Europe

by Tim Flannery

  It must be said of both the Neanderthals and the Tasmanians that their capacity to innovate persisted. In the early nineteenth century Tasmanian Aborigines adopted dogs and guns following contact with the Europeans. And there is some evidence that once the Neanderthals made contact with humans they borrowed ideas and ways of doing things, in doing so creating the Châtelperronian culture, which persisted until the moment of Neanderthal extinction.

  What to make of these most intriguing beings? We place such great emphasis on our own large brains in our claim to be Homo sapiens. Is it unreasonable to think that the Neanderthals may have exceeded us in some capacities? And what of their exquisitely made javelins, the equal of those that our best craftsmen can produce today, and of their ability to persist in the most extreme environments by hunting large, fierce prey? Imagine felling a woolly mammoth, or ousting a great hyena from its cave? I suspect that in some measures the Neanderthals were our superiors.

  But zoogeography was against them. Africa is larger than Europe, and its tropical climate and the fertile soils of the Great Rift Valley make parts of it highly productive. This means that populations of large mammals were usually greater and denser in parts of Africa than in Europe. Moreover, modern humans seem to have occupied a broader ecological niche than the hyper-carnivorous Neanderthals, eating vegetable matter processed by cooking, which allowed humans to sustain higher population densities than Neanderthals could.

  Competition between individuals in large, dense populations drives evolution faster. It produces more competitive types that can spread from their point of origin, displacing groups that dispersed earlier. This process can be aided by diseases, which also evolve swiftly in dense populations because transmission rates increase. Immunity builds in the dense population, but when isolated populations, not previously exposed to these diseases encounter them, they are likely to be devastated. This phenomenon of expansion from the centre is known as ‘centrifugal evolution’, referring to the way a centrifuge works to push things outwards; it goes a long way in explaining the demise of the Neanderthals.

  The final days of the Neanderthals have been extensively researched. Until recently, it was thought that they survived on Gibraltar until about 24,000 years ago, but all such late dates are now thought to have resulted from errors. A recent study, using more rigorous methods, could not find any valid dates for Neanderthals more recent than about 39,000 years ago. It is now thought that the Neanderthals began a rapid decline starting in eastern Europe around 41,000 years ago, and that they were extinct everywhere by 39,000 years ago.19

  It is widely believed that Neanderthals and humans overlapped briefly in Europe—for between 2500 and 5000 years. But I treat this with caution: the oldest dates for modern humans in Europe are highly questionable. The Neanderthals were the last species of Homo to share the planet with us modern humans. After they became extinct somewhere in Western Europe about 39,000 years ago, we were left alone. Our immediate family had been exterminated—almost certainly by our own hands. Yet this is, at best, a partial truth. Neanderthals did not die out, nor did modern humans colonise Europe.

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  * It is odd that Haeckel overlooked the very large Neanderthal brain, which was known from the original skull cap.

  * Their large eyes may have been adaptations to the low light conditions of the European winter, or to life in caves.

  CHAPTER 26

  Bastards

  The first anatomically modern humans (Homo sapiens) evolved in Africa around 300,000 years ago. By then, successive waves of upright apes, including Homo erectus and the ancestors of the Neanderthals, had been making their way into Europe from Africa for nearly two million years. Our species was destined to follow in their footsteps. By about 180,000 years ago Homo sapiens had pushed as far north as present-day Israel, where they may have hybridised with Neanderthals.1 But for reasons that remain unclear, these first African expatriates did not reach Europe. It was not until about 60,000 years ago, when humans again emerged out of Africa, that our species spread.

  A recent genetic study has established that the first human colonisers of Europe were a single population, derived in part from African migrants who arrived around 37,000 years ago, and who fell within the genetic variability of living Africans.2

  Dating the chronology of hominid invasions and extinctions can lead to confusion. This is in part because the events were dated using different methods (for example, genetic comparisons and radiocarbon dates). Dates based on genetic comparisons rely on rates of genetic change, which are ‘anchored’ by reference to the fossil record, while radiocarbon dates rely on estimates of decay of C14. All dates are estimates, often with wide margins of error, and all methods of dating have their own biases, which can introduce errors. We should keep in mind that it is entirely possible that the date of Neanderthal extinction (radiocarbon dated to about 39,000 years ago) and the date for human arrival (derived from genetic analysis as 37,000 years ago) in fact occurred in the same millennium.

  Among the oldest undisputed collection of human remains from Europe includes partial skeletons, skulls and jaws found in the Peştera cu Oase caves, near the Iron Gates on the Danube in Romania. The bones have been dated to between 37,000 and 42,000 years old, with a most likely age of 37,800 years.3 The caves lie on a migration route into western Europe known as the Danubian Corridor. First identified by the archaeologist Vere Gordon Childe, many species have doubtless followed the corridor over millions of years.

  The bones found in Peştera cu Oase were first identified as those of modern humans, but then it was noticed that they have some Neanderthal-like features. Ancient DNA recovered from one skeleton revealed that it was a human–Neanderthal hybrid, in whom large chunks of Neanderthal DNA (including almost all of chromosome 12) was interspersed with modern human DNA. With each generation, the DNA is mixed into ever smaller segments. The fact that the Neanderthal DNA occurred in such large pieces in the Peştera cu Oase individual indicates that the hybridisation event had occurred just four to six generations back.4 So, we know that about 38,000 years ago, somewhere near the Iron Gates, a human and a Neanderthal had sexual intercourse, and that the female successfully raised offspring, which was able to reproduce.

  These human–Neanderthal hybrids were probably just one of many hybrid groups that have occurred during hominin evolution. Evidence survives in our genes of at least one other recent event—that between Denisovans and humans who spread east into Asia.* But what of those first-generation European human–Neanderthal hybrids? What were they like? In his epic 1903 work The Dawn of European Civilization, Griffith Hartwell Jones, Rector of Nuffield, uses a variety of ancient sources to reconstruct a people whom he believed inhabited Europe prior to the advent of farming. He calls them Aryans, and describes the male as follows:

  His eye was blue and fierce…he had beetling eye-brows. He was tall of stature and endowed with a powerful frame. Nurtured in a cold climate, where Nature was rugged and inhospitable, he was inured to hardship from infancy…The chase, which was his natural pastime, kept him in constant practice in the use of weapons…5

  Written long before modern science had fleshed out our understanding of Neanderthals, it is as complete a portrait of a Neanderthal as one could want. Mix that with African genes, and the progeny would have been highly varied. Perhaps the great variation among living Europeans is an echo of the diversity seen among the first human–Neanderthal hybrids.**

  In 2010 researchers announced that the entire Neanderthal genome had been sequenced.6 No Neanderthal DNA has been found on any human Y-chromosome—the chromosome passed on only by males.7 Unless resulting from chance, this absence could mean one of two things. It’s possible that sex was only between human males and Neanderthal females; or it may result from a curious genetic phenomenon known as Haldane’s rule. Formulated by the great British evolutionary biologist J. B. S. Haldane in 1922, it states that where only one sex is sterile in a hybrid (such as in mules), it
is likely to be the sex with two different sex chromosomes. In humans (and most mammals) males have an X and a Y chromosome, and females two Xs, so Haldane’s rule predicts that in mammals, male hybrids are more likely to be sterile than female ones. One study hints at the possibility that Haldane’s rule may have been the cause of the lack of Neanderthal DNA on the Y-chromosome of hybrids, but currently we do not definitively know.8

  There are two main claims for fossilised human remains from Europe older than those from Peştera cu Oase. Two baby teeth, reportedly belonging to a modern human and dating to between 43,000 and 45,000 years old, were found in a cave south of Taranto in Italy, while a fragment of a human upper jaw, associated with animal bones dated to between 41,500 and 44,200 years old, comes from a Kentish cave.9 The baby teeth have been dated by extracting material from them, but they have yielded no DNA, which means that their identification as human is based on shape alone. The Kent mandible, on the other hand, is clearly human, but its age was inferred from dates taken from animal bones preserved in the same deposit. It remains a leap of faith to assume that the human and animal bones are indeed the same age. In both cases the evidence is, I think, too thin to establish an earlier human presence in Europe.

  As a palaeontologist, I am used to dealing with scraps of evidence, and resigned, courtesy of Signor-Lipps, to accepting that I’ll never find the first or the last member of any species. Can we really have been fortunate enough, at Peştera cu Oase, to have discovered evidence of one of the earliest generations of European pioneers? I cannot prove it, but the site seems special—special enough, indeed, to be the one possible exception to the dictum of Signor-Lipps in this entire ecological history.

  No Neanderthal bones were found at Peştera cu Oase; the hybrid’s bones appear to have been washed into the caverns from outside and no rubbish dumps indicating that people inhabited the caves have been found there. We will never know for sure what happened at the Iron Gates those tens of thousands of years ago. All we can do is paint a scenario consistent with our few facts: a group of humans, on their frontier trek into new European territory, encountered a group of Neanderthals whom they ambush, killing all except the women, who are abducted and bear their abductors’ children.

  But there must be more to the story than this. There is something strange about the lateness of the human colonisation of Europe. As modern humans spread, one branch followed the south Asian coast and by at least 45,000 years ago had reached Australia. Europe is much closer to Africa than Australia is—so why did it take humans so much longer to colonise Europe? Part of the answer may lie in the ecological niches occupied by the early human migrants. The bands that pushed on to Australia seem to have become adept at harvesting fish and shellfish—a niche that was previously largely vacant, but which offered abundant fat and protein. Using spears, nets, stone hammers and rafts, humans could exploit the enormous bounty that existed on nearshore reefs and mudflats in a way that no other species could.

  But humans living away from the coast had to compete for terrestrial resources with related species—either Neanderthals, Denisovans or Homo erectus—that were already adept at harvesting them. Moreover, 38,000 years ago Europe was a chilly and hostile place, in which a tropical hominid may have struggled to survive. The Neanderthals, already adapted over the millennia to Europe’s harsh conditions, may have been tough competition. But then a chance event created human–Neanderthal hybrids, who quickly spread west, displacing the ‘pure’ Neanderthal populations.10 It seems probable that the first human–Neanderthal hybrids possessed useful knowledge passed on by their Neanderthal mothers; and in Europe’s climate, the pale skin of the Neanderthals must have been particularly advantageous as it allowed sunlight to penetrate, aiding the creation of Vitamin D.

  A recent study of 50 fossils from across Europe reveals that all Europeans living between 37,000 and 14,000 years ago were descended from this founding population of human–Neanderthal hybrids. This indicates that non-hybrid humans did not make it into Europe until at most 14,000 years ago. Had scientists been around back then, they might have classified the Europeans as a new hybrid species, like the wisent. But over time, the proportion of Neanderthal DNA in the Europeans’ genome decreased. In Europeans living between 37,000 and 14,000 years ago, the Neanderthal genetic inheritance averaged about six per cent. Following a migration from southwestern Asia around 14,000 years ago, this contribution was diluted to between 1.5 and 2.1 per cent (today’s average). Researchers argue that many Neanderthal genes must have disadvantaged the hybrids that bore them. But just which genes, and how they acted against survival, is not clear.11 Intriguingly, however, at least 20 per cent (and perhaps 40 per cent) of the entire Neanderthal genome survives within the genes of the European and Asian populations, because individuals have different segments of the Neanderthal genome.12

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  * The Denisovans are an extinct species or subspecies of humans known only from a few teeth and a finger bone from Denisova Cave in Siberia. They hybridised with humans, and their genes are preserved in living Asian and Australasian human populations.

  ** The discovery that 10,000-year-old ‘Cheddar Man’ had blue eyes but dark skin is to be expected in this hybrid population.

  CHAPTER 27

  The Cultural Revolution

  In 1861 the French writer and artist Édouard Lartet published a drawing of a piece of bone, discovered in Chaffaud Cave in southern France, upon which the image of two hinds had been engraved. Lartet claimed that the engraving, along with other artefacts, dated from the earliest antiquity. At first his claim was met with great scepticism because European savants firmly believed that the brutish cave dwellers of the stone age were incapable of refined art. But as more pieces were discovered along with stone tools, Lartet’s argument became irrefutable. Then, in 1868, paintings were discovered on the walls of a cave near Altamira in Spain, and Europeans moved closer to understanding the extent of the treasure that their most distant ancestors had bequeathed them. As more and more Palaeolithic art was discovered, it became clear that the greatest artists of Europe’s stone age rivalled in vision and execution the most accomplished artists alive today.

  The earliest European ice-age art is among the most striking and ingenious. One example is a magnificent 40,000-year-old half-lion, half-human carving, made of mammoth ivory and found in 1939 in Hohlenstein-Stadel, a deep cave in the Swabian Jura in Germany. The site has yielded no evidence of domestic occupation such as food remains and tools—it may have been reserved for ritual activities. The lion-person was found in more than 250 fragments.1 Reconstructed, it stands 30 centimetres tall and has immense, almost magisterial, presence. The Swabian Jura also yielded the oldest figurative carving of a human—the Venus of Hohle Fels (Venus of Stone Hole)—which dates to between 35,000 and 40,000 years ago. Astonishingly, the world’s oldest musical instrument—an ivory flute—was excavated from the Jura. It is thought to be as much as 42,000 years old, but we must keep in mind the uncertainty around such dates: the flute may be roughly contemporaneous with the Peştera cu Oase bones. These creations are attributed to the Gravettian culture, whose makers were early human–Neanderthal hybrids.

  The Swabian Jura are on the Danubian Corridor, which was probably followed by the hybrid people that arose near the Iron Gates. I can imagine those pioneer beings, endowed with capacities not seen in either parent, pushing west and displacing the Neanderthals they encountered. As they settle new lands, they seek new means of expression. Neanderthal knowledge may have helped the hybrids occupy caves. In chilly Europe, caves were home for entire winters, with frozen meat and other food stored nearby. And living in caves created new imperatives and opportunities for storytelling and graphic depiction.

  The flowering of artistic expression suggested by the finds from the Swabian Jura is unique in human evolutionary history. The artefacts are the oldest evidence we have from anywhere on Earth for carvings of imaginary creatures and humans, and of musical instr
uments. Those responsible for this artistic flowering were hybrids who, like the mule, seem to have been possessed of great reason, memory and social affection, as well as creative spirit. I find it astonishing that their novel creations were works of art, rather than the new weapons or the stone tools characteristic of earlier advances. It’s as if these beings had begun a process of ‘auto-domestication’, with a focus on peaceful interactions rather than conflict.

  It is tempting to see the sculptures and flutes as the pinnacle of ice-age cultural achievement; but these objects served a purpose, and it is the higher art that they served that we must view as the pinnacle. There is reason to believe that the art was theatre: theatre is the great art of Aboriginal Australia, and arguably it was the premier art in all pre-literate societies. Theatre is so important to those societies because it promotes the skills of imitation, rhetoric, expression of emotion through the whole body, and storytelling that make great hunters and leaders. Thus Shakespeare did not spring fully formed—like Athene from Zeus’ head—but from a tradition that has existed at least since the creation of the first human–Neanderthal hybrids.