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Talking with Chimps

There has always been much fascination with primates and especially with chimpanzees because they are so similar to ourselves. Many researchers feel that chimps may be so much like humans that they may be able to understand and communicate with us using a language that we could understand. Since we are well aware that a chimp's anatomy renders it virtually impossible to speak a human language, many researchers began to wonder whether it was possible for a chimp to communicate with us in other ways . This idea resulted in using methods from American Sign Language to lexigrams in an attempt to communicate. The question is was one method more effective than another in facilitating communication, and perhaps more importantly, is it possible for a chimpanzee to understand and reproduce, in a none verbal manner, a human language?

In order to establish whether chimpanzees are capable of understanding human language we first must define what human language is. The noted linguist Noam Chomsky offers perhaps the best comprehensive definition of human language. First, he says that human language has structural principles such as grammar or a system of rules and principles that specifies the properties of its expression. Second, human language has various physical mechanisms of which little is known but it does seem clear that "laterization plays a crucial role and that there are special language centers, perhaps linked to the auditory and vocal systems"(Chomsky, 1980). The third quality of human language is its manner of use. Human language is used for expression of thought, for establishing social relationships, for communication of information and for clarifying ideas. Another characteristic of human language is that it has phylogenetic development in the sense that language evolved after humans had separated from the other primates. Therefore language must have had a selective advantage and must coincide with the proliferation of the human species. Finally, human language has been integrated into a system of a cognitive structure.

Having defined what human language is or more precisely what it consists of, it is important to now turn to a few of the many chimp language experiments to see if any of these primates seemed to have understood language in the manner that Chomsky defined it. The first Chimp language experiment ever conducted took place in the 1930's by W.N. and L.A. Kellogg with a 7 1/2 month old chimp named Gua. The Kellogg's compared the chimp's development with that of their newborn son with the intention of determining how much of human language is derived from heredity and how much is derived from education. This experiment only lasted for nine months and at its end it was determined that the chimp could not learn those aspects of language that a human inherently knows (Animal Communications:Primate Studies). This experiment is only worth mentioning because it was the first such experiment of its kind and, due to that fact it had many schematic problems it does not warrant further discussion. The first chimp experiment that warrants real investigation was done by Allen and Beatrice Gardner in the 1960s and was the first to use American Sign Language in primate communication. The Gardner's decided to use a chimpanzee for their language experiment because they felt that the chimpanzee is highly intelligent, and more importantly, a highly social animal. They felt that sociability was a prime factor in the acquisition of language in human beings. After deciding on using a chimpanzee the Gardners struggled over how to go about teaching it human language. They decided that it would be useless to teach the chimp to speak mainly because its vocal apparatus is so different from humans. In addition, chimps tend to make noise only when excited and the Gardners felt that this tendency would not fit their needs very well. They finally decided on American Sign Language or ASL as the mode of communication because it doesn't involve speech and also because it would be fairly easy for a chimp to manipulate its hands in order to form signs. The training of Washoe, the chimp used in the experiment, began when she was 11 months old and lasted 51 months. During this time she acquired 151 signs. It was the Gardners' observation that chimps and humans are very similar in many aspects such as blood chemistry, sensory system, as well as a prolonged dependency of child on mother. It was for these reasons that the Gardners decided that it would be possible to teach a chimp ASL and concluded that a chimp would be very similar to a human child in learning ability. Due to this assumption they treated Washoe as if she was a human child, she had scheduled meals, nap times, bath time etc... The idea was to immerse Washoe in the world of the deaf and ASL and to carry on spontaneous conversations between her and her trainers. One of the first things that the Gardners noticed was that a lot of Washoe's signs seemed to be imitation, much like the way an infant would imitate their parent. For instance, every night before she went to bed Washoe would brush her teeth and the sign "toothbrush" would be signed to her. One day Washoe went into the bathroom and signed "toothbrush" by herself with no provocation. The Gardners feel that this was done for the sole reason of communication, much like the way a small child might communicate to their parent. Perhaps the most significant finding of the Gardners was that it appeared as though Washoe produced her own combinations of words such as "dirty Roger" where dirty is used as an expletive and "water bird" upon seeing a swan on a lake. The Gardners argue that it was highly unlikely that Washoe would be able to combine the right words, in the right context, unless she understood at least some of the rules of human language.

The Gardners are however, quick to point out that many of Washoe's early signs were "acquired by delay imitation of the signing behavior of her human companions but very few if any, of her early signs were introduced by immediate imitation". The most effective way they found to teach the chimp to sign was to form her hand in the shape of the sign and use constant repetition. They are also quick to point out that by the time the project was finished Washoe knew more than 30 signs including object names, using pictures of objects as well as the actual objects. She also had the capability to form sentences with the words that she did know, most of them involving the pronouns "I" and "you". It is clear that the Gardners did indeed feel Washoe could understand some things in ASL even though her vocabulary was quite limited. Unfortunately Washoe was studied for only 51 months so their understanding of her full language development capability was limited by this fact. Herb Terrace was very interested in project Washoe and studied the only two video tapes available of her using ASL. While viewing the film The First Signs of Washoe, Terrace noted that Washoe's utterances either followed or interrupted Gardener's utterances and that Gardner signed the word "time" just before Washoe signed the phrase "time to eat". In the other film Teaching Sign Language to the Chimpanzee: the Gardners claim that Washoe came up with the sign "Baby in My Drink" all on her own when she found a doll in her cup. They maintained that this was a creative process and hence was one of the major developments of human language. After viewing the tape over and over again Terrace concluded that only the words "my drink" were not prompted by the trainer and therefore it is not a spontaneously generated utterance. Terrace concluded that Washoe, on the whole, was merely mimicking her trainer and therefore really did not comprehend the human language or its grammatical rules.

Another method employed in an attempt to teach a chimpanzee human language was employed by Sarah and David Premack in 1966. The chimpanzee that they used was a six year old female named Sarah who was brought to live in a cage at the University of California, and was treated strictly as a laboratory animal. Instead of using ASL the Premacks decide to use plastic chips of various shapes and colors, each representing an English word. Sarah was to place these various chips on a "language board" in order to form sentences. She learned to do this by first seeing a piece of fruit, such as an apple, followed by being shown the plastic chip that represented an apple. Sarah was given the apple to eat if she could pick out the symbol for apple and place it on the language board. After she had mastered this task the same method was employed with common objects and people. The second stage consisted of stringing the symbols together to form such sentences such as /Mary/ + /Apple/ on the board to symbolize "Mary to give an apple". The next step involved putting three symbols together to form such sentences as /Mary/ + /to give/ + /apple/ while the final step consisted of four unit utterances such as /Sarah/ + /to / /give/ + /apple/. The Premacks claim that by the time they had finished working with Sarah she knew 130 signs and could make meaningful sentences of up to eight units long. It is important to point out, however, that at no time did Sarah ask any questions though when alone in her cage Sarah would form the utterances that she had just learned onto her board.

Another method was employed by Duane Rumbaugh in the mid 1970's in which he decided to teach a chimpanzee language by employing symbols. The researcher felt that it was important to eliminate human contact in teaching chimps language. They felt that automation would prevent anyone from cuing the animal and the training could be more efficient and would require less people. A computer would perform certain functions such as dispensing food or displaying slides in response to an operator lightening up the proper symbol.The system that they decided to use would provide 24 hour a day operations that would not require a human operator. The chimp that they worked with was a two year old named Lana. In the lab they built her a room made out of plastic and glass which had two way visual access. Lana was given a keyboard which had keys (or lexigrams) that each represented a word. Outside of Lana's room there was another keyboard that allowed for two way conversation between the chimp and the researcher. Between the two keyboards was a computer that monitored all linguistic events , and was also used to evaluate Lana's use of language and to record all other communications.

Lana was initially taught to use a single key, followed by teaching her how to ask for things such as food or water. Eventually Lana would enter into a conversation without being prompted to do so. It was, however, found that "Lana had been prone to converse whenever she must do so in order to receive something exceptional or whenever something was not in accordance with the routine delivery of food and drink or, in short, when some practical problem arises for her". For her, language is the means to receive something that she desires, and seems to serve no other useful purpose.

There are a few studies going on today that are concerned with teaching a chimpanzee how to communicate by using a human language. Perhaps one of the most interesting is being preformed by Sue Savage-Rumbaugh. Savage-Rumbaugh feels that it is more important to concentrate on the question of whether apes understand the signs they produce, instead of do they have grammatical capabilities. Therefore her studies move away from the design features of language such as productivity and displacement, which were so popular in other studies. Savage-Rumbaugh points out that human languages use symbols, which consist of three components. The first of these is the physical external substance such as a word, "mountain" for example, either written down or spoken with a specific linguistic pattern. Second, there is a relationship between this and a real mountain which is known as a referent because the word refers to it. This means that when the word mountain is mentioned the person conjures up a mental representation of a mountain. Finally, symbols in a language allow us to think about things that are not present, and even about things that do not exist (such as dragons or unicorns, for example).

Savage-Rumbaugh suggests that in all previous primate communication experiments the primates were not using their signs symbolically. She feels that the apes had merely "learned to associate certain behaviors (making or seeing a particular sign) with certain consequences (getting something to eat) -similar to a dog, who upon hearing the word 'walk' knows its going to go for a walk". The previous language communication experiments she feels did not test enough to see if the animal truly had acquired a word. It is obvious that there is no clear answer to the question that posed at the beginning of this paper, namely can a chimp understand and reproduce a human language. Although the verdict is still out on how much a chimp understands of what is being said versus how much it is mimicking its trainer, it does seem very apparent that the chimps do have some skills that we previously did not believe they had. Although they may only use language to get what they want, the point is that they are in fact using a language, even if it is not in the way that a human child might use language. They are not human children so it does not seem logical that they would use language in exactly the same way. Either way it does appear that chimps are capable of understanding human language, to what degree still needs to be determined. It is important to keep in mind as well, that chimps have not had the time, the same time that humans have to evolve the complexities of language, but given enough time they might be able to master the abilities of language, and perhaps even to surpass us.
Thank you very much.