Hold the front page: prairie dogs still don’t have language

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Back in February 2010 I posted a piece about Dr. Con Slobodchikoff’s research into prairie dogs and their language, expressing my deep scepticism. This eventually came to Dr Slobodchikoff’s notice and he posted a comment inviting me to check out his webpage, ‘freely available on Google’ he said, where I would find details of the many peer-reviewed research papers he has published on the subject. Well, I did check out his list of publications, and there are lots of them, but none at all in linguistics. Journals like Behavioural Ecology, Mammology  and Intelligent Automation and Soft Computing, are not in any Learning Resources Centre near me, nor are they freely available to people who might want to get hold of them. So I picked a not-too-expensive book, ‘Kinship with Animals’ edited by Solisti and Tobias, in which Dr S. has a chapter about his prairie dog research. Having now read this, I can confidently reaffirm my initial scepticism about them having language. They don’t.

In his chapter Dr S. shows that he has done some homework on the nature and structure of human language, which is only right and proper in anyone claiming to have discovered the same thing in another species.  (For this much he deserves credit, for it’s more than Dr Sue Savage-Rumbaugh or Dr Penny Patterson has ever done in their respective research on the language abilities of bonobo chimps and gorillas.) He states rightly that distinctive features of human language are displacement, productivity and duality of patterning.  Displacement means that human language can describe not just the here and now, but also things and events distant in time and space.  Productivity means that there is literally no limit to what human language can express. Duality of patterning explains how such infinite productivity is possible; a small set of meaningless sounds can be combined in rule-governed ways to make a limitless number of words, phrases, sentences, and so on.

Unfortunately, Dr S. has not understood these features very well. His mistake about displacement is elementary. He takes it to mean the ability to refer to things which are far away, i.e. on the horizon rather than nearby. But this is wrong. Displacement means being able to refer to things which are not discernible, like the dark side of the moon, your lost keys or tomorrow’s headlines. Dogs cannot bark about the cat who came by yesterday, but humans can say the word cat without needing first to see, hear or smell one. Dr S. claims that a prairie dog vocalising about a coyote that was visible on the crest of a hill half a mile away was exhibiting displacement, but until a prairie dog can be proved to be vocalising about the coyote that is too far away to see, hear or smell, or the one that came by yesterday, or the one that might show up tomorrow, no such thing can be claimed. Prairie dog vocalisations are tied to stimuli in the here and now. And this means it is not language.

There is more confusion when it comes to duality of patterning. Here is how Dr S. defines it.

‘A language consists of a duality of structures. The basic units are phonemes which are the smallest units of sound. These phonemes are combined into morphemes, which are the smallest units of meaning. The morphemes are combined into words and the words are combined into sentences.’ (page 65)

Duality of patterning is indeed central to human language. It’s what allows tap, pat and apt to mean different things, and what allows the phrase she has what a man wants to contrast with she wants what a man has: the same units in a different order give a different meaning. Dr S. says this is going on in prairie dog vocalisations, and claims to have discovered the phonemic structures within them. However, phonemes are not physical sounds; they are mental representations of sounds. A phoneme is defined by virtue of the meaningful contrast it is perceived to make with another phoneme.  Physically different sounds which do not contrast in a mental representation, such as [r] and [l] for native speakers of Japanese, or [p] and [b] for native speakers of Arabic, are not separate phonemes but allophones of the same phoneme. So you cannot discover phonemes in a recording of prairie dog whistles by slicing the acoustic signal up into little time segments and looking to see physical differences, which is what Dr S. has done. Moreover, anyone who claims to have identified phonemes should be able to demonstrate what the contrastive units are, which Dr S has not done, at least not in this book. 

Duality of patterning is the driver of productivity in human language. The possible set of combinations of phonemes into words and words into sentences is prodigiously large, infinite even. Any novel thing we encounter can be labelled with a new word, or described by a novel combination of old words. So Dr S. is not modest in his claims. The existence of phonemes in prairie dog vocalisations means, he says, that there is duality of patterning, and by extension there must be an underlying syntax governing the combinations of phonemes in different calls, and by further extension, there is productivity in expression. He says that the prairie dogs in his study could produce warnings about ‘new objects they had never seen before.’ (page 70).  His experiments however, (as least as described here) are unconvincing. The one on page 69 is particularly weak. He showed a colony of prairie dogs a black oval shape travelling on a wire past their burrows, reasoning that this would be an entirely novel thing in their experience. All the prairie dogs who saw the oval made the same new alarm call. Dr. S concludes that all the animals had made up the same new word (sic) for ‘black oval’; evidence, he says, of productivity in their language. It does not occur to him that it is spectacularly unlikely, given the large number of possible combinations their ‘phonemes’ can supply, that all the individuals would come up with the same novel combination. Nor does it occur to him that the vocalisation sparked by the black oval was new to him rather than to them, and it did not ‘mean’ black oval, but was a shared instinctive call roughly translatable as ‘God knows what that is, but it scares the hell out of me.’

 

Dr S. goes even further in speculating about the type of prairie dog vocalisations known as social chatters.

‘Do these chatters contain any meaningful (sic) information that one prairie dog conveys to another? We don’t know. We don’t have a key, a Rosetta stone, to decipher these calls. They could be simply expressions of the internal mood of each prairie dog, communicating no meaningful (sic) information. Or they could be comments on how beautiful the day is.’ (page 71)

Given that Dr. S has just claimed to have found evidence of at least nine ‘words’ in such chatters plus evidence that the words are always ordered in a rule-governed way, we can conclude that he believes nature has not wasted time and effort evolving a complex, hierarchical and rule-governed vocalisation system in the prairie dog just to express private internal moods. And indeed his research continues to search for the key that will unlock what they are saying to each other. (Though as any linguist would point out, the set of phonemes Dr S. claims to have identified for prairie dog language is pretty much the Rosetta stone he says he doesn’t have.) Meanwhile, let us consider for a moment how a prairie dog could even begin to conceptualise a beautiful day.

The arguments for the existence of a language system in a non-human species always begin by taking human language as a yardstick and seeing how far the other species matches up to it. There is an underlying assumption in this kind of research that we are somehow diminishing animals if we conclude that humans have something they lack. This is daft in my opinion, but it explains why researchers looking for humanlike language nearly always find it, even when they have to stretch definitions to the breaking point and delude themselves in the process.  I do not understand why animals need to be seen to measure up to humans in order to gain our respect.  I do not understand why so many of the chapters in ‘Kinship with Animals’ take the line that someone who denies that animals are ‘just like us’ necessarily hates them, or wants to kill them, destroy their habitat, or otherwise abuse them. I like prairie dogs, I am appalled by the way urban development is encroaching on their environment (which I saw with my own eyes last year in Denver), and I would never, ever, harm one. But they don’t have or need language. I am sure of that.

 

(If you have read any of this, Dr S, I hope you take it all in the spirit of constructive criticism which should inform scientific debate. It seems to me that you need a linguist’s viewpoint if you are going to make claims about language, and I hope it helps you make your case more robustly.)

 

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16 thoughts on “Hold the front page: prairie dogs still don’t have language

  1. Good job. This is an incredibly irritating story. The self-styled "Con" Slobodchikoff, whose alter ego or possible supporter posted to the National Geographic Inside Wild blog about this matter last April Fool’s Day, has been running this story since at least 2004 without ever doing the obvious double-blind test: i.e., can a human determine from the computer analysis alone which person (height, colour of clothes, etc) was the subject of which prairie dog alarm call?

  2. Yeah ok, ok, … but PLEASE don’t tell me that dolphins don’t have language too because it’ll only make me cry — and didn’t you say that you don’t like being cruel to animals?

  3. Well said and brilliantly put. And much needed. A linguist would never dream of inventing theories about animal behaviour and expecting them to be taken seriously by the academic establishment, but when it comes to language, everyone’s an expert. It doesn’t even occur to such people to consult someone who knows about language. The problem is exacerbated not only by the desperate desire of animal-lovers to believe they have language, proving that animals are cleverer than we give them credit for and as "good" as human, and a credulous media’s appetite for such crowd-pleasing stories. As you point out, the question of whether there is animal language has nothing to do with respect for nature, and indeed it could be considered disrespectful to our fellow creatures to evaluate them only in terms of how closely they resemble humans.

  4. excellent pts, and it suggests strong limits on the findings. However, it is not clear what turns on the point that prairie dogs dont have "language" as linguists define it as such. Is this the only thing interesting here? I think it is safe without further evidence to concede your pt — prairie dogs dont have anything as robust as human language — it seems equally safe to speculate (rich inner life aside) that they dont have anything like human cognition.But they possess a fairly elaborate communication system nonetheless — for brevity lets call it the "PD sub-language." What is the scope and power of this structure? What functions does it perform in the lives of prairie dogs? What are the limits? What does this reveal about the underlying cognitive structures, their similarity or dissimilarity to our own? But more saliently, why do linguists often seem to be more concerned with guarding their domain as opposed to exploring these issues in a substantive way?while I am sure that the lack of understanding by both the media and external disciplines can be infuriating, this does not seem adequate to me at least to explain the lack of any real substantive engagement.Of course, since i do not regularly read linguistics journals, i could be thoroughly talking out of turn.If so, any recommendations for reading?

  5. &Let’s put it this way. If an ornithologist defines flight as the ability a creature might have to lift its body into the air and control its direction and speed through flapping its wings, then that ornithologist would rightly refuse to allow thegliding of a tree squirrel as flight. The tree squirrel looks like it is flying, but it is liding; it cannot lift into the air, and it cannot increase speed. Physiologically, the squirrel is doing something very different, and very less impressive, than the hawk that plunges from the sky onto a mouse and then soars straight back up.
    Dave asks why linguists won’t allow other animals to be described as having language. This is because only humans use a discrete combinatorial system in which meaningless sound units are structured in rule-governed ways to produce an infinity of expression. We call that language. All the other ways that creatures send messages through  sounds, smells, facial expressions or skin colour are not language because they are non-discrete, non-combinatorial communication systems linked to the immediate present. If a human is unlucky enough to suffer a huge left-hemisphere damage to the brain, her access to vocabulary and grammar is lost. She can still cry, laugh, scream, and swear. She can smile, wave, grimace, point, beckon, raise her eyebrows, go purple with rage, shake her fist, stamp her foot, stick two fingers up. But she cannot use language. This should be illustration enough to show the difference between language and the other ways we have of expressing ourselves, all of which we share with animals.All the questions that Dave asks about the extent of prairie dogs ‘inner lives’ are unresearchable. We can speculate if we like, but we will never know, and that’s why linguists are not exploring this territory. We cannot engage substantively with people who make claims about the inner lives of animals because there is nothing to engage with. I return to the point I make at the end of this post. Why should we start from a position that animals are like us?
    Dave asks for some reading. Try this for a start
    http://www.timeshighereducation.co.uk/story.asp?story

  6. decent article, thanks, although i was hoping for something more academic, and more on the topic of studying more elaborate animal communication strategies that went beyond the usual finger wag.You have misread pretty much all of my points, which has a certain irony given the topic.1) I concede that that prairie dogs dont have language, and suggest we can safely assume they have nothing like human cognition (the "rich inner life" was actually a dig at Dr. S)2) I suggest that whatever you call it, and however you define its scope and limitations, it certainly seems a potentially fruitful domain of inquiry, and one with a lot of potential bearing on linguistics.3) Third, and critically, I commented that at least in my limited experience I have read anything by a linguist on any such topic that was more nuanced than a finger wag, which I find puzzling to say the least. I dont care a fig about whether linguist’s validate or repudiate a claim about whether something counts as "language" — what surprises me is that there is no attempt at a deeper exploration of what is going on (granting outright it isnt the same in any way you choose).4) I noted that it has to be frustrating to read hopeful and anthropomorphic garbage generated not just by the media but by professional researchers who are ignorant (and almost willfully so) of something one has expertise in, and cares about.5) But "defending the fort" is not exactly the most scientific strategy either. Perhaps its simply outside the interest of linguists to refine the spectrum of communication strategies, especially ones that have some overlapped subset with our own. Perhaps I am asking instead for a more intellectually gifted and linguistically savvy ethologist. But I am surprised that the more robust animal communication systems apparently seem to hold no interest to linguists outside of their dismissal. Again, i welcome any reading you have to the contrary, if you have it ready to hand, or a strategy for looking if you dont.thanksDave

  7. Can’t think why any linguist should be especially interested in animal communication systems. It’s like asking a mathematician why she’s not interested in metaphysics. Let intellectually gifted or animal psychologists guess what animals might or might not ‘mean’ by their gestures, vocalisations, etc.; I’m afraid I can’t help out with any robust academic references because all the ones I come across are variations of Dr. Con. For a laugh though, you could look at http://www.koko.org

  8. Having worked in and completed an honors thesis with a cognition lab at my university, I can tell you that linguists may not need cognition scientists, but cognition researchers certainly need linguists. Many psychologists and neuroscientists have only a passing understanding of how human language works and are eager to jump the "language" gun whenever they see any non-human animal acting in any minimally significant way. And personally, as someone who is interested in the way language functions in the human brain, understanding *what* exactly non-human communication looks like in animals’ brains could shed important light on how to separate human linguistic abilities from other associated motor/processing functions.(Also, hi! Big fan of the blog. I just wanted to let you know that a friend and I, recently-graduated linguistics students from Harvard University and Duke University, have started a blog focused on interpreting pop culture and current events through a linguistics lens. We’d really love any feedback you might have for us! The blog is called "The Diacritics" and it’s located at thediacritics.wordpress.com)

  9. HiI”m a huge fan of your blog, and as a linguistics undergrad student I enjoy reading debates on the subject. I think an important point to highlight here is that other sciences and social sciences don’t seem to have to validate their fields as much as Linguistics does. I’m beginning to get the feeling that every time a linguist makes a statement, it is aggressively refuted as if it were a time bomb which if it were to be uncriticised would blow us all to smitherines.Perhaps critics of linguistics could actually read the articles, familiarise themselves with the research, and try to understand the arguments made by linguists before refuting them? Most linguists are not trying to be controversial or argumentative – and great pains are often made to ensure that statements, research, articles, etc, are based on sound, valid evidence.Do other fields get met with the same hostility as Linguistics when they put forward their findings? I find it hard to convince people that we are scientists too.Just my personal opinions and observations 🙂

  10. Hi CarmenI know the feeling, but do take heart; I have never encountered a true refutation, aggressive or otherwise. The most these people can do is bluster and put forward even more subjective and dubious arguments which fall down at the least proddingI think that linguists get a hard time from non-linguists because of the emotional attachment the latter can have to their uninformed views. And we are party-poopers. We don’t accept that cute furry animals have language, we don’t believe that English is the best language in the history of humanity, we don’t think that young people are corrupting their linguistic heritage, and we can’t get excited about apostrophes. What we can do, however, is keep up the good work and trust that time will prove us right, whcih it absolutely will.

  11. There is the further difficulty that those who speak a language think they know all about it by virtue of that fact alone.

  12. …there are numerous examples of languages that at least do not have a canonical word order, and some that have a fundamentally free word order (both with regard to whole clauses and to phrases). Thus the claim that "the same units in a different order give a different meaning" is central to human language is false.

  13. Hi WallyIt is not false to say that duality of patterning (same units in a different order give a different meaning) is central to human language. It is absolutely fundamental to human language. Without it humans could not multiply a few dozen phonemes into an infinity of meanings You are mistaking word order as the only kind of order.And anyway, languages which permit variable word order (such as Latin) use morphology to supply information about such things as gender, case, aspect and tense. This is duality of patterning as well.If you have an example of a language which allows a fundamentally free word order without also using morphology, please let me know..

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