The revelation this week that a new species of extinct human – H. naledi – has been found in South Africa begs a whole lot of questions.
For me, it also reinforces the responsibilities we have today as humans. It’s like this. Some 737 bones totalling 15 near-complete skeletons were found in what seems to be a paleolithic graveyard. The interesting thing is their apparent intellect. There is evidence that they had spiritualism, because they seem to have had cultural mechanisms – involving massive effort – to dispose of their dead. The way they did it – carrying their dead deep into a hard-to-enter cave complex – also implies they had full control of fire, for light.
All of which is another question mark over the conceit that the things modern humans use to define ourselves are unique to us. That includes recursive logic, speech, abstract belief (religion/spiritualism), storytelling and creative thinking, all of which are meant to be consequential on our larger brain and reflecting some sort of innate superiority as a species.
But maybe they’re not. It could be we’re simply doing stuff that all human species (as in, genus Homo) did in their own ways. Perhaps the ‘ascent of man’ – often defined as things we do that animals don’t – happened in the Pliocene. Maybe all we’ve done since is a sideways skid. And that’s apart from broader behaviours we already know we share with apes, including a capacity to deceive, which demands substantial intellect, as we define it.
I can attest to that shared ape mind-set on personal experience; there was the time I had a meal with an orang-utan. They look like us, and that’s how they got their name. Orang hutan is Indonesian for ‘Forest Man’. Strictly speaking, they are well distant on the ape family tree. But there was no doubt to me that the orang-utan was just as self-aware as I was, shared the same basic body-language, and knew exactly what he was doing. He also selected healthier food than me, but hey… OK, things are a lot more sophisticated than my brief observations. But it highlights the point.
It’s taken a while to get to that thinking, though that’s not surprising. Nineteenth and twentieth century ‘progressivism’ portrayed our evolution as an ‘ascent’ up the brain-power ladder, which was defined by equating ‘intelligence’ with ‘ability to build Europe’s industrial technology’, and with a number (‘IQ’) obtained by arbitrary culture-centric testing. Everything else was ‘primitive’, ‘less evolved’, and couldn’t do what we did.
Evidence ranging from the discovery of Neandertal musical instruments and artificial epoxy resins (which they invented and manufactured) to burial sites for H. heidelbergensis suggests that, actually, our self-attributed ‘uniqueness’ was just a conceit. The fact that our cousin species hadn’t invented Gatling guns and middle-class gentlemans’ clubs didn’t mean they they were so dull-witted that they couldn’t.
But the mythology has taken a long time to shed. The idea of H. sapiens exceptionalism held sway as recently as the 1980s, when I was studying human evolution as part of my undergrad degree in anthropology.
In many ways this was understandable. Back in the 1980s, self-exceptionalism was dying a very, very slow death. With the exception of Neandertals, human evolution was known only through a small number of remains, hardly any of which had produced a whole skeleton (‘Lucy’ and ‘Turkana Boy’ were the exceptions, and even they were incomplete). This was fertile ground for open warfare between academics.
More crucially, there was also the fact that Earth today has but one species of human – us.
That point had been well known since the nineteenth century, and from that perspective it seemed axiomatic that there had only ever been one species of human at any time (except for Neandertals) – that each had evolved into the next (except Neandertals) at the expense of the old. This need to rationalise discoveries to ‘one type at any one time’ drove the main human evolutionary model of the 1980s, which was that humans (by a mechanism unknown to the rest of biology) simultaneously evolved into totally identical forms in widely dispersed parts of the world – the ‘multi-regional’ hypothesis.
To a large part the theory was an attempt to account for the fact that both older and modern human types had been found in places like Java, but where evidence for multiple ‘waves’ out of Africa hadn’t been found. Of course those multiple waves have since been identified – totally demolishing multi-regionalism. We’ve also sequenced the Neandertal genome – identifying the evolutionary reality of that species relative to us – and now have evidence to show that much of what we supposed was unique to modern humans was possible for other human types.
We now know:
- Just one species of human exists today, but that’s new – H. sapiens appears to be a lone survivor of a late-Pliestocene diaspora in which four closely related types (H. sapiens, H. neanderthalis, Denisovans and Red Deer Cave people) co-existed alongside more distant cousins such as H. florienisis (the ‘Hobbits’).
- Other human species weren’t automatically doomed at the hands of ‘superior’ H. sapiens. They did the same things we do. It seems that what counted wasn’t cranial capacity, but the way it was organised.
- Anatomically, humans have been virtually the same from the neck down since H. erectus appeared 1.5 million years ago. Their brain-size was at the lower end of the modern average range. It turns out there isn’t any automatic imperative in genus Homo to expand brain size. However, H. erectus cooked their food – meaning jaw muscles didn’t have to be so powerful. And they were tool makers, which became a mechanism in which the circuitry responsible for co-ordination (particularly) and planning was selected for. Both factors expanded brain size, but how that influenced intelligence is less clear.
- Each species of human didn’t automatically supplant the others, any more than lions supplanted tigers or bonobos supplanted chimps. Humans were subject to environmental-change pressures just like every species, and in the end all species of humans except ours died out. However, until recent times (meaning, up to about 50-20,000 years ago) a number of different types existed, not just H. sapiens’ immediate cousins but also more distant relatives such as H. floresiensis.
So it turns out that modern humans aren’t exceptional in the ways we imagined. And it also seems clear we didn’t survive because of some kind of ‘natural’ superiority. It increasingly looks as if our survival when the global climate went bad was more luck than anything else. In fact we came very, very close to going out totally about 70,000 years ago – that’s why every human alive today is VERY closely related, genetically. All. No exception. If we were dogs, we’d be a single breed. All of us. There’s a genetic marker carried by all humans outside Africa that makes clear that all are descended from a very small migratory population. Diversity within Africa is slightly larger, but not in any meaningful way. The original stock, we think, are the Kho’san – Nelson Mandela’s people.
The reality, then, is that we are all humans together – and not just all humans together, but the last humans.
The obvious question is what we are going to do with that responsibility. We’ve always supposed we’re exceptional. It seems that we’re not.
Instead, we’re the last survivors of a whole genus – Homo – who did something that no other creature on Earth ever did. Which is to be smart. And so we carry a tremendous responsibility.
Is there something we can do to preserve that – as the last carriers of that torch? Something that will make us exceptional? Meaning – can we overcome the limits of our human nature – the limits that are driving us towards damaging our environment past the point where it will support us. The limits that make us fight each other for reasons that, in hindsight, seem stupid. We have opportunity to change things. And the recipe isn’t difficult. All we have to do is think, reason and be reasonable, be tolerant, and to understand each other not as threats but as fellow humans – and move forward together.
Like all humans, we’re smart. We have the capacity if we want. I hope we will make the effort.
Copyright © Matthew Wright 2015