Anthro Notes
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W-~A628 m mm dnthro u notes National Museum of Natural History Newsletter for Teachers vol. 8 no. 3 fall 1986 SPEAKING OF APES: LANGUAGE EXPERIMENTS AND COMMUNICATION AMONG OUR CLOSEST RELATIVES What would other animals tell us and the great apes, many of the about themselves If only they could characteristics once thought to be speak? What could a close relative unique to humankind are being such as the chimpanzee tell us about discovered, albeit in a very limited ourselves and our history? Like Dr. form, in the behavioral repertoires of Doolittle, researchers have long the chimpanzee, gorilla, and orangutan. dreamed of communicating with other species. Over the past years, numerous For instance, it used to be thought experiments have shown that a capacity that only humans used tools. Then Jane for symbolic language is not Goodall at the Gombe Stream Reserve in necessarily the sole preserve of Homo Tanzania electrified the world with the sapiens , and that it may indeed be news that chimpanzees also used possible to have meaningful rudimentary tools in the wild, to fish communication across species for termites and to sponge up water. boundaries. Others have observed chimpanzees elsewhere using rocks as hammers and It has become increasingly clear to anvils to crack open palm nuts. Some anthropologists in the past decade, anthropologists countered that only man that although there are dramatic actually made tools, but, once again, differences between the overall chimpanzees were found to prepare their behavior and lifeways of humans termiting sticks with considerable care and foresight. One captive orangutan speech. As her surrogate mother summed was even taught to chip stone tools. up the experiment in the 1951 book The Clearly, no other animal species Ape in Our House , "We said that if an depends on tools for survival to the ape had proper upbringing, it might extent that the human species does (and learn to speak spontaneously. But we has done probably for millions of were wrong. You can dress an ape in the years) , but it is nonetheless true that finest of finery, buy it a tricycle, at least our closest relatives are and kiss it to death—but it will not capable of tool-using and tool-making learn to talk." behavior that foreshadows that of human beings. Viki's inability to master spoken language was not a training problem, we In the same way, it now appears know now. It has since been demonstra- that the ability to think about and ted that in addition to some differ- refer to things in the abstract, or by ences in their vocal tracts, apes means of symbols, may be due in part to simply lack the special brain connec- a common substrate of intelligence that tions which make human speech possible. we share with the chimpanzee, gorilla, In the 1960's, psychologists began to and orangutan. Although it is not yet realize that language had to be clear whether any of the great apes distinguished from speech when thinking make use of this capacity in the wild, about primate communication abilities. recent experiments in laboratories and Because human language is expressed primate colonies have shown that all through speech, we tend to equate one apes are able to learn symbolic systems with the other, but any formal of communication modeled after human communication system is a language. language. Further, apes can communicate with humans and other apes If chimps cannot speak, perhaps about objects, persons, places, and they can use a different form of activities using these "artificial" language. As a result of more field languages. For those who believed that work among chimpanzees in their natural language and the ability to communicate habitat, some observers noticed that about something other than one's chimpanzees use hand signals in their immediate emotions were the sole natural communications with each other. province of human beings, these Suggesting that chimpanzees might be experiments have provided a fascinating more successful at learning methods of glimpse into the minds of apes and communication that used the perhaps have given us clues about the chimpanzee's native gestural abilities, communicative potentials of our last the Gardners, working at the University common ancestor. of Nevada in the 1960's, taught their chimp infant, Washoe, to make hand The first attempts in the 1940's to signals in ASL (American Sign teach chimpanzees how to speak mimicked Language) . The success the Gardners the way human infants learn language. were able to achieve excited Baby chimpanzees were raised in human anthropologists, psychologists, and homes, by human caretakers, and were linguists everywhere. During her four treated as if they were human. One years of training, Washoe learned 150 such chimpanzee, Viki, was eventually signs, signed them in combinations able to use pictures to ask for objects (though never in such a constant order or activities. On tests of conceptual as to resemble a real sense of syntax), discrimination she was as accurate as and learned some signs that were never similarly aged human children. But taught to her, apparently by imitation Viki was never able to pronounce more and observation alone (such as than three words, even after years of "smoke") . She also invented some signs training and constant exposure to human on her own and adapted others. Washoe's success with sign language symbolic capacity for language. Because was not unique. Over the course of the of these studies' relative openness, last 15 years, similar experiments have they also document the trained animals' been conducted with other common ability to use symbolic communication chimpanzees and with the bonobo (or in innovative and productive ways, such pygmy chimpanzee), the gorilla, and the as to convey spontaneous or novel orangutan as well. Most of the thoughts and desires. Koko, a lowland experiments have focused on sign gorilla who was raised from infancy and language, but such studies are taught ASL by Dr. Francine Patterson, difficult to control scientifically, now has a sign vocabulary of some 500 and utterances must be filmed to be words and recognizes 500 more. This is preserved. Hoping to avoid these the largest vocabulary of any of the methodological problems, some signing apes. Most importantly, Koko experimenters devised artificial uses her abilities to joke with, lie languages, based on plastic tokens or to, and insult her human and animal keyboard symbols, in order to better companions, as well as to perform the control and record the animals' actual more mundane vocabulary exercises and utterances. Sarah, a common comprehension tests, which are chimpanzee, was taught by David and Ann administered to obtain objective Premack to manipulate plastic discs of information about her language skills. various shapes and colors to name and Koko has used sign language to protest ask for objects and to make simple sentences. Another chimpanzee, Lana, at the Yerkes Primate Center, was taught "Yerkish," an artificial language using "lexigrams" (or graphic symbols) on a keyboard connected to a computer. This system had the advantage of eliminating the human trainer, and with it, the possibility that humans were unconsciously cuing the animals to make appropriate responses, a criticism which continues to cloud some of the sign language studies' results. The artificial language systems have also had their own share of critics. With such narrow training, some say, the animals have little opportunity to use language in the important ways in which humans use it, namely to construct a world, to obtain desirables, and to regulate the y//A \imx^j^-jE^miB ' f. behavior of others. "Language" it may be, but it is divorced from the open © social context that makes language a meaningful phenomenon instead of a trivial game. Although the sign language experiments are difficult to conduct, maintain, and to verify by objective means, they still provide us with the most compelling evidence of the apes' to trainers about boring vocabulary- contribute to ape testing performance drills, to ask for a kitten as a pet just as they do to that of human (which she got), and to insult her children. young male gorilla companion Michael ("Michael stupid toilet devil"). Fortunately, the researchers at The Yerkes Center have found ways around To be sure, not all authorities these various methodological impasses. have been willing to accept that the The latest results of the work of Sue behavior being taught and used is truly Savage-Rumbaugh and her colleagues are "language." Before these studies were the most impressive yet. Dr. first undertaken, it was assumed by Savage-Rumbaugh worked for many years many prominent linguists that human training two common chimpanzees, language was so distinct and Sherman and Austin, to use Yerkish. qualitatively different from all other Their training was considered forms of communication that it could successful, but nonetheless the two not be explained as an evolutionary common chimpanzees required intensive development from any more primitive conditioning to first acquire symbols communication system. But the language and then to progress from a simple studies showed that ape language did stage of symbol association to the more share some of the important components abstract representational use of of human communication. Apes could use symbols. In sum, although common a symbolic system of arbitrary chimpanzees clearly can deal with referents, could generalize (that is, symbolic usage on a conceptual level, transfer meaning from one context to they still do not learn language in the another appropriate one, as in the use same way, at the same pace, or with of the word "coke" to mean all sweet anywhere near the same facility as do dark drinks) , and could use signs or human children, even with the kind of symbols to create new words or intensive conditioning that children combinations of words spontaneously in never undergo.