MAN TALKING TO CHIMPANZEE: I see the ball over there. Can you get the ball? Yes. Thank you.
PAUL HOFFMAN, Discover Magazine: Scientists have long thought that language is unique to the human brain and that our ability to use it is what separates us from the rest of the animal kingdom. An ape research project in Atlanta is challenging this claim.
MAN TALKING TO CHIMPANZEE: Pambinisha, can you tickle Sue? She's waiting.
WOMAN TALKING TO CHIMPANZEE: Ah, that was so sweet. Thank you, Pambinisha.
WOMAN: The velvet plant and the back pack.
MR. HOFFMAN: Konzi is a Benobo, a pygmy chimpanzee. He and his sister, Pambinisha, are the subjects of Doctor Sue Savage Rumbaugh's work. That work is questioning the widely accepted view that only humans are capable of language. For 20 years, she's been studying whether Benobos can learn language, working first with their mother, Matata, back in 1975.
SUE SAVAGE-RUMBAUGH, Georgia State University: We were trying to do some very simple things like hold up an apple and teach Matata to hit the symbol for apple, and then we would give her an apple. She learned that. What we wanted then to be able to do was to have her use the symbol for apple whenever she was talking about an apple, whether she was intending to eat it or not, to know in a sense that the symbol represented apple, not just the fact that she was going to get apple. This, she couldn't learn, but fortunately, she had a youngster named Konzi, who was around and was playing while I was trying to teach her, and Konzi did learn, even though we weren't trying to teach him. What we found with Konzi was that simply by watching what we did with his mother, he was able to make this correlation so that he knew that the symbol apple represented apple, whether he got to eat one, whether his mother got to eat one, whether we were saying, no, Konzi, don't eat an apple, it still meant apple.
SUE SAVAGE-RUMBAUGH: (working with chimpanzee) Can you find melon? Good. Good job. Can you find potatoes? Good job.
PAUL HOFFMAN: Benobos lack the vocal apparatus to make the range of sounds that humans do, so here at the language research center at Georgia State University, they've designed a special keyboard that allows two-way communication with the apes.
SUE SAVAGE-RUMBAUGH: Wonderful! Wonderful!
PAUL HOFFMAN: The board contains 256 symbols, each representing a specific word. For instance, this is a symbol for milk and this is a symbol for chase. When Savage-Rumbaugh talks to Konzi, she points to the symbols corresponding to what she's saying. Konzi can respond by pointing back. He seems most interested in food, tickling, and biting.
SUE SAVAGE-RUMBAUGH: (talking to Konzi) What are you thinking? Tickle and bite. Okay. Yes, I'm going to tickle and bite Konzi, if you can do one thing for me. You know what I want you to do for me? I want you to get the telephone and do some talking on the telephone. Could you go get the telephone and do some talking?
PAUL HOFFMAN: It may seem easy to conclude that since these apes are communicating, these apes have language. But this is still a very controversial conclusion because it calls into question what most scientists believe is unique to human beings.
SUE SAVAGE-RUMBAUGH: (talking to Konzi) You don't hear anybody?
PAUL HOFFMAN: Over the years, anthropologists have pointed to many differences between our species and animals, for example, our ability to use tools. But then scientists observed the sea otter using rocks to break open mollusks, so anthropologists raised the bar, claiming that we were the only animal that makes tools, until in 1960, chimpanzees were observed stripping leaves and twigs off a branch and using it to fish termites out of a nest. Now Savage-Rumbaugh and her husband and collaborator, Duane Rumbaugh, believe that their work undermines what is arguably the last bastion of human uniqueness, language.
DUANE RUMBAUGH, Georgia State University: If Konzi can hear a novel sentence of request and respond to it logically and adaptively the first time that he hears it, how can you say but that he has the comprehension base of language?
PAUL HOFFMAN: To support the thesis that Konzi comprehends language, Savage-Rumbaugh has set up a controlled testing situation where Konzi is asked to respond to sentences he hasn't heard before. She's wearing a welder's mask to avoid cuing the correct response.
SUE SAVAGE-RUMBAUGH: (talking to Konzi) Give the doggy a shot.
PAUL HOFFMAN: There were 600 sentences in the experiment, all designed to use different grammatical forms and to be as unpredictable as possible.
SUE SAVAGE-RUMBAUGH: Good job. Okay. Thank you. Put the key in the refrigerator. Good job. Thank you.
PAUL HOFFMAN: Savage-Rumbaugh claims that Konzi responded accurately 75 percent of the time, equivalent to what a two-year-old child did in a similar setting. But does this prove that Konzi has language? Not all scientists believe that does. Dr. Laura Ann Petitto is a language researcher at McGill University in Montreal. Today she studies humans, but 20 years ago, like Savage-Rumbaugh, Petitto tried to teach language, sign language, to chimpanzees. For three and a half years at Columbia University, she lived with a chimpanzee named Nim Chimpski, named after linguist Noam Chomsky, who maintains that humans are uniquely hard-wired for language.
LAURA ANN PETITTO, McGill University: When I entered the chimp project, I was absolutely convinced I was going to see language in apes. They have all these other capacities that would suggest language. They are cognitively complex. They can categorize. They can serial order. They had complex memory. They can enact. They can lead me to the place where they hid things, and yet, they couldn't take the symbol to stand for that and tell me about it.
PAUL HOFFMAN: The answer, she believed, would be revealed by studying humans. She suspected that there was something in the human brain that aided children in acquiring language. After a decade of research, she concluded that children learn language in a fundamentally different way from apes.
LAURA ANN PETITTO: Our brains at birth have a specific sensitivity to timing and rhythmical patterns of the human voice, and that gives the child a tremendous kick-start--a tremendous thrust into the process. It allows--the sensitivity just to their mother's undulated patterns in her voice allows a child to find the beginning and ends of words, allows a child to extract out little chunks of sound, the building blocks of sound that we form when we form a word.
PAUL HOFFMAN: We call this behavior "babbling," and virtually all human babies do it, while apes do not. Even deaf children babble, Petitto discovered, by using their hands instead of their voices. This babbling behavior, she argues, is critical, because it is how children first play with the raw building materials of language. Later, they will fashion these materials in infinitely creative ways, which is how they understand the world and impose order upon it. By contrast, Petitto says, apes are almost always seen making or responding to requests. When Petitto looks at this, she sees Konzi making associations, but she argues human language goes beyond mere association. For example, Konzi knows the symbol for peach but can't comprehend that it's a type of fruit. According to Petitto, Savage-Rumbaugh has concentrated on the similarities between apes and children which are, indeed, compelling but has ignored the many striking differences.
LAURA ANN PETITTO: We know that an aspect of learning a language involves association, and it's a truism that aspects of acquiring natural language involve learning. But we also know that learning is insufficient as a mechanism for our species to acquire the entire range of what we know about human language. Learning alone--I could not possibly have learned exclusively from my mother all that I know about language, all that I'm doing with language. It is not--it's not biologically possible, and nor is it commensurate with any of the biological data that we have.
SUE SAVAGE-RUMBAUGH: (talking to Konzi) You want a popsicle? Okay. Yes, you may have a popsicle.
PAUL HOFFMAN: According to Petitto, these apes are not using language but they are communicating, associating, and problem solving. They're able to do this, she claims, because these properties are housed in a primitive brain stem, a part of the brain we share with other species, including other primates. But to Savage-Rumbaugh, the ape's behavior is communicative, and that's how she defines language.
SUE SAVAGE-RUMBAUGH: Now I understand in ways that I cannot fully yet describe that language isn't a matter of learning little building blocks like words and putting, putting them together in some kind of hierarchical structure and then going out and kind of throwing these out to the rest of the world so ideas jump from my mind to yours. Language is a matter of me learning how to coordinate my behavior with all of the other individuals in the world around me and that much of this initial coordination is through glances, through patternings of behavior together, through joint understandings of how the world works, and joint constructions of how we're going to operate in this world together.
PAUL HOFFMAN: Savage-Rumbaugh has her detractors, but she also has her supporters, some of whom have applied her techniques to communications research with humans. For instance, the keyboard technology has provided profoundly mentally retarded kids with a means of communicating. J.J., 18, can't speak, but after a decade of working at the language center with a keyboard like Konzi's, he can finally communicate.
WOMAN: Did you watch TV with--
JJ: (pressing keyboard) Baseball.
WOMAN: Did the Braves win? It was a good game, wasn't it? That's right. I was very glad that they won, very glad. There's going to be more baseball on--
JJ: (pressing keyboard) Baseball on TV--
WOMAN: --tonight. Are you going to watch again? That's right. What time i it going to be on?
JJ: (responding) 8.
WOMAN: Eight o'clock.
PAUL HOFFMAN: Program director Mary Ann Romski.
MARY ANN ROMSKI, Georgia State University: I think that's what's so powerful about it for the children, is that when, for example, JJ able to tell you something through the use of his board and, umm, speak to you that way, that you see something about what he knows and otherwise, you don't have that window. You just think he's a child that has mental retardation and sort of grunts and vocalizes and smiles at you, maybe laughs with you, but you don't now what's really in his mind. But when he uses specific symbols in specific ways, you have a sense of what he knows about his world. And I think that's true about the apes. It gives you a window into their minds that otherwise you wouldn't have.
DUANE RUMBAUGH: And who knows? Maybe someday we will learn how to get Benobos and chimpanzees to learn how to talk and then even the most conservative critic would say, it is language.
MAN TALKING TO CHIMPANZEE: Pambinisha, do you want to wear the monster mask?
SUE SAVAGE-RUMBAUGH: Monster? Oh, she wants to hide.
MAN: Does she? All right.
PAUL HOFFMAN: Ultimately, Dr. Savage-Rumbaugh hopes her research will compel us to rethink our notion of what's uniquely human.
SUE SAVAGE-RUMBAUGH: If we fully accept the implications of this research, it says that we shouldn't be keeping them in zoos. It says that I shouldn't be keeping them in the research lab that I have them in, and it says we're not going to learn anything more about them by doing this, and it does raise a question of the, the properness, the morality of doing it. It is almost as though we realize there's another nation of creatures out there, and we have some obligation to them, just like we have obligations to other nations of human beings, to see that they have a right to live the kinds of lives that they are capable, we now know, of living.
PAUL HOFFMAN: Few scientists question Savage-Rumbaugh's view that chimps deserve more humane treatment. But her conclusions about apes and language continue to generate controversy in the scientific community and to challenge mainstream thinking about what really distinguishes humans from the rest of the animal kingdom.
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