Passing the ‘chimp test’: how Neanderthals and women helped create language

12th September, 2021.      //   Market Intelligence  // 

A depiction of a neanderthal family in a cave.

How and when did human language evolve? Did a “grammar module” just pop into our ancestors’ brains one day thanks to a random change in our DNA? Or did language come from grooming, or tool use, or cooking meat with fire? These and other hypotheses exist, but there seems little way to rationally choose between them. It was all so very long ago, so any theory must be essentially speculation.

Or must it? This is the question presented as an elegant intellectual thriller by The Dawn of Language: Axes, Lies, Midwifery and How We Came to Talk. Its author is Sverker Johansson, a serene and amiable 60-year-old Swede who speaks to me over Zoom from his book-crammed home study in the city of Falun, where he works as a senior adviser at Dalarna University.

Johansson actually began his academic life as a particle physicist, but, he now explains: “I felt a growing frustration with that field, because it was becoming more and more industrialised. I felt like the guy on the Ford assembly line, screwing screw number 37 over and over and over again. That’s not what I want to do as a researcher.” He smiles. His first detour was into neutrino astronomy, and then he became fascinated by linguistics, and the puzzle of how language exists at all.

He began attending yearly conferences devoted to the question, and wrote an academic book, Origins of Language: Constraints on Hypotheses (2005). His new book, however, is not merely a popularisation of that one. For one thing, he says, he has changed his mind about the Neanderthals. Scientists have since sequenced the entire Neanderthal genome, and we now know that Neanderthals interbred with modern humans before dying out only about 30,000 years ago. This means, for Sverker, that they could almost certainly talk. “If two people have kids together,” he points out, “I very much doubt that one was without language and the other one with.”

In his book, indeed, he offers a rousing defence of the Neanderthals against decades of prejudice: “Even today the word ‘Neanderthal’ is used as a pejorative term for people with the kind of primitive attitudes we do not feel are appropriate for a Homo sapiens,” he writes. “It is both bigoted and sad that another kind of human should be devalued in this way simply because they were different […] The Neanderthals were Europe’s original inhabitants, the only true Europeans. We and the Neanderthals went our separate ways about half a million years ago. It was in Europe that they evolved from earlier forms of humans, whereas we Homo sapiens are relatively recent immigrants from Africa.”

A determination to redress unthinking prejudice is also behind the curious fact that Johansson is, on one possible estimation, the world’s most prolific author. In parallel to his studies in the origins of language, he also maintains a web-crawling bot (LSJbot) that scrapes geographical, meterological and other data and automatically creates short Wikipedia articles. “Wikipedia has excellent geographic coverage where young white males live,” he explains drily. “North America, Europe, generally industrialised countries – but Africa was basically a blank spot. Suppose there is a disaster in some village somewhere. What do you do as a journalist? You look the village up on Wikipedia, and if you have a stub [a short article] there, you can at least see which province it is in, the rough location, the nearest city.” He estimates that, to date, nearly 20% of the articles on Wikipedia, or more than 1.5m, were first created by his bot. Take that, Georges Simenon.

There was also, it turns out, a gender imbalance in theories of how humans came to speak. Sverker’s general approach in his book is laudably empirical – “I was trained in the hard sciences and the habits of thinking carry over,” he says. Which means casting aside any existing theory that simply doesn’t accord with known facts. And one known fact is that women are just as good as men at using language. One common hypothesis, that language evolved through sexual selection – men competing for the attention of women – can therefore be dismissed. “Women and men talk equally well,” Johansson says. “They have the same language capacity. Unlike songbirds, for example. And that means that an explanation for language has to be gender-neutral or near enough.”

The intellectual field has been notable for its preponderance of confident men with allegedly all-encompassing theories, and Sverker made a point of striking a blow against unthinking sexism. “The position is evidence-driven,” he notes mildly, “but I made a choice to deliberately make it prominent. As, I would say, counter-fire against all the male-chauvinist theories that have been published over the last century.”

This cautious, evidence-based approach sees Johansson, like Sherlock Holmes, eliminating hypotheses one by one. Noam Chomsky’s theory that a brain “grammar” module suddenly appeared by virtue of a single large genetic mutation, for example, is also discarded on the grounds that such a “supermutation” is not “biologically plausible”. Robin Dunbar’s thesis that language evolved out of grooming habits in larger social groups, meanwhile, fails to account for “why baboons, whose troops may contain a couple of hundred individuals, have not evolved an alternative to grooming”.

But group size and social interaction are key in a different way, according to what Johansson finally reveals as his preferred thesis. This is partly inspired by the work of American anthropologist Sarah Blaffer Hrdy, who argues that cooperative childcare played an important role in evolution. Johansson agrees, and thinks that the cooperation necessary was the spark for the evolution of language in turn. “Because human children are so difficult to deliver,” he writes in the book, “having help can mean the difference between life and death.” Midwives and grandmothers turn out to be key.

Any such theory must pass what Johansson calls the “chimp test”: it must explain why chimpanzees, so genetically close to us, did not also evolve language. The idea that language evolved through status-seeking does not pass the chimp test, because chimps already have quite sophisticated politics without needing language. But this woman-centric theory does pass the test, because female chimps leave their birth troupe when sexually mature, and can easily give birth with no help. So special bonds of trust and cooperation are not necessary.

A cluster of such considerations – also taking into account evidence of tool use, culture, and other things – leads Johansson to conclude, in a disarmingly thrilling reveal: “The combination of trust and helpfulness, just the right family and group structure, a language-ready mind and an ecological niche in which cooperation was an advantage turn out to be unique to Homo erectus, and explain why no other animal possesses language.” That is, our ancestors had already begun to talk around a million years ago.

There is much more in the book, including enjoyable sparks of sardonic humour – “In the absence of detailed knowledge about the way mirror neurons work,” he writes, “there is a comprehensive literature that consists in speculation as to what they are for”; or, when discussing animal communication: “When it comes to most of their signals only the squids know what they mean.” It is in many ways a model of popular-science writing in its imperturbable, reasonable weighing of competing ideas. “I hope the reader might see a way of thinking and a way of treating evidence that might be new to many of them,” Johansson agrees.

He’s already at work on a follow-up book to be called The Footprints of Language. “That’s about what happens next, right after we have language. How do we get this enormous diversity of languages that we have in the world today, of 7,000 languages and hundreds of different language families? But it’s not simply chaos: there’s a lot of pattern in these languages.”

Why, crudely, should we care about all this? “Well, there are two types of answer,” he says benignly. “One is basically plain curiosity – where do we come from? The same kind of drive behind creation myths, right? And the other type of answer is more practical. Do we have any use for knowledge about language evolution? And there, I would say, it helps us better understand language itself: the mechanisms of language. And that would be helpful in thinking about language disorders and how to support and repair them.”

In the meantime The Dawn of Language is a fascinating story in its own right, and surprisingly optimistic about human nature, in its emphasis on the necessity of trust and cooperation for language to have ever got off the ground. “If you look at our relatives,” Johansson says, “it becomes rather obvious. We’re not perfect. People certainly fight a lot, but it’s like I wrote in the book – put 300 people in an airplane and they will sit quietly enough across the Atlantic. Put 300 chimps in the same place. What will happen?

“We are not perfect,” Johansson repeats. “But we are more cooperative: we have an easier time cooperating in large groups, and with people we don’t know. We understand reciprocity better: we can do it at larger scales. And we are better at suppressing aggression. Even if you feel you want to strangle the guy across the aisle because he’s incessantly talking, you don’t.” Instead, perhaps, just marvel at the fact he can talk at all.