The silence of the apes

Picture: Bonobo. This piece by Clive Wynne reviews the well-known attempts which have been made to teach chimps (or bonobos) to use language, and draws the melancholy conclusion that the net result has in the end merely confirmed that grammar is uniquely human. It seems a fair assessment to me (though I always find it difficult not to be convinced by some of the remarkable videos which have been produced) , but it did provoke some thoughts that had never occurred to me in this connection before.

According to Wynne, the chimps show clear signs of recognising a number of nouns, but no sign of either putting the nouns in the right order, or recognising the significance of the order in which they have been put by humans. They cannot, in other words, distinguish between ‘snake bites dog’ and ‘dog bites snake’, which is a key test of grammatical competence.

But word order is obviously not the whole story so far as grammar is concerned. One of the first things you learn in Latin is that in that language, although there may be a preferred word order, it isn’t grammatically decisive: ‘Serpens mordet canem’ means the same as ‘Canem mordet serpens’ (to express the reversed relationship, you’d have to say ‘Canis mordet serpentem’). Perhaps apes just have trouble with grammars like that of English which rely on word order; perhaps they would do better with a language which used inflection, or some other grammatical mechanism instead? Was failure, in short, built into these experiments just as surely as it was into the doomed earlier attempts to teach them to speak?

Two quite different languages were involved in the different experiments: Washoe and other chimps were taught ASL, a sign language used by deaf humans; Kanzi and others were taught to communicate in specially-created lexigrams, symbols arranged on a keyboard, though the experimenters apparently used spoken English for the most part.

I don’t know much about ASL, but it does appear to use word order, albeit a different one from that in normal English; typically the topic is mentioned first, followed a comment. You can do this sort of thing in English of course (‘That snake – the dog bit it.’), but it isn’t standard. If you want to specify a time in ASL, which might be done with tenses in English, you should mention it first, before the topic. In making your comment, the word order appears to be similar to the standard English one, though there may be some degree of flexibility. My impression is that ASL users would tend to break down the information they’re conveying into smaller chunks than would be normal in English, taking a clause at a time to help minimise ambiguity. There is something called inflection in ASL, but it isn’t the kind of conjugation and declension we’re used to in Latin, and doesn’t play the same grammatical role. In fact, one important grammatical indicator in ASL is facial expression – a possible problem for the chimps, although they could presumably manage some of the basic head-tilting and eye-brow (alright, brow-ridge) raising.

With lexigrams. the relationship to standard English is closer: each of the 384 lexigrams is equivalent to an English word, and indeed some consist of the word written in a particular shape with particular colours. This obviously makes things easy for the experimenters and in some ways for the bonobos, who would otherwise be faced with learning two languages, heard English and spoken lexigram. The grammar involved is therefore essentially English, and if anything the use of lexigrams makes word order even more crucial, since verbs are necessarily invariant and there are no plurals: so we don’t even get the kind of extra clues we might have in an English sentence like ‘The dog bites the snakes’.

Prima facie then, it does seem to me that unless the chimps were naturally at ease with using English-style word order as their sole grammatical tool, they were actually given little scope to demonstrate grammatical abilities by any of these experiments. We can perhaps follow the implications a little further. ASL is not very much like ordinary English in its grammar or structure. The adoption of a different channel of communication by deaf people appears to have called for a very different language. It seems natural to suppose, then, that if we require even more radically different channels to communicate with chimps we need a language even more remote from English. Perhaps both ASL and lexigrams are too strongly adapted for human use: true communication may require a form of language which is novel and as difficult for human beings to learn as the chimps; one in fact which might require some rethinking of how grammar can be expressed (something similar had to happen before it was accepted that ASL and other sign languages had true grammar). But if merely understanding this hypothetical language would be dauntingly difficult for us, it hardly seems probable that we could construct it in the first place.

The only way such a language could be constructed, I think, is if the chimps were able to make an equal contribution from their side, rather than being captives drilled in an essentially human style of communication. If a human and chimp community enjoyed a close but free relationship of real importance to both, possibly based on trade or similar relations of mutual benefit, perhaps the differing conventions of different species could be shared and a kind of pidgin developed, as happened all over the world when Western traders first appeared – although this time it would have to be a non-vocal one. The chances of anything like this happening, if not zero in any case are of course remote, and growing less all the time, so sadly the chances are that if chimps do after all have some grammatical ability, we’ll never really know about it.

12 thoughts on “The silence of the apes

  1. Very interesting stuff. If you would be so kind to indulge the curiosities of a layman- Have any attempts ever been made to replicate these experiments with languages that have fundamental structural differences? Arabic or Japanese for example? Are there any interesting neurological studies comparing the speech centres of humans and primates? I strongly doubt that a meaningful semantic discourse could be held across the divide of species, but short of that, there must be remarkable discoveries awaiting us in the brains of animals.

    Thanks again for this excellent blog.

  2. So far as I know, there haven’t been any similar experiments using communication systems based on the grammars of other languages. It is a good point; you might wonder whether the characters of classical Chinese might have been better than a made-up system of lexigrams, for example (although the lexigrams use colour as well as shape to aid recognition, so they have one possible advantage).

    One friend of mine considers the mention of trade with chimpanzees, which I indulged in above, to be ‘a bit loony’. I don’t really believe anything like human trade or conversation would ever be possible. However, we should take into account the example of the honeyguide (indicator indicator). This bird, in Africa, attracts the attention of a human partner by specific displays and calls; humans who understand and are interested respond with particular whistles. The bird indicates a direction and distance, and leads the human to a bees nest. The human breaks the nest open, and both partners get honey.

    If a mere bird can set up a partnership of this complexity, it doesn’t seem too wild a speculation to suppose that humans and chimps might have met to exchange say, meat for fruit, and further, might have exchanged signs meaning ‘not enough’, or ‘I want bananas’ or even ‘Same time next week?’. Of course I’m not suggesting anything of the kind has actually taken place, but if it had, it would surely have been the most promising opening for the development of a relatively sophisticated communication system.

  3. Very interesting idea about the inflection-based grammars. It is hard to figure out how you could do this using the pictograms or similar nonalphabetic, nonverbal systems of communication. Too bad monkeys can’t talk! Perhaps birds are a better choice because their vocal apparatus is better developed.

  4. A fascinating topic. I speak as a lifelong programmer with a degree in linguistics and a deep
    interest in the brain. I know of no data that would support this view, but my suspicion is
    that the primate’s grammatical limitations are really due to missing cerebral components
    relating to grammatical structure per se, and really have little to do with how those
    grammatical relations are expressed, either by word order or by inflections. In linguistic
    terms, I am saying that the primate is missing some major pieces of the deep structure,
    while inflection vs. word order are surface structure issues. My intuition is that the
    surface structure would relatively easily be invented if the deep structure were there.

  5. Even if chimps could understand Japanese, these studies strongly suggest that their grammatical abilities are not as adaptable as our ours. Any human child can learn any human language. Even most adult humans can learn most human languages, to a degree. If a chimp cannot learn even one language that a human can learn, that tells us that human grammar is more robust than anything else we know of.

    Of great interest to anyone involved in linguistic research along these lines are two following recent discoveries –

    1. The discovery, by one Dr. Everett, of the Piraha people of the Amazon rainforest, which he claims can speak Piraha but cannot learn Portuguese and have an extremely rudimentary numbers system.

    2. The discovery of a FOXP2 gene mutation, dating back to around 200,000 years ago or so, which appears only in humans and, when altered, causes significant grammatical handicaps.

  6. I am curious about the assertion that Dr Everett claims that the Piraha cannot learn Portugese. Unfortunately I cannot find this claim reproduced anywhere else. Do you have references or a URL I could look at. I have to admit that such a claim, if made, would almost certainly go the same way as the claim that the Inuit have over 120 words for snow.

  7. Controversial is certainly the word! I did rather enjoy Levinson’s arid demolition job in the comments section. Picking just one of the multiple strands of complaint:

    “Blatant inconsistencies likewise do nothing to reassure the reader. For example ,we are told that the
    Piraha are monolingual, but we find that “often this or that Piraha ˜informant would tell me (inPortuguese) that …” and that Piraha ˜“have long intermarried with outsiders,” suggesting sustained bilingualism. Elsewhere it is stated that there are bilingual informants, although their Portuguese is poor.”

    No word for disembodied rabbit parts indeed.

Leave a Reply

Your email address will not be published. Required fields are marked *