Last Ape Standing: The Seven-Million-Year Story of How and Why We Survived

by Chip Walter

  The artwork is nothing short of jaw–dropping, as beautiful and haunting as anything a modern artist could possibly conjure, and an indication that in these people, modern human behavior had irrevocably touched the world. Why the paintings were created is unknowable. They may have been religious, or a way to enter a spirit world, or simply the doodlings and artistry of generations of ancient but extraordinary humans who were expressing themselves in ways other humans never had. Hundreds of caves have now been discovered around the world filled with the imaginings of these and other ancient humans, all of them powerful illustrations of the playfulness and creativity, the childlike side of us, that distinguishes our species.

  As thoroughly as the archaeological record has been pored over, it has yielded nothing more than the skimpiest portrait of how the two species lived, let alone how they may have interacted. Homo sapiens, we know, had set up trading relationships with one another thousands of years earlier, which increased cooperation and improved their chances of survival. But because both species were itinerant, neither had yet established villages or cities, though there were settlements, favored places that clans and bands regularly returned to over long periods.

  Neanderthal and early Cro–Magnon existence may not have been terribly different from the way Native Americans lived on the plains of North America as recently as the nineteenth century—moving with the seasons, following the large animals they fed on, hunkering down in the winter against the elements, in and near caves that provided warmth and shelter, and then moving again when the weather grew a little kinder. Generation after generation they likely lived this way, bending with the climate, following the herds of mammoth, elk, and deer that provided them with food, clothing, bones for tools, many of the raw materials they relied on for their existence. Life was a short, harsh cycle of perhaps thirty to thirty–five winters and summers of close cooperation, family feuds, and occasional encounters with other humans, then death, at which time the next generation took on the fight. In some ways it isn’t all that different from our existence today. Life was shorter, it’s true, and tougher and the technologies different, but the same general pattern applied. They too sought love, enjoyment, and friendship and searched for ways to express themselves, just as we do. They were, after all, human as well. Just a different variety of human.

  All of this only makes it more tempting to wonder what happened during those long and wintry twenty-five millennia when our kind and Neanderthals coexisted. Why did Neanderthals fail to survive? It’s a vexing mystery. Every species runs its course. We know that. And the Neanderthal had made an immensely successful run. They roamed the steppes and mountain forests of Europe and western Asia through three ice ages, and their close cousin Homo heidelbergensis had survived a full two hundred thousand years before departing. During most of their time the Neanderthals were the dominant primate species north of Africa. But as the last glacial age began, ever so slightly, to wane, perhaps for the Neanderthal people their time for departure had simply come just as it had come for so many others before them. If that was the case, the arrival of modern humans couldn’t have helped their situation whatever the intentions of Homo sapiens. The Cro–Magnon were moving into the Neanderthals’ ecological niche and were proving to be better survivors.

  Some have speculated that we systematically wiped out our long–lost cousins as we came across them. When we met, the theory goes, if hunting or choice settlements and locations were at stake, the CroMagnon, with their superior weapons, and possibly their superior planning, killed or enslaved whoever got in their way, including Neanderthals. (They might have done the same to their own kind. We still do today.) It wouldn’t have been an all–out war in the sense that armies were assembled and clashed, but the damage done to the Neanderthals would have been relentless, with one settlement, tribe, or clan after another falling to the new intruders.

  There’s not much evidence for warfare or murder in the fossil record, however. We haven’t found ancient killing fields, strewn with the hacked and broken bones of the two species; no sites where dead Homo sapiens lie next to the skeletons of Neanderthals. The first evidence of a violent Neanderthal death was discovered in the Shandihar Cave in northeastern Iraq. The man was about forty years old when he met his end. Scientists found evidence of a wound from a spear, or some sort of sharp object, in his rib cage. Based on the nature of the wound, Steven Churchill, an anthropologist at Duke University, suspects a light spear thrown by a Cro–Magnon enemy inflicted it. It doesn’t seem to be the result of a thrust by a knife or a long Neanderthal spear, the kind they favored when hunting. It’s a theory, but a long way from a certainty. If this one man was murdered in this cave, or nearby where were the other victims? It’s just as likely that the man died from a wound suffered while hunting, or maybe another Neanderthal did him in.

  Other findings have been a little more conclusive, and considerably more gruesome. Paleontologist Fernando Ramirez Rozzi found something rare in the human fossil world, a cave called Les Rois in southwestern France that housed the bones of a modern human and a Neanderthal child lying together, positive proof that the two species came face–to–face. Unfortunately the jawbone of the child shows the same sort of markings paleontologists see on the bones of butchered reindeer skulls. The unappetizing conclusion is the child was made a meal of. Hints that other Neanderthals met a similar, cannibalized fate have been found at a site called Moula–Guercy near France’s Rhône River. Except in this case those who dined on their fellow humans were themselves Neanderthals. Perhaps it was a violent ritual, or the spoils of war, or maybe some who had died of starvation became the sustenance for those who survived. Not a cheery thought, but a world this harsh would inevitably require harsh choices.

  If there were violent meetings, then this is the extent of the evidence we have for now. Others if they exist have yet to reveal themselves. Maybe, somewhere in Europe, in a remote mountain forest or beneath a broad river rerouted by the last glaciers, lie the bones of prehistoric warriors who fell to the invaders from the southern seas. So far, though, no battlefields, and no warriors, have been found.

  A second theory that could explain the disappearance of the Neanderthals is that Cro–Magnon simply outcompeted them for resources, food, and land, not unlike the way we outcompete nearly every other species living wherever we show up. The thinking is that we didn’t kill them hand to hand, but we exterminated them in a war of attrition, by taking over the best habitats and hunting grounds, killing game faster than they could, and in larger numbers. Slowly, over thousands of years, the already sparse Neanderthal population retreated to pockets where it became increasingly difficult for them to survive. (We are doing this today to the gorillas and chimpanzees of Africa and the orangutans of Southeast Asia.) This might further have crippled Neanderthals’ ability to band together, weakening them still more, until in the end each of the dwindling clans died away.

  There is some evidence for this. Neanderthals did become progressively rarer as Europe withdrew into the coldest phase of the last ice age. Leslie Aiello of University College London suggests that Neanderthals, as adapted as they were to chilly climates, couldn’t survive temperatures below 0° F (−18° C). Their clothing and technology simply weren’t up to it thirty thousand years ago. As temperatures dropped and a new ice age descended, warm pockets of land would have become increasingly hard to find. If the Neanderthals retreated to them, they may have been trapped and died as even these locations grew too cold. Or they may have sought them only to find that the new creatures from the south had beat them to it, leaving them bereft of their favorite settlements and with no choice but to settle for places that, in the end, couldn’t sustain them.

  It might have happened this way. But Europe and Asia are immense territories, and it’s difficult to imagine that there wouldn’t have been enough resources to go around. The Neanderthal range covered tens of thousands of square miles. Genetic studies indicate the entire Neanderthal populations rarely numbered more t
han seventy thousand people spread from the Iberian Peninsula and the south of England clear to the plains of western Asia beyond the Caspian Sea. While each band probably needed several square miles of land to sustain them, much of the land was rich with food and resources and herds of large animals from mammoths and woolly hippopotamuses to deer, bison, and aurochs.f Even if the combined numbers of both Neanderthals and modern humans reached into the hundreds of thousands, there would seem to have been plenty of space, food, and resources, and much of Europe, even at the height of the last ice age, would have been temperate enough to accommodate any variety of human—Neanderthal or not. The frigid weather would certainly have battered Neanderthals trapped in cold areas, but why wouldn’t those already living in the more temperate climates of southern Italy, Spain, France, and the Mideast have survived?

  Maybe because it was more complicated than any one of these scenarios. Maybe the mysterious people from the south brought new diseases or parasites with them or forced radical cultural changes that Neanderthals simply couldn’t adjust to. After all, white men from Europe destroyed the cultures and ways of an entire continent of native North Americans, scores of individual tribes numbering in the hundreds of thousands, and they did it inside of four hundred years. This wasn’t simply a matter of brute slaughter. The blunt impact of a different kind of culture can also do considerable damage. Could immigrants from Africa have wreaked the same kind of havoc on the Neanderthal natives of Europe, except in this case taking twenty-five thousand rather than four hundred years? It’s possible.

  Stephen Kuhn and Mary Stiner at the University of Arizona suspect that modern humans arrived in Europe with cultures that divided labor within their tribes in a way that was safer for pregnant women, mothers, and children by keeping them focused mostly on collecting vegetables, fruits, and nuts, while men concentrated on hunting large animals. Based on their research, Kuhn and Stiner believe Neanderthals divided their labor among the sexes differently or, more accurately, didn’t divide it at all. Men and women both undertook the deadly work of bringing down big game, and that meant that women who were killed in hunts would not survive to bear more children. The teens and adolescents lost in hunts would further have depleted the clan.

  Though the Cro–Magnon approach to dividing labor didn’t mean they attacked Neanderthals, it would have had an impact nevertheless because eventually more Cro–Magnon women would have survived to bear more children than their Neanderthal counterparts, growing their population while Neanderthals struggled to keep pace with replacing the members they were losing. Even if the Neanderthal people were tougher, over thousands of years the competitive difference could have completely rearranged the population balance, just as divergent social approaches shifted the balance between whites and Native Americans.

  This may help explain why the Neanderthal population never really took off, even when ice ages relented. Their mortality rate was simply too high, and they were spread out too thinly. It may also help explain why their culture and technology remained doggedly unchanged for two hundred millennia. It’s terribly difficult, even within a clan, to pass along new ideas and innovations when members rarely lived past thirty or thirty–five years, and others are being wiped out in the prime of their childbearing years. Who knows how many Neanderthal Galileos or Einsteins died suddenly in the hunt and took their genius and inventions to the grave with them? It’s nearly impossible to build anything but the most rudimentary traditions when innovation is rare and life passes so quickly. In this scenario, the Neanderthal found themselves fighting, millennia after millennia, a pulverizing war of attrition. In the end, extinction was the only possible outcome.

  One last theory about the demise of Neanderthals is particularly tantalizing: If we killed them at all, we killed them with kindness. We neither murdered them nor outcompeted them. We mated with them and, in time, simply folded them into our species until they disappeared, reuniting the two branches of the human family that had parted ways in Africa two hundred and fifty thousand years earlier when small groups of restive Homo heidelbergensis headed across North Africa and into Europe.

  It’s fascinating to consider the possibility that we and another kind of human together bred a new version of the species. Whether this happened was, only a few years ago, one of the great controversies in paleoanthropology. But now there is persuasive evidence that something like it did.

  In 1952 the remains of an adult woman were found lying on the floor of the Pestera Muierii cave in Romania—a leg bone, a cranium, a shoulder blade, and a few other fragments. The people who discovered these bones didn’t think much of them. How old could they be, after all, if they were simply lying there on the ground for anyone to kick around? As a result, soon after their discovery they were squirreled away in a researcher’s drawer where for more than half a century they lay undisturbed and forgotten. Eventually, however, a team of scientists that included Erik Trinkaus at Washington University in the United States and two Romanian anthropologists, Andrei Soficaru and Adrian Dobos, rediscovered the bones and gave them a closer look, and when they did, they were stunned. Radiocarbon dating revealed the woman hadn’t lived recently at all, but last walked Earth thirty thousand years ago. The other startling discovery was that the fossils exhibited features that were clearly Cro–Magnon–like, but also distinctly Neanderthal. The back of the woman’s head, for example, protruded with an occipital bun, a distinct Neanderthal trait. Her chin was also larger and her brow more sloped than a modern human’s. The woman’s shoulder blade was narrow, not as broad as a modern human’s. Was she simply a rugged–looking modern human, or, as one scientist wryly put it, proof that moderns “were up to no good with Neanderthal women behind boulders on the tundra?”

  Other similar finds made recently throughout Europe keep boggling the minds of scientists who study this question. In another cave in France researchers have unearthed not bones, but tools that date back thirty–five thousand years. Their location indicates that for at least a full millennium both Cro–Magnon and Neanderthals coexisted in this place. If they could live together, and if they could communicate and cooperate, isn’t it likely that at least a few crossed the species line and, in a prehistoric foreshadowing of Romeo and Juliet, mated?

  Then there is the mysterious skeleton of a young boy unearthed in Portugal that is 24,500 years old. While conventional wisdom has it that the last Neanderthals died out thirty thousand years ago, the large size of this boy’s jaw and front teeth, his foreshortened legs, and broad chest have caused Trinkaus and others to wonder if he, too, might not be a hybrid. Though his chin is Neanderthal in size, it is also square, more like ours, and his lower arms were shorter and smaller than you might expect if he were Homo sapiens.

  Strangely enough, this part of Portugal is among the last places in Europe where Neanderthals lived before they disappear from the fossil record. Was this boy simply among the last of his kind, archaeological proof that Neanderthals were finally and inevitably swallowed, genetically or otherwise, into the rising tide of modern humans spreading across the planet?

  Until recently, the only evidences of interbreeding were perplexing finds like these, smoking guns that indicated we and Neanderthals had mated, but nothing irrefutable. Then in 2010 a scientific consortium headed by the Max Planck Institute for Evolutionary Anthropology completed its historic analysis of the Neanderthal genome, accomplishing for our burly cousin species what we had done for our ourselves seven years earlier. The analyzed DNA was extracted from three Neanderthal bones discovered at the Vindija Cave in Croatia not far from the Adriatic seacoast. To decipher the tantalizing possibility that we and Neanderthals may have produced common offspring in the deep past, the team compared the Neanderthal DNA with the genomes of five people of different lineages from around the world—French, Han Chinese, Papuans from New Guinea, and the Yoruba and San people of Africa. The San are, genetically, very close to the first modern humans to have evolved in Africa.

  What dumbfounded the
project’s investigators, and the rest of the scientific world, was that all the genetic samples taken, except for the Yoruba and San people of Africa, contained 1 to 4 percent Neanderthal DNA. In other words, most of the human race from Europe to the islands of Southeast Asia (and probably farther) is part Neanderthal! That Africans seem not to share any Neanderthal blood indicates that these two families mated after the wave of Homo sapiens departed Africa, but before their descendants headed into Europe and Asia. According to the researchers, this would have been somewhere between eighty thousand and fifty thousand years ago.

  Was that the only time modern humans and Neanderthals bred? The research team isn’t saying, but right now they can only base their conclusions on the research in hand. This will disappoint those who believe that Neanderthals and modern humans melded during those twenty-five thousand years of cohabitation in Europe into a single species whose recombined genes, shaped by separate evolutionary pressures, created a new kind of human. But it doesn’t rule the possibility out. There simply isn’t enough information on the scientific table right now to say.

  That we mated still doesn’t conclusively solve the mystery of how the hardy, quiet people of the North met their end. Was it murder, competition, or love? Does it have to be one or the other? Nature, evolution, and human relations are all chaotic and unpredictable, as much as we might like them otherwise. When Europeans colonized North and South America, they sometimes befriended the natives, sometimes brutally exterminated them, sometimes raped their women, and sometimes fell in love and raised families. Were Neanderthals so different from Cro–Magnon that sex was out of the question? If the Max Planck findings are accurate, clearly not. Both species were human, and the drive to procreate is strong and primal. Humans, after all, have been known to have sex with other primates, even other animals. Surely both species found enough common ground over twenty-five thousand years to bed down together during those frigid European winters. One of the inescapable lessons of evolution is, if anything can happen, it probably will.