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Wednesday, November 29, 2006

The Big Question: How Did Language Evolve? -- I

The other day, a philosopher I have known for many years and I got into a debate as to how languages evolved. His view is that we are the products of evolutionary processes (which I accept as true) and therefore we should expect to find evidence of some level of linguistic competence in other mammals, including especially apes (something I believe is problematic if pushed too far). The next day, I happened upon a item referring to a Bonobo's (one of the types of chimpanzees closest to humans genetically) having pulled a fire alarm because she was tired of waiting for her tenders let her outdoors. Perhaps I am being a bit dim, but it is difficult for me to see how the Bonobos' setting off a fire alarm is all that newsworthy since dogs evidence similar methods of communication when they want to be let in or let out of our homes (by scratching the door, barking at the door, ringing a bell attached to the door knob, as well as other dazzling tricks). What grabbed my attention is that in the original Associated Press story I found this remarkable claim:
Bonobos are one of the most human-like of the great apes and have sophisticated language skills.
Ah, "sophisticated language skills." Give me a break. Bonobos may have "sophisticated communication skills," but that is very far from saying that they have "sophisticated language skills."

This is a journalist's claim, not a scholar's claim but it illustrates the problem we face in discussing the evolution of language. We must first make clear that we are talking about language, not communication, something which clearly is possible in the absence of language. The problem with this is that some are willing to take damn near any signaling system found in nature as an instance of linguistic communication. Compare what Ula Hedeager says about language
Birdsong appears to have much in common with human language.
with what John Limber says
An organism uses human language if and only if it uses structures characteristic of those languages.
You will perhaps not be surprised to learn I side with Limber.

The fact is that human languages are extremely complex. I entered into the third class of linguistic students at MIT in 1963 and from then til now not only has no language been exhaustively described, linguists are not agreed as to how to go about describing sentence structure of languages. Empirically sound, mathematically based descriptions of language are very difficult to come by.

Nevertheless, some minimum requirements a putative language must satisfy can be established. It should, for instance, exhibit a capacity for dealing with what we call "grammatical relations." The most basic grammatical relations are those that hold between subjects and predicates and verbs and their objects. In English we have sentences like
1. John loves that girl.
2. That girl loves John.
3. That girl, John loves.
We have three sentences here containing the same words/symbols but three different word orders. We know that in any circumstance in which 1 is true, 3 will be true and from this we may conclude that they have the same conventional meaning despite the striking difference in word order, a difference that we use to signal secondary meaning (emphasis, perhaps). [It is not uncommon for a set of sentences with the same conventional meaning to vary in secondary meaning or significance -- in this case, the speaker implicates that this girl is the only one of a set of girls that John likes.] On the other hand, 1 can be true when 2 is false and because of that we must conclude that they differ in conventional meaning.

One can complicate this problem a bit by introducing pairs like
4. Barry told Sam that {John likes that girl}.
Here we have something closely resembling a sentence (number 1 above) being embedded inside another sentence. This device of embedding is one of the devices we exploit to create what Chomsky famously called "novel sentences." The braces here illustrate the fact that the sentences of human languages exhibit hierarchical structure. It is characteristic of humans using human languages that we routinely construct sentences neither we nor anyone else has ever uttered. I'm betting that there are a bunch of these novel sentences in this blog.

Even more interesting are cases of what are often called "unbounded dependencies." Observe that in sentence 5, no less than in 4, "which girl" is the object of the verb "likes."
5. Which girl did Barry tell Sam that {John likes e}?
I am using "e" to draw attention to this fact. This ability is a very exciting one, especially when one realizes that the limitations of humans to handle such phenomena have more to do with our short term memory limitations than our cognitive abilities. I think that most people would have little trouble handling a sentence like 6. in which "which girl" is still the object of "likes."
6. Which girl {did Barry tell Sam that {Susan thinks {John likes e}}}.
It is because of data like 6 that the dependency between "which girl" and "e" (the extraction site) that we say that this phenomenon is unbounded.

The question is whether Bonobos or other apes can handle such phenomena. No one has ever proved they can to my knowledge. And until they can prove this I will be disinclined to think that they have "sophisticated language skills." One of the problems with evaluating claims made about the language skills of apes is that researchers have sometimes exaggerated their abilities. I would recommend that one examine any such claims with a skeptical eye.

Every study I have ever read which has tried to compare ape language skills with human language skills has put the former at about the 2 to 3 year old levels. This is a nontrivial accomplishment but falls short of showing that these primates have anything like the competence of human adults or even 12 year old children. One of the problems in teaching primates language is that the ideal form of language to teach is ASL since their ability to make human language sounds is severely limited and it has proved to be difficult to teach them to sign in part because it involves "modeling" the signs by physically helping the primate to make the sign. Remarkably, I just found an Ohio State University web page discussing the teaching of sign language to infants as young as 9 months. It seems that human infants have sufficient motor skills to do some signing before they have the motor skills required to produce human speech. This is wild and crazy stuff.

Researchers seem to have had more success teaching apes to use of plastic chips as symbols for things or keys on a keyboard. Though it is just a PowerPoint summary type presentation, you may find Apes using sign- or symbol-based languages useful as a summary of efforts to teach primates language. If you can't load that set of pages, you may find this html page helpful.

Let us recall though that absence of evidence that primates have a language ability comparable to humans is not evidence of its absence. There are real problems involved in teaching primates language having to do with their physical limitations both in regard to producing sounds and making the manual gestures required for something like ASL. And there is Wittgenstein's claim that even if a lion could talk we couldn't understand it to deal with it. There is an interesting thread at the Philosophy Forum on this. I side with Tsunami's remark, which was the second item in the thread. A chimpanzee or bonobo simply may not care about the sorts of things we like to talk about. It likes food and to play and to do other primate things. The concept of "liking someone," essential to understanding sentences 1 through 6 may be so foreign to the world of the Chimpanzee or Bonobo that it could simply not understand it.

I'm going to stop here and collect your thoughts before proceeding. Besides this blog is already overlong. Next we will focus on what can be learned by my fairly ignorant self about the evolution of human and other primate's sound production devices and brains. As you will discover, I use writing as a stimulus to learning.


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30 Comments:

Blogger L>T said...

This comment has been removed by the author.

8:43 PM

 
Blogger L>T said...

I understand that language is complex & not the same as animal communication. But doesn't language have to start from somewhere? Like the desire to communicate. I always assumed that babies are just trying to communicate. I mean, what do babies know about language?

Something just clicked in my brain. If humans didn't have vocal cords, we'd still have language. that I find interesting.

12:06 PM

 
Blogger IbaDaiRon said...

I mean, what do babies know about language?

Depends on who you ask, doesn't it? Chomsky would say they know everything in general and are just waiting for the specifics from the adults around them.

But what does he know? :)

It should be uncontroversial that babies are born with the potential to become human-language users. The controversial question is the form of that capacity.

Some things I think are important to remember, off the top of my head:

1. Human language developed from a primate communication system, but it's a whole nuther critter (different in kind).
2. Animal communication (sending of signals) is not always accompanied by some sort of desire to communicate.
3. Homo sapiens is the last in a long line of developmental stages, as are modern primates. The communication systems of both are different from that used by our common ancestor.

If I have time today, I'll post that list of distinctive characteristics from the OSU Language Files on a permanent page on my blog. It makes for a useful reference when thinking about these things.

6:16 PM

 
Blogger L>T said...

Thanks ron, I got it. :)
LG, please DO continue with this, it's interesting.

9:01 PM

 
Blogger Kelly said...

I agree with you completely on this, LG. Somehow I doubt that a bonobo's capacity for using symbols is any different in kind from a dog's. For example, my dog Russell understands the words "walk," "outside," and "Dempsey" (the name of my in-laws' dog) perfectly well. Some people will insist that it's the tone of your voice that affects his excitement, but I know that's not true because he answers to them in any tone of voice, even a subdued tone of voice speaking to another person. He also responds to these words differently, so they're not just simple cues to excitement. For "walk" he will go to the front door, where we exit for walks. For "outside" he will go to the back door, where we let him out for his personal business. For "Dempsey" he will bark and then go to the window and look outside, expecting Dempsey to be coming to the house (this often comes up when talking to the in-laws over the phone). This is the same in kind to an ape's understanding, although the number of symbols is likely much more limited.

But, just like an ape, he can not appreciate syntax. "Come here" and "go inside" are commands he can understand, but to him they are undoubtedly each one symbol, not two combined. He understands "no" but if you were to say "no walk" he would believe he was doing something wrong but that we were also going to go for a walk. I doubt any ape could do any better. If they show any evidence of this, it's likely just conditioning to respond to two symbols as one symbol and not evidence that they appreciate the interaction between the two symbols.

Now, if instead the apes were able to come up with what you call "novel sentenes" (which I assume are sentences they never have heard), then it might be said that their capacity for communication is different in kind from that of dogs (whether it's linguistic or not I'll leave up to the experts). Perhaps if an ape would sign symbols for "no," "hug," and "John," each symbols that they understand, and indicating a willingness to perhaps hug other people but not John, then I might take more interest in their research. If they can't do this, then they're just playing with animals and doing nothing of any more moment than when I teach my dogs to shake hands--it sure looks human, but despite all of our similarities it's nothing to indicate that we're the same.

9:22 PM

 
Blogger IbaDaiRon said...

I've known a few dogs in my time but have never been around a bonobo; all I know of their mental capabilities is what I've read.

It's clear that they have not developed a human-like language on their own and that they are capable of learning only some aspects of the symbolic manipulations involved in using human language (as a result of directed teaching, not passive acquisition through normal interaction like human children).

I would be very careful, however, in equating the mental capacity of one animal with another. There should be a spectrum of abilities, with a wide gap between humans and whatever comes closest to us.

12:45 AM

 
Blogger SusieQ said...

Here is an article about language and apes at the NPR website.

http://www.npr.org/templates/story/story.php?storyId=5503685

I don't think apes possess language skills of the kind LG describes. But what we have been able to find out about apes and their ability to learn communication skills and use them not only with humans but also with fellow apes causes me to have a lot more respect for their intelligence.

Kelly, we have a collie. None of those one word commands for me. I talk to our collie Max in sentences. I alter the sentences from time to time and he still gets the drift. He is smart. But the breed which runs away with first prize for smartness is the border collie. They have been known to use deductive reasoning.

12:51 AM

 
Blogger Language Guy said...

L>T, without vocal cords there would never have been language. Purely and simply. The descended larynx, vocal cords/folds included are the biggest anatomical difference between humans and apes not involving the brain that has a bearing on the existence of human languages.

Humans who are uninformed tend to think that languages are not all that complex since they are totally unaware of how they learned them. Anything that "east to learn" can't be that complex, so I think they reason. Chomsky has his answer to that. But there are others.

The key question as we shall see is whether the evolution of language was in one big jump or gobs of tiny ones. Also, one must deal with the issue of the anatomical changes -- larynx, tongue, etc. not haveing to with the brain directly -- and brain changes. IMO right now, the latter preceded the former, meaning that we were cognitively pre-adapted for language when the larynx came to be available to making discrete sounds. We took advantage of it.

9:02 AM

 
Blogger L>T said...

LGO.K. I think i get it. I was thinking that if humans didn't have vocal cords, we'd have come up with a sign language just as complex as spoken language. But you are saying that it all goes together? You can't seperate the cart from the horse.

Speaking of that & animals, our cat has never been able to meow, he's never been able to make anything but an "ack" sound. But, he can communicate what he wants to us as well as any other speaking cat as far as I can see. Of course if he could meow he would. He's wired to meow, right? He's had to adapt & come up with his own cat sign language, but he's not any smarter then any other cat because of it.

10:44 AM

 
Blogger SusieQ said...

LG, does the little we know about feral children and their struggle to learn language lend any understanding to the issue of apes and language?

I watched a TV program about feral children a few months ago. One feral child who was quite a bit older when she was discovered had great difficulty forming sentences. However, she was able to acquire an impressive vocabulary.

10:30 PM

 
Blogger Kelly said...

Susie, I too talk with my dog in complete sentences. But I think they cue onto certain words that come up in those sentences often. They also pick up on nonverbal cues (which to use the technical, communication arts/sciences sense also includes tone of voice) but I wanted to emphasize that Russell could identify certain words.

As to animal intelligence:
I don't doubt that some dogs are very bright. Dempsey, whom I mentioned, has shown ability to plan and reason, to an extent. For instance, one time he was playing with another dog, and that dog went under a bed. Dempsey jumped on top of the bed and waited for the other dog to come out. He had never played with this dog before, and had never seen another dog go under an object, to my knowledge (all the other dogs he comes into contact with are too large to do this).
I think, however, that thinking in terms of "more" or "less" intelligent is the wrong way to go about it. There is a bird species that lives in North America that buries thousands (tens of thousands?) of pine nuts each year, and it finds something like 98% of them, even though they're spread out over many square miles and under a changed landscape (snow). Humans certainly couldn't perform this feat of mental prowess.

12:24 AM

 
Blogger Language Guy said...

A problem with feral children is that they are often abandoned because they are defective in some way, possibly retarded. You are right that they do not learn languages effectively if they are too old but that too could be related to retardation.

7:26 AM

 
Blogger L>T said...

When it comes to teaching apes sign communication or parrots to talk for that matter, or our dogs & cats to reconize their names, humans initiate all of it. We are teaching them tricks & pushing their limits for food, animals will do anything within their power for food. Apes & parrots in the wild apparently have no desire to form languages, they've figured out other ways to get food. I bet my cat who I like to think loves me would leave if I didn't feed him. I think there is alot of wishful thinking on the part of humans to want animals to exibit human traits. I read somewhere that dogs only speak on word & it's "Hey!"

10:06 AM

 
Blogger IbaDaiRon said...

Humans certainly couldn't perform this feat of mental prowess.

I know tens, maybe hundreds, of thousands of words. I can usually find any one them 99% of the time, and usually within milliseconds.

:)


L>T, I think I saw that as a comedy short once. A bunch of shots of different dogs with superimposed "conversation balloons" all saying only "Hey!" Pretty funny, especially the shot of a doberman coming up and sniffing a chihuahua and the chihuahua turning its head and looking up at the other dog.

"HEY!"

Animals in the wild have no need to form languages; they already have evolved communication systems sufficient for their needs.

The origin and evolution of human language, intelligence and civilization is a bit of a chicken-and-egg problem, IMO.

4:42 PM

 
Blogger Kelly said...

L>T and Ibadairon, that was a The Far Side cartoon which featured a man who had invented a machine that would let him know what dogs were saying. Others may have copied it since.

Speaking of chickens and eggs, or at least just chickens, they have distinct calls for notifying others that there are predators around. There are at least two different such calls, one for air predators (which informs the others to duck--another fowl [sorry, had to]) and another for ground predators (and I can't remember what they do in response to this). I'm not sure if this is entirely in their genetic code of whether it's learned.

But L>T, I think that some animals do very much display human traits. I highly doubt that my dogs would leave me if I didn't feed them. But that's because they're pack animals and they've been bred for thousands of years to coexist with humans and treat them as members of the pack.
On the other hand, it could be that humans just display some animal traits, like pack loyalty and play behavior, and that animals don't display any human traits.

10:45 PM

 
Blogger SusieQ said...

Kelly, dogs probably do pick up particular words when we speak in sentences to them. I think also that they hear sentences and phrases as if they are one word. The command "Do your business." surely must sound to a dog like "Doyourbusiness." Like other species, they are adept at reading body language, probably because body language is one of the ways in which they communicate. Also, they pick up on cues that humans might be oblivious to. For instance, long before I leave the house to go shopping or whatever, my collie knows I am going. He has learned that when I do certain things it signals my eventual departure from the house which he doesn't like because it means he has to stay in the utility room while I am gone.

I get your point that we should not think of intelligence in terms of "more" or "less". Animals have undergone specialization so that certain animals are especially good at certain things in order to survive in their given environment. Your bird species that buries thousands of pine nuts and is able to find close to 98% of them later on is a prime example. Except in the case of language perhaps, humans have not undergone specialization maybe because we are still the new kids on the evolution block so to speak. We are flexible and able to adapt to almost any environment. Maybe this is due in part to the development of language.

Today I was reading an article at Wikipedia about animal language. I ran across mention of a chimp whose name was Nim Chimsky. Funny!

LT, cats are independent. You never know for sure where you stand with a cat. But a dog is a different story. You know where you stand with a dog. It is true that dogs, for instance, do not ask us to teach them how to roll over and stuff like that. We initiate that. But I don't think their only interest in learning these tricks is so they will get rewarded with food. Dogs want to please us.

As far as humans wanting animals to exhibit human traits, well, in our neighborhood we have many dog owners. These dog owners make play dates for their dogs. Now I love animals and I love my collie, but I have not yet gone the route arranging play dates for him.

I agree with Kelly about animals displaying human traits. We call certain traits human ones, but they may be just plain old animal traits which we share with some of the other animals. It has already been established that some animals are capable of compassion and sympathy for instance. And we all know how arrogant and self-centered cats can be at times.

11:08 PM

 
Blogger Kelly said...

There was a theorist once (around the 15th-17th centuries) who tried to categorize animals as lesser and higher animals (in true neo-Platonian/Augustinian style). I can't remember how he arranged the lowest levels, but cats were fairly high on the list because he thought they were capable of malice. Dogs were a step above them (and I think they were at the highest level) because they are capable of loyalty and compassion.

9:24 AM

 
Blogger Kelly said...

You'd be surprised how much you can learn in an animal behavior class where you do nothing but watch documentaries and read a textbook. I still remember all this stuff after about four years because it made such an impact.

9:26 AM

 
Blogger Language Guy said...

When I went to the Chicago Museum of Natural History (I think that was its name) in the late 60's or early 70's, I was amused by the anthropomorphic descriptions of animals. The hyena was roughed up pretty badly by the naturalists there.

I saw a nice documentary on digs in Montana for T-Rex remains. The person in charge of the digs was promoting the theory that these beasts were not predators but rather were scavengers, arguing that they were not built for speed and that they had a powerful olfactory system characteristic of scavengers who need to be able to smell dead things from great distances.

10:40 AM

 
Blogger L>T said...

I agree with Kelly about animals displaying human traits. We call certain traits human ones, but they may be just plain old animal traits which we share with some of the other animals. Of course that's true in a sense. & you could say a cat displays traits of arrogance & self-centeredness or that dogs display traits of loyalty. But, that's only how they appear to us, we are interpreting those traits. No animal(to my knowledge)is capable of telling us "Yes, this is how I feel about it." They can't even communicate that much. Their abilities that we see as human like traits are all based on our assumptions. No matter how much a person wants to elevate their pet to human status, turn it into some kind of surrogate baby, or whatever.Or in the case of apes, some sort of mini-me.

10:40 AM

 
Blogger L>T said...

Personally, I think humans live a whole nuther(see how I combine the words another & other, is that what you call sematic drifting?) reality then animals no matter how much we try to drag them into it.
I suppose this is where language comes in...

11:01 AM

 
Blogger Kelly said...

LG, I've heard a little about that theory, and it makes sense. I believe I heard somewhere that condors (a scavenging species) have the largest olfactory cavities of any species alive today. In addition, the large prey they would need to take down (considering their size) could be very damaging to them, so they might have trouble living very long. On the other hand, though, sharks can smell things very well too. This has gone completely off topic, but it's interesting.

12:46 PM

 
Blogger IbaDaiRon said...

Sorry, but I don't see how loyalty and compassion have any direct connection with rating intelligence.

(LG, did the documentary detail the expert's reasons for concluding T-Rex was "not built for speed"?)

5:38 PM

 
Blogger SusieQ said...

"Personally, I think humans live a whole nuther(see how I combine the words another & other, is that what you call sematic drifting?) reality then animals....."

So? Aborigines in Australia experience a whole "nuther" reality than New Yorkers do.

" No animal(to my knowledge)is capable of telling us "Yes, this is how I feel about it." They can't even communicate that much."

LT, my collie tells me how he "feels" about things through his body language, his yelps, barks, growls and so on. He can't use words to convey his feelings, but this does not mean he isn't interested in conveying his feelings through other means. We don't have long drawn out conversations about what he feels, but I get his message nonetheless. And he gets mine! We communicate with each other the best we can.

Here is something interesting I pulled from this site: http://archives.cnn.com/2002/TECH/science/11/21/coolsc.dogorigin/

"It looks like dogs really do understand what we are trying to tell them, they are thinking about what we want, and they understand that we are trying to communicate," said Brian Hare of Harvard University, who authored one of the studies."

AND:

"Domestic dogs follow humans like a laser and watch the behavior of their humans with a focus that is astounding," said McConnell, a professor at the University of Wisconsin in Madison. "This opens up big and interesting questions about how social intelligence is passed on genetically."

I don't know, LT, maybe I have seen too many Jane Goodall documentaries. But I think some of us are threatened by the idea that we may have more in common with the "other" animals than we originally thought and that "other" animals may be more intelligent and capable than we originally thought. It would be absolutely disgraceful if we discovered that humans as a species are not as high and mighty as we originally thought.

This is what Jane Goodall said about chimpanzees: "How should we relate to beings who look into mirrors and see themselves as individuals, who mourn companions and may die of grief, who have a consciousness of 'self?' Don't they deserve to be treated with the same sort of consideration we accord to other highly sensitive beings: ourselves?"

8:50 PM

 
Blogger SusieQ said...

Oh, and LT, I was just kidding about cats being arrogant and self-centered. That is a standing joke about cats.

9:33 AM

 
Blogger L>T said...

Susie So? Aborigines in Australia experience a whole "nuther" reality than New Yorkers do. whatever makes you think I meant that?

O.K. so animals can communicate with humans. to a certain extent on a certain level.
"A dog cannot relate his autobiography; however eloquently he may bark, he cannot tell you that his parents were honest though poor." Bertrand Russell

we may have more in common with the "other" animals than we originally thought and that "other" animals may be more intelligent and capable than we originally thought. I have no problem with that.

Of course animals deserve to be treated with compassion & respect. We don't have to elevate them to the status of humans or pamper them to do that. I imagine chimps, etc...would prefer to be left alone in the jungle to swing from trees & have as little to do with us as possible. & dogs would prefer to run around & sniff each others asses & hang around with other dogs & kill things if they could. Animals don't want to be like humans, but alo of humans want to be like Dr, Dolittle.

10:55 AM

 
Blogger Kelly said...

L>T, I think you're absolutely wrong about dogs. They might prefer to be with other dogs, but at the end of the day they're as attached to human faces as is a human baby. Thousands of years of natural (and artificial) selection have bred them to enjoy being around humans.

10:35 PM

 
Blogger L>T said...

kelly Honestly, how long do you think it would take for that breeding to disappear & they would be eating your babies like Dingos?

11:33 PM

 
Blogger IbaDaiRon said...

Why am I suddenly reminded of Lord of the Flies?

And plagued by this image of a chihuahua eating an opera diva?

Oh well. As we used to sing in Houck House at OSU,

We are a pack of wild dogs,
A pack of wild dogs are we!
We roam the hills,
Bereft of job skills,
And don't care where we pee!


(LG, I think it's time to move on to Post #2!)

9:30 PM

 
Blogger Freudian Slip said...

It makes me wonder how we as humans will communicate in 200 years. Technology has changed things so much. What will the next big change be!?!
Matt

11:57 PM

 

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