Superior. Angela Saini

200,000 years, they didn’t always find the same evidence of symbolic thought and representational art. ‘The archaeologists came up with a way to square this,’ says Shea. ‘They said, well, okay, you know these ancient Africans, Asians, they look morphologically modern but they aren’t behaviourally modern. They’re not quite right yet.’ They decided that although such people looked like modern humans, for some reason they didn’t act like them.

      Rather than rethinking what it meant to be a modern human – perhaps taking out the requirement that Homo sapiens began making art immediately upon the emergence of our species – the rest of the world’s history became a puzzle to be solved. It’s a misstep that still has repercussions today. If art is what sets our species apart from Neanderthals and others, then at what point did we actually become our species? Was it 45,000 years ago when we see sophisticated cave art in Europe, or 100,000 years ago when, we now know, people used ochre for drawing? And if Neanderthals or other archaic humans turn out to show evidence of symbolic thought and to have made representational art, will we then have to call them modern too? ‘Behavioural modernity is a diagnosis,’ says Shea. All the archaeologists can think to do is ‘rummage around looking for other evidence that will confirm this diagnosis of modernity’.

      In the nineteenth century, such uncertainty around what constituted a modern human being was taken a leap further. If people weren’t cultivating the land or living in brick houses, some asked, could they be considered modern? And if they weren’t modern, were they even the same species?

      Australia in all its alien strangeness posed a particular challenge to European thinkers. Anderson and Perrin argue that the discovery of the continent helped shatter the Enlightenment belief in human unity. After all, here was a remote place, with its own animals not seen elsewhere, kangaroos and koalas, and with its own plants, flowers and unusual landscape. ‘Based on observations of the uniqueness of Australian flora and fauna’ there were ‘suspicions that the entire continent might have been the product of a separate creation,’ they write. The humans of Australia were thought to be as strange as everything else there.

      After the remains subsequently labelled Neanderthal were first identified in Germany’s Neander Valley in 1856, Martin Porr and his colleague Jacqueline Matthews have noted, one of the first things anybody did was compare them to indigenous Australians. Five years later, English biologist Thomas Huxley, a champion of the work of Charles Darwin, described the skulls of Australians as being ‘wonderfully near’ those of the ‘degraded type of the Neanderthal’. It was clear what they were insinuating. If any people on earth were going to have something in common with these now-extinct humans, European scientists assumed, it could only be the strange ones they called savages. Who else could it be but the people who were closest to nature, who had never fitted their definition of what a modern human was?

      *

      We are forever chasing our origins.

      When we can’t find what we want in the present, we go back, and back further still, until there at the dawn of time, we imagine we’ve found it. In the gloomy mists of the past, having squeezed ourselves back into the womb of humanity, we take a good look. Here it is, we say with satisfaction. Here is the root of our difference.

      Once upon a time, scientists were convinced that Aboriginal Australians were further down the evolutionary ladder than other humans, perhaps closer to Neanderthals. In 2010 it turned out that Europeans are actually likely to have the largest metaphorical drop of Neanderthal blood. In January 2014 an international team of leading archaeologists, geneticists and anthropologists confirmed that humans outside Africa had bred with Neanderthals. Those of European and Asian ancestry have a very small but tangible presence of this now-extinct human in our lineage, up to 4 per cent of our DNA. People in Asia and Australia also bear traces of another archaic human, the Denisovans. There is likely to have been breeding with other kinds of humans as well. Neanderthals and Denisovans, too, mated with each other. In the deep past, it seems, they were pretty indiscriminate in their sexual partnerships.

      ‘We’re more complex than we initially thought,’ explains John Shea. ‘We initially thought there was either a lot of interbreeding or no interbreeding, and the truth is between those goalposts somewhere.’

      The discovery had important consequences. It raked up a controversial, somewhat marginalised scientific theory that had been doing the rounds a few decades earlier. In April 1992 an article had been published in Scientific American magazine with the incendiary headline: ‘The Multiregional Evolution of Humans’. The authors were Alan Thorne, a celebrated Australian anthropologist, who died in 2012, and Milford Wolpoff, a cheery American anthropologist based at the University of Michigan, where he still works today. Their hypothesis suggested that there was something deeper to human difference, that perhaps we hadn’t come out of Africa as fully modern humans after all.

      Although this notion had been mooted before, for Wolpoff, his ideas became cemented in the seventies. ‘I travelled and I looked, I travelled and I looked, I travelled and I looked,’ he tells me. ‘And what I noticed was that in different regions, big regions – Europe, China, Australia, that is what I mean by regions, not small places – in different regions, it seemed to me there was a lot of similarity in fossils. They weren’t the same and they all were evolving.’

      Wolpoff’s big realisation came in 1981 when he was working with a fossilised skull from Indonesia – one of Australia’s closest neighbours, not far from its north coast – which was dated at roughly a million years and possibly older. A million years is an order of magnitude older than modern humans, hundreds of thousands of years before some of our ancestors first began to migrate out of Africa. It couldn’t possibly be the ancestor of any living person. Yet Wolpoff says he was struck by the similarities he thought he could see between its facial structure and that of modern-day Australians. ‘I had reconstructed a fossil that looked so much like a native Australian to me I almost dropped it,’ he says. ‘I propped it up on my lap with the face staring at me … when I turned it over on its side to get a good look at it, I was really surprised.’

      Teaming up with Alan Thorne, who had done related research and shared his interpretation of the past, they came up with the theory that Homo sapiens evolved not only in Africa, but that some of the earlier ancestors of our species spread out of Africa and then independently evolved into modern humans, before mixing and interbreeding with other human groups to create the one single species we recognise today. In their article for Scientific American, which helped catapult their multiregional hypothesis into the mainstream, they wrote, ‘some of the features that distinguish major human groups, such as Asians, Australian Aborigines and Europeans, evolved over a long period, roughly where these people are found today.’

      They described these populations as ‘types’, judiciously steering clear of the word ‘race’. ‘A race in biology is a subspecies,’ Wolpoff clarifies when I ask him about it. ‘It’s a part of a species that lives in its own geographic area, that has its own anatomy, its own morphology, and can integrate with other subspecies at the boundaries … There are no subspecies any more. There may have been subspecies in the past – that’s something we argue about. But we do know there are no subspecies now.’

      Many academics found Wolpoff and Thorne’s idea unconvincing or offensive, or both. According to historian Billy Griffiths, the multiregional way of thinking about our origins, undercutting the fundamental belief that we are all human and nothing else, has echoes of an earlier intellectual tradition that viewed ‘races’ as separate species. ‘Wherever we are in the world we look at the deep past and these immense spans of time through the lens of our present moment and our biases and what we want,’ he tells me. ‘Archaeology is a discipline that is saturated by colonialism, of course. It can’t entirely escape its colonial roots.’ Multiregionalism, while it was a response to the evidence available at the time, also carried echoes of the politics of colonialism and conquest. ‘That’s the ugly political legacy that dogs the multiregional hypothesis.’

      Wolpoff has always been sensitive to the controversy. He faced down plenty of criticism when he and Alan Thorne published their work. ‘We were the enemy,’ he recalls. ‘If we were right, there couldn’t be a single recent origin for humans