment in history we thought the idea of ritualised behaviours directed towards the dead – burial, secreting in chambers – was utterly unique to Homo sapiens.’’
Editorial