“Ever since I was little, I’ve wanted to become a real-life Doctor Dolittle,” says Lucy Cooke, introducing a new BBC series on animal communication. It’s a fantasy many of us share. Some believe they’ve already achieved it – a colleague is convinced that she is able to have a civilised conversation with her tabby, Coco.
And then there are the celebrities of the animal communication world: Nim Chimpsky, Peter the dolphin and Alex the African grey parrot. Their feats have rightly made them famous. Nim is reported to have learned over a hundred words in American sign language, and produced sentences such as “tickle me Nim”. Alex was able to ask for water, to count, name colours and say what objects were made of after touching them with his beak. His final words (he died in 2007) were apparently “You be good, see you tomorrow. I love you.”
In a recent breakthrough, scientists used a computer to perform simultaneous translation of a dolphin’s requests to play with seaweed. Earlier researchers used far less orthodox approaches to get close to these highly intelligent creatures, whose brain-to-body-size ratio is second only to humans.
What’s clear is that animal communication can be extraordinarily sophisticated. But is it ever language? Could a parrot write a novel? Is a dawn chorus as complex as a parliamentary debate?
Just over 50 years ago, American linguist Charles Hockett identified what he called the 13 “design features” of communication. Only human language, he argued, contained all 13, and certain crucial properties distinguished it from such things as honey bee dances and gibbon calls. Here are some of them:
Any member of the species can produce any of the signs used in the system. This isn’t the case with all forms of communication: Hockett uses the example of the mating dance of the stickleback, which is done differently by males and females – and “neither can act out those appropriate to the other”.
The relationship between signs and the things they signify can be random. If I were to invent a new language, I could decide that “blop” meant table, but equally, “polb” would do. Contrast this with onomatopoeic words such as “rumble” or “crash”, which exhibit at least some phonetic similarities with the things they’re describing. This is called iconicity. The form of a bee dance, which is used to communicate to other bees where nectar can be found, has a direct relationship with the path to be taken.
Language is made up of separate, identifiable units. These include sounds, known as phonemes, that distinguish one word from another – like “pin” from “bin”. When a different phoneme is used, the shift from one meaning to the other is clear and immediate. A gibbon screech, on the other hand, may change from meaning “I’m here” to “I’m angry” simply by getting louder or more emphatic. This is a continuous change. Likewise, a bee may waggle a bit more quickly to indicate greater distance.
Language allows us to refer to things that are distance in space, or in time. Animals tend to react and communicate about things that are right in front of them – like a mongoose danger call provoked by a bird of prey. Gradually, however, evidence has accumulated that many animals are able to refer to things that aren’t there – as with by Kanzi the bonobo, who is able to use a communication device to ask for the ingredients for one of his favourite dishes, omelette.
Language has two levels: one which has meaning – words or signs that can be interpreted in and of themselves – and another which is meaningless but still obeys certain rules. Units such as phonemes exist on the second level, but are added together to make words. This property allows a restricted number of meaningless units (such as those 40 or so sounds we are able to produce using our vocal chords) to be combined to produce billions of different words, giving language enormous flexibility.
Language can be used to say completely novel things. It does not struggle with the unexpected, and can easily be used to say that there’s giraffe with green spots in the living room. Many animal calls are fixed and cannot be combined in order to describe new situations.
Though higher animals are able to combine adjectives and nouns to describe new situations – even make analogies (Alex called dried corn “rock corn” because it was hard) – it is productivity that animals really fall down on. Their systems of communication lack a particular feature of human language, called recursion. It’s a property of the way we order words that means the number of sentences we can produce is theoretically infinite. For example, I can say: “David wasn’t pleased with Michael”. I can also say “Theresa said that David wasn’t pleased with Michael”, “George didn’t believe that Theresa said that David wasn’t pleased with Michael” and so on, for ever and ever. As far as we know, dolphins are just never going to be able to get their heads round that.
The deep structure of sentences was something revealed by Noam Chomsky, a strident advocate of the exceptionalism of human language. But though we may not have yet found any similar system among animals, that doesn’t separate us from the natural world as decisively as you might think.
Alex’s “mother”, Irene Pepperberg, has asked, “what do we learn if we find that a particular trait is or is not restricted to humans?”. It’s worth pondering this, given the way syntax has been used to support the idea that human intelligence is a wondrous one-off. She argues that distinctive properties of communication systems are simply the result of different ecological and evolutionary pressures. The particular quirks of human syntax could emerge in another species if the conditions were right. Of course, we regard them as special because they’re ours. But they evolved once, and they could evolve again – and may, in some rudimentary form, already be out there, waiting to be discovered.
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