New research shows they shared many behaviors that we long believed to be uniquely human. Why did science get them so wrong?
Joachim Neander was a 17th-century Calvinist theologian who often hiked through a valley outside Düsseldorf, Germany, writing hymns. Neander understood everything around him as a manifestation of the Lord’s will and work. There was no room in his worldview for randomness, only purpose and praise. “See how God this rolling globe/swathes with beauty as a robe,” one of his verses goes. “Forests, fields, and living things/each its Master’s glory sings.” He wrote dozens of hymns like this – awe-struck and simple-minded. Then he caught tuberculosis and died at 30.
Almost two centuries later, in the summer of 1856, workers quarrying limestone in that valley dug up an unusual skull. It was elongated and almost chinless, and the fossilized bones found alongside it were extra thick and fit together oddly. This was three years before Darwin published “The Origin of Species.” The science of human origins was not a science; the assumption was that our ancestors had always looked like us, all the way back to Adam. (Even distinguishing fossils from ordinary rock was beyond the grasp of many scientists. One popular method involved licking them; if the material had animal matter in it, it stuck to your tongue.) And so, as anomalous as these German bones seemed, most scholars had no trouble finding satisfying explanations. A leading theory held that this was the skeleton of a lost, bowlegged Cossack with rickets. The peculiar bony ridge over the man’s eyes was a result of the poor Cossack’s perpetually furrowing his brow in pain – because of the rickets.
One British geologist, William King, suspected something more radical. Instead of being the remains of an atypical human, they might have belonged to a typical member of an alternate humanity. In 1864, he published a paper introducing it as such – an extinct human species, the first ever discovered. King named this species after the valley where it was found, which itself had been named for the ecstatic poet who once wandered it. He called it Homo neanderthalensis: Neanderthal Man. Who was Neanderthal Man? King felt obligated to describe him. But with no established techniques for interpreting archaeological material like the skull, he fell back on racism and phrenology. He focused on the peculiarities of the Neanderthal’s skull, including the “enormously projecting brow.” No living humans had skeletal features remotely like these, but King was under the impression that the skulls of contemporary African and Australian aboriginals resembled the Neanderthals’ more than “ordinary” white-people skulls. So extrapolating from his low opinion of what he called these “savage” races, he explained that the Neanderthal’s skull alone was proof of its moral “darkness” and stupidity. “The thoughts and desires which once dwelt within it never soared beyond those of a brute,” he wrote. Other scientists piled on. So did the popular press. We knew almost nothing about Neanderthals, but already we assumed they were ogres and losers.
The genesis of this idea, the historian Paige Madison notes, largely comes down to flukes of “timing and luck.” While King was working, another British scientist, George Busk, had the same suspicions about the Neander skull. He had received a comparable one, too, from the tiny British territory of Gibraltar. The Gibraltar skull was dug up long before the Neander Valley specimen surfaced, but local hobbyists simply labeled it “human skull” and forgot about it for the next 16 years. Its brow ridge wasn’t as prominent as the Neander skull’s, and its features were less imposing; it was a woman’s skull, it turns out. Busk dashed off a quick report but stopped short of naming the new creature. He hoped to study additional fossils and learn more. Privately, he considered calling it Homo calpicus, or Gibraltar Man.
Neanderthals inhabited Gorham’s Cave on Gibraltar’s rough-hewed eastern coast on and off for 100,000 years, as well as a second cave next to it, called Vanguard Cave. The artifacts they left behind were buried as wind pushed sand into the cave. This created a high sloping dune, composed of hundreds of distinct layers of sand, each of which was once the surface of the dune, the floor of the cave. The dune is enormous. It reaches about two-thirds of the way up Gorham’s walls, spilling out of the cave’s mouth and onto the rocky beach, like a colossal cat’s tongue lapping at the Mediterranean. Every summer, since 1989, a team of archaeologists has returned to meticulously clear that sand away and recover the material inside. “I realized a long time ago, I won’t live to see the end of this project,” Finlayson, who leads the excavation, told me. “But I think we’re in a great moment. We’re beginning to understand these people after a century of putting them down as apelike brutes.”
Neanderthals are people, too – a separate, shorn-off branch of our family tree. We last shared an ancestor at some point between 500,000 and 750,000 years ago. Then our evolutionary trajectory split. We evolved in Africa, while the Neanderthals would live in Europe and Asia for 300,000 years. Or as little as 60,000 years. It depends whom you ask. What is clearer is that roughly 40,000 years ago, just as our own lineage expanded from Africa and took over Eurasia, the Neanderthals disappeared. Scientists have always assumed that the timing wasn’t coincidental. Maybe we used our superior intellects to outcompete the Neanderthals for resources; maybe we clubbed them all to death. Whatever the mechanism of this so-called replacement, it seemed to imply that our kind was somehow better than their kind. We’re still here, after all, and their path ended as soon as we crossed paths.
But Neanderthals weren’t the slow-witted louts we’ve imagined them to be – not just a bunch of Neanderthals. As a review of findings published last year put it, they were actually “very similar” to their contemporary Homo sapiens in Africa, in terms of “standard markers of modern cognitive and behavioral capacities.” We’ve always classified Neanderthals, technically, as human – part of the genus Homo. But it turns out they also did the stuff that, you know, makes us human.
Neanderthals buried their dead. They made jewelry and specialized tools. They made ocher and other pigments, perhaps to paint their faces or bodies – evidence of a “symbolically mediated worldview,” as archaeologists call it. Their tracheal anatomy suggests that they were capable of language and probably had high-pitched, raspy voices, like Julia Child. They manufactured glue from birch bark, which required heating the bark to at least 644 degrees Fahrenheit – a feat scientists find difficult to duplicate without a ceramic container. In Gibraltar, there’s evidence that Neanderthals extracted the feathers of certain birds – only dark feathers – possibly for aesthetic or ceremonial purposes. And while Neanderthals were once presumed to be crude scavengers, we now know they exploited the different terrains on which they lived. They took down dangerous game, including an extinct species of rhinoceros. Some ate seals and other marine mammals. Some ate shellfish. Some ate chamomile. (They had regional cuisines.) They used toothpicks.
Inside Gorham’s Cave, archaeologists were excavating what they called a hearth — not a physical fireplace but a spot in the sand where, around 50,000 years ago, Neanderthals lit a fire. Each summer, the Gibraltar Museum employs students from universities in England and Spain to work the dig, and now two young women – one from each country – sat cross-legged under work lights, clearing sand away with the edge of a trowel and a brush to leave a free-standing cube. A black band of charcoal ran through it.
The students worked scrupulously, watching for small animal bones or artifacts. They’d pulled out a butchered ibex mandible, a number of mollusk shells and pine-nut husks. They’d also found six chunks of fossilized hyena dung, as well as “débitage,” distinctive shards of flint left over when Neanderthals shattered larger pieces to make axes.
By that point, the enormousness of what they didn’t know – what they could never know – had become a distraction for me. One of the dig’s lead archaeologists, Richard Jennings of Liverpool John Moores University, listed the many items they had found around that hearth. “And this is literally just from two squares!” he said. (A “square,” in archaeology, is one meter by one meter; sites are divided into grids of squares.) Then Jennings waved wordlessly at the rest of the sand-filled cave. Look at the big picture, he was saying; imagine what else we’ll find! There was also Vanguard Cave next door, an even more promising site, because while Gorham’s had been partly excavated by less meticulous scientists in the 1940s and ’50s, Finlayson’s team was the first to touch Vanguard. Already they had uncovered a layer of perfectly preserved mud there. (“We suspect, if there’s a place where you’re going to find the first Neanderthal footprint, it will be here,” Finlayson said.) The “resolution” of the caves was incredible; the wind blew sand in so fast that it preserved short periods, faithfully, like entries in a diary. Finlayson has described it as “the longest and most detailed record of [Neanderthals’] way of life that is currently available.”
This was the good news. And yet there were more than 20 other nearby caves that the Gibraltar Neanderthals might have used, and they were now underwater, behind us. When sea levels rose around 20,000 years ago, the Mediterranean drowned them. It also drowned the wooded savanna between Gorham’s and the former coastline — where, presumably, the Neanderthals had spent an even larger share of their lives and left even more artifacts.
For decades, when evidence of a more advanced Neanderthal way of life turned up, it was often explained away, or mobbed by enough contrary or undermining interpretations that, over time, it never found real purchase. Some findings broke through more than others, however, like the discovery of what was essentially a small Neanderthal cemetery, in Shanidar Cave, in what is now Iraqi Kurdistan. There had been many compelling instances of Neanderthals’ burying their dead, but Shanidar was harder to ignore, especially after soil samples revealed the presence of huge amounts of pollen. This was interpreted as the remains of a funerary floral arrangement. An archaeologist at the center of this work, Ralph Solecki, published a book called “Shanidar: The First Flower People.” It was 1971 – the Age of Aquarius. Those flowers, he’d go on to write, proved that Neanderthals “had ‘soul.’ ”
As more supposed anomalies surfaced, they became harder to brush off. In 1996, the paleoanthropologist Jean-Jacques Hublin and others used CT scanning technology to re-examine a bone fragment found in a French cave decades earlier, alongside a raft of advanced tools and artifacts, associated with the so-called Châtelperronian industry, which archaeologists always presumed was the work of early modern humans. Now Hublin’s analysis identified the bone as belonging to a Neanderthal. But rather than reascribe the Châtelperronian industry to Neanderthals, Hublin chalked up his findings to “acculturation”: Surely the Neanderthals must have learned how to make this stuff by watching us.
A group at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, led by Svante Paabo, had been assembling a draft sequence of a Neanderthal genome, using DNA recovered from bones. Their findings were published in 2010. It had already become clear by then that Homo sapiens and Neanderthals appeared in Eurasia separately – “Out of Africa was essentially right” – but Paabo’s work revealed that before the Neanderthals disappeared, the two groups mated. Even today, 40,000 years after our gene pools stopped mixing, most living humans still carry Neanderthal DNA, making up roughly 1 to 2 percent of our total genomes. The data shows that we also apparently bred with other hominids, like the Denisovans, about which very little is known.
It was staggering; even Paabo couldn’t bring himself to believe it at first. But the results were the results, and they carried a sort of empirical magnetism that archaeological evidence lacks. “Geneticists are much more powerful, numerous and incomparably better funded than anyone else dealing with this stuff,” Zilhão said. He joked: “Their aura is kind of miraculous. It’s a bit like receiving the Ten Commandments from God.” Paabo’s work, and a continuing wave of genomic research, has provided clarity but also complexity, recasting our oppositional, zero-sum relationship into something more communal and collaborative – and perhaps not just on the genetic level. The extent of the interbreeding supported previous speculation, by a minority of paleoanthropologists, that there might have been cases of Neanderthals and modern humans living alongside each other, intermeshed, for centuries, and that generations of their offspring had found places in those communities, too. Then again, it’s also possible that some of the interbreeding was forced.
Paabo now recommends against imagining separate species of human evolution altogether: not an Us and a Them, but one enormous “metapopulation” composed of shifting clusters of essentially human-ish things that periodically coincided in time and space and, when they happened to bump into one another, occasionally had sex.
For millenniums, some scientists believe, before modern humans poured in from Africa, the climate in Europe was exceptionally unstable. The landscape kept flipping between temperate forest and cold, treeless steppe. The fauna that Neanderthals subsisted on kept migrating away, faster than they could. Though Neanderthals survived this turbulence, they were never able to build up their numbers. (Across all of Eurasia, at any point in history, says John Hawks, an anthropologist at the University of Wisconsin-Madison, “there probably weren’t enough of them to fill an N.F.L. stadium.”) With the demographics so skewed, Stringer went on, even the slightest modern human advantage would be amplified tremendously: a single innovation, something like sewing needles, might protect just enough babies from the elements to lower the infant mortality rate and allow modern humans to conclusively overtake the Neanderthals. And yet Stringer is careful not to conflate innovation with superior intelligence. Innovation, too, can be a function of population size. “We live in an age where information, where good ideas, spread like wildfire, and we build on them,” Stringer told me. “But it wasn’t like that 50,000 years ago.”
The Kennis brothers, Adrie and Alfons, are each 50 years old: identical twins. They are sturdy, attractive men, with dark, wildly swirling hair, and live in the small Dutch city of Arnhem, southeast of Amsterdam. When I arrived at Adrie’s house last summer, I found Alfons at the end of the driveway, glasses sliding down his nose, carefully filling a crack in the robin’s-egg-blue butt cheek of a silicon Neanderthal mold.
Kennis & Kennis had gradually co-opted Adrie’s house as a second studio. Most of their work and materials were here: full-scale headless bodies of various human species and a wall of shelves filled with skulls and heads. The heads were frighteningly realistic, with glass eyes and fleshy faces that begged to be touched. When the brothers fly around Europe to pitch to museums, they take these heads with them, like salesmen’s samples.
The more members your species has, the more likely one member will stumble on a useful new technology — and that, once stumbled upon, the innovation will spread; you need sufficient human tinder for those sparks of culture to catch.
“There was nothing inevitable about modern human success,” Stringer says. “It was luck.” We didn’t defeat the Neanderthals; we just swamped them. Trinkaus compares it to how European wildcats are currently disappearing, absorbed into much larger populations of house cats gone feral. It wasn’t a flattering analogy – we are the house cats – but that was Trinkaus’s point: “I think a lot of this is basically banal,” he says.
Jon Mooallem is a longtime contributing writer to The New York Times Magazine and the author of Wild Ones: A Sometimes Dismaying Weirdly Reassuring Story About Looking at People Looking at Animals in America, chosen a best book of 2013 by The New York Times Book Review, The New Yorker and Canada’s National Post. He also contributes to This American Life, Wired, California Sunday Magazine, is a writer-at-large for Pop-Up Magazine and has spoken at TED.