Cambridge zoologist Arik Kershenbaum specializes in animal communication, hoping to learn more about the evolution of human language. His 2020 book, Zoologist’s Guide to the Galaxy, (Viking 2020) uses zoology and Darwinian evolution to paint a picture of what extraterrestrial life forms must be like. His forthcoming book is Why Animals Talk (Penguin 2024) and is the subject of an interview with Killian Fox at The Guardian:

He makes the conventional noises against human exceptionalism: “on the one hand, we want animals to talk; but on the other, we’re scared of animals talking because that would mean we’re not quite as special as we thought” But he also acknowledges genuine limitations. Take dolphin names, for example. Fox comments, “I was interested to learn that dolphins have names, or at least signature whistles…” Kerschenbaum replies,

What are these signature whistles for? How do they arise? We still don’t know all that much. You can identify a wolf from the characteristics of its howl, but that’s not the same thing as being a name, and others will not imitate it. So why do dolphins do it? Almost certainly, it’s got something to do with visibility underwater. Maintaining a cohesive social group when you can’t really see where anyone is means you’ve got to rely on sound.

Killian Fox, “Zoologist Arik Kershenbaum: ‘We all want to know whether animals talk and what they’re saying,” The Guardian, January 21, 2024

In other words, a dolphin’s “name” is not a symbolic identifier like a human name; it is a means of identifying podmates under water.

Fox picks up on the theme of human exceptionalism: “Language has been used to set humans apart from other animals: we can speak, they can’t, therefore we’re better. Should we get rid of that idea completely?”

But Kershenbaum hesitates:

There’s no doubt that our behaviour and our ability to manipulate the world are qualitatively different from other animals. And we can say that is because of language. There’s no way we could have created human civilisation without language. So I’m not playing down its importance. I think we are the only species with language on Earth. But I don’t think it’s useful to use that as a distinction. It’s an observation: we have evolved something that other animals haven’t, they’ve evolved things that we haven’t.

Fox, “What they’re saying”

He is evading an issue here, of course: Human language is capable of expressing abstract ideas. Bees can use a complex dance language to communicate where nectar may be found. But that is an entirely instrumental communication system. It cannot handle abstractions and cannot be used for any other purpose.

Interestingly, he does not think animals are evolving toward having a human-like language:

If there were evolutionary drivers for dolphins to have language, they’d have it. But we don’t see them on the cusp. So what that tells us is that in their niche – their environment and the context in which they live – language is not what they need.

Fox, “What they’re saying”

True, but they don’t need human language because they have no abstract ideas to express.

Animal behaviorist Herbert S. Terrace started out believing that chimpanzees could be taught to understand human language. His most famous research subject was Nim Chimpsky — an infant chimpanzee named as a clever challenge to linguist Noam Chomsky (1928–) whose research didn’t support the idea.

However, Terrace came to understand that there is something fundamentally different about the way chimps understand language, as opposed to humans:

Sign language was used because of the physical limitations of a chimpanzee’s vocal apparatus. Nim’s vocabulary grew steadily and he began to combine signs. However, analyses of videotapes showed that most of Nim’s signs were cued by his teachers’ prompts.

Terrace concluded that the only reason Nim (and other chimpanzees) signed was to obtain rewards. Were it not for the teacher, Nim would try to grab a reward directly. When that failed, Nim learned that he had to sign to obtain the reward. Anticipating Nim’s signing, the teacher inadvertently made one or more appropriate signs, about a quarter of a second before he signed. Terrace also showed that prompting explained the signing of other chimpanzees who were trained to use ASL. Because Nim only signed to obtain rewards, his signing was limited to the imperative function of words. That differs fundamentally from its declarative function, which is to name objects conversationally. Imperatives are a minuscule portion of human vocabulary. If human communication were limited to imperatives, language would have never evolved.

Herbert S. Terrace, Psychology Today

Writing about the differences between human language and animal communication generally, he noted the little things that we might tend to miss:

Animal signals, which are typically uni-directional, are never part of a conversation. A vervet monkey who sounds an alarm for a leopard doesn’t expect another monkey to say, thanks, I’ve already seen it, glad you told me, and so on. In those rare instances in which one animal answers another animal’s signal, as for example in bird duets, the answer is innate and immutable. It never adds new information.

Herbert S. Terrace,“Why Animal Communication Is Not Language,” Psychology Today, September 3, 2019

The overall picture seems to be that human language, rooted in symbolic communication of abstractions, is something that other life forms are not capable of doing, and that is why they don’t do it. Evading the reality of human exceptionalism is fashionable but answers no significant question.