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Home , Ape, Chantek, Gorilla, Ham (chimpanzee), Koko (gorilla), Lana (chimpanzee)

CurrsmtCmmments” EUGENE GARFIELD INSTITUTE FOR SCIENTIFIC INFORMATION* 3501 MARK ET ST., PHI LAOELPHIA, PA 19104

When the Speak, Lin@sts Listen. I Part 2. What the Critics Say Number 32 August 12, 1985

Last week, we discussed the projects and function of the symbols they use. designed to teach apes a means of com- Rather, the critics suggest that the ani- munication comparable to lan- mals are imitating the trainers or that guage. 1 These projects, which began they are conditioned to respond in the about 20 years ago, were designed to test appropriate manner. Critics afso suggest the linguistic potential of our closest rel- that the apes trained to use artificial lan- atives in the world—the great guages rely on rote memorization rather apes, including the , , than knowledge of syntactic rules in for- and . In the earliest project, mulating word sequences. In the case of researchers taught a chimpanzee to use ASL-trained apes, some critics say re- American (ASL), a ges- searchers may be interpreting too much tural form of used by from the ’ responses, identifying deaf people in . In later as ASL movements that are not projects, were taught arti- well-formed ASL words. Others suggest ficial using plastic symbols or the animals may receive inadvertent cu- a computer keyboard. Each research ing from their trainers. group published data describing the re- In addition to all the controversy sur- markable similarities between the lin- rounding the methods and interpreta- guistic skill of their chimpanzee and - tions of these studies, one of the major ly language development in human problems in thk field is the lack of a stan- children. However, shortly after this re- dard definition for human language. If search appeared, questions arose con- we can’t describe language by a well-de- cerning the methodology and interpreta- fined set of criteria, it is difficult to de- tion of these studies. Let’s now review cide whether another is using it. the controversy surrounding the claims Until recently, we assumed that that apes are able to use a rudimentary were the only species to use language, form of human language. And is the and, therefore, we had no need to define comparison between and child lan- it precisely. In fact, Margaret Atherton guage a valid one? and Robert Schwartz, Department of Phdosophy, University of Wisconsin- Mdwaukee, noted that language is close- What the Crftfes Say ly tied to our concept and definition of Criticism of the ape language studtes human inteUlgenee and that as long as encompasses interpretive as well is uniquely human we can be- methodologic issues. Many critics feel lieve human mentality is unique and spe- that the ape language researchers have cial.z However, anthropologists Horst not provided sufficient evidence to show D. Steklis, Rutgers University, New that the apes comprehend the Brunswick, New Jersey, and J.

302 Raleigh, Brentwood Veterans Adminis- versity of Nevada, Reno, suggest that in tration and Neuropsychlatric Institute, the arttlcial language experiments con- University of California, Los Angeles, ducted by psychologist David Premack note that both behavioral and neurologi- at the University of Pennsylvania and by cal research support the idea of shared Duane M. Rumbaugh working at the cognitive features between great apes Yerkes Regional Research Cen- and humans, 3 Therefore, it should not ter at Emory University and Georgia be surprising that the great apes possess State University, , the chimpan- at least rudimentary language abilities, zees could perform the tasks required of The definition of language and the them on the basis of learning sets and uniqueness of human mental abilities be- rote memory.b In return, Rumbaugh and came an important issue with the first Sue Savage-Rumbaugh, Yerkes Region- words of , an AS1.Arained chim- al Primate Research Center and Georgia panzee. However, the claims that ape State University, state that the Gard- language researchers make for their ani- ners’ Washoe project failed to demon- mals are questioned not only by lin- strate that ASL signs, when used by a guists, but by the ape language research- chimpanzee, are functionally equivalent ers themselves. to the words used by humans. They also suggest that a series of ASL signs formed IS ItLanguage? by a chimpanzee is nothing more than the animal producing a group of “appro- The major question raised by the ape priate” responses, or signs, and not rudk language studies is whether the newly mentary sentences as the Gardners and found communicative abilities of these Francine G. Patterson, who worked apes can be considered language. Noted with the ASL-trained gorilla , linguist , Massachusetts have suggested.7 Institute of , Cambridge, Moreover, psychologist Herb S. Ter- suggested that human language is ac- race and colleagues, Columbia Universi- quired effortlessly and without training.d ty, New York, concluded from their ape However, Catherine E. Snow, Institute language study, which was designed to for General , University of replicate the Gardners’ work, that the Amsterdam, the Netherlands, noted that chimpanzee can learn that particular is the result of in- symbols are appropriate to particular sit- teraction between the mother and chdd uations.a The function of the ASL sym- beginning in eariy infancy and involves bols used by Terrace’s chimpanzee, teaching on the mother’s parts Mothers Nim, was not so much to identify things speaking to their children limit the or convey information but to satisfy the semantic content, but not the , trainer’s requirement that the chim- to what the child can understand and re- panzee use the proper symbol to obtain a produce. The ape language experiments reward.g also require extensive training of the research subjects. Spontarteity Ape language researchers seem to be the most severe critics of each other’s One quality that is generally agreed to work. Since three different language sys- be characteristic of human language is tems have been used to train the apes, spontaneity. Terrace and colleagues re- the various researchers d]sagree as to ported that Nim’s language performance whether the others are indeed teachhg was almost entirely prompted by the and testing their animals in the best way. trainers or imitative of their signs.s Imi- For example, psychologists R. Allen tative signs are those that are repeated Gardner and Beatrix T. Gardner, Uni- immediately after the trainer makes the

303 sign. Prompted signs, on the other , tions, Miles found that 37 percent of use only part of the sign made by the ’s utterances were spontane- trainer. By observing films of Washoe ous. 13 Her reanalysis of videotapes of and Koko signing, Terrace and col- Nim’s signs found that 8 percent were leagues reached a similar conclusion re- spontaneous. As Sanders suggested, the garding the lack of spontaneous signing. pattern of the ape’s signing is sensitive to However, in a recent book, linguist the setting, goals, and behavior of the Philip Lieberman, Brown University, trainer. Spontaneity and are Providence, Rhode Island, points out related to the environment as well as to that Terrace used very stringent crite- the animal. 12 ria.g Terrace considered signing sponta- Rumbaugh and T.V. Gill, then his neous only if it was not preceded by a graduate student, noted that their chim- teacher’s signing.g Lieberman noted that panzee, , seemed to lack motiva- these criteria are much more stringent tion to use language, requesting the than those used by child language re- names of things only when they were searchers in analyzing spontaneous ut- food items. “She never ‘discussed spon- terances. He points out that, according taneously the attributes of things in her to the criteria used by Terrace, children world.” 14 According to Savage-Rum- between the ages of one and two years baugh and colleagues, both Washoe and almost never produce spontaneous ut- Lana used their language sk~s to “con- terances.g trol and regulate the behavior of their Patterson, then of Stanford Universi- human experimenters.”ls Mark S. Sei- ty, California, d~putes Terrace’s asser- denberg, Center for the Study of Read- tions about the spontaneity of Koko’s ut- ing, University of Illhois at Urbana- terances. She claims that 41 percent of Champaign, and Laura A. Petitto, De- Koko’s signs are spontaneous and 11 partment of Human Relations, Harvard percent imitative, 10in contrast to the 28 University Graduate School of Educa- percent spontaneous utterance figure tion, Cambridge, afso suggest that the Terrace and coUeagues calculated for apes have not learned the meanings or Koko. ]1 Patterson, as well as the Gard- grammatical functions of signs; rather ners, notes that films of ape-trainer in- they have learned that signing behavior teractions made under classroom drill is very important to the researchers and conditions are not representative of the can be used to obtain food, Seidenberg everyday that is necessary for and Petitto compare th~ behavior with comparison with chdd language. that of a child who learns an obscene Psychologist Richard J. Sanders, Uni- word. The child knows that repeating versit y of North Caroliia, Wilmington, a this word will produce a certain response former graduate student in Terrace’s in the adult. In essence the chtid under- laboratory, suggested that the method of stands the consequence of saying the testing influences the degree of imitation word but not the meaning of the word. lb by the ape. 12 In fact, in a study of lan- Another indication that the apes do guage acquisition in the ASL-trained not understand the symbolic signifi- orangutan Chantek, anthropologist H. cance of their communication is that Lyn Males, Department of Sociology and they do not appear to engage in conver- Anthropology, University of Tennessee, sational tum-takmg, Language users Chattanooga, used Terrace’s criteria for take turns, functioning both as produc- analyzing the spontaneity of utterances. ers and recipients of . However, the recording was done in a r&race concluded from his studies of relaxed environment where the animal Nim that his signing bore only a superfi- was allowed to move freely and was not cial resemblance to a chdd’s conversa- pressured to sign. Under these condi- ~ons with its parents. While the child

304 frequently initiates conversation, only stitute, Kyoto University, Inuyama, Ja- 12 percent of Nlm’s utterances were , examined the interaction between spontaneous. 17Thomas E. Van Cantfort receptive and productive language and James B. Rimpau, Department of skills.zz Kojima used a language training Psychology, University of Nevada, system similar to the one used by Rum- Reno, suggested that Terrace and col- baugh and Gill. 14The researcher found leagues misread the overlapping be- that in the chmpanzee , productive tween the first sign of the chimpanzee’s language skills, such as naming, and re- reply and the last sign of the trainer as an ceptive skills, such as understand~ng, de- interruption. 18 In ASL an overlap in veloped independently of each other. signing between two fluent signers is And, although these two language common. In fact, Miles found an equal modes were independent in early lan- number of interruptions between the guage acquisition, Kojirna found that in caretaker and Chantek. 13 later stages they helped one another. Carolyn A. Ristau, Department of That is, receptive language skills helped Animal Behavior, The Rockefeller Uni- in the acquisition of productive skills versity, New York, and Donald Rob- and vice versa, implying that the name bins, Division of Social Sciences, Ford- became symbolic of the object in the University at Lincoln Center, New chmpanzee’s mind. York, suggest that learning of artificial languages by apes is more properly com- pared with the learning of by hearing-impaired children than with the development of in The two basic components of English normal chddren. However, Ristau and are the word and the sentence. Each Robbins also report that data on the de- word has a separate meaning; a sentence velopment of sign language use in chil- expresses specflc meaning by combin- dren are sparse. 19 ing words in a particular . The meanings of sentences, unliie words, comprehension cannot be learned one by one. When Many of the ape language critics re- learning English, children master gram- port that too much emphasis has been matical (syntactical) rules that allow placed on language production and not them to express a thought by arranging enough on comprehension, For exam- words in a particular order. However, ple, Seidenberg and Petitto claim that Edward S. Klima, University of Califor- none of the projects included formal nia, La Jolla, and Ursula Beflugi, Salk In- tests of word comprehension and that stitute for Biological Studies, San Diego, all of the studies relied largely on anec- California, indicate that sign language dotal evidence. lb However, the Gard- uses and markers, rather than ners examined Washoe’s response to Wh word order, to relate meaning.m John questions, such as “Who,” “What,” Limber, Department of Psychology, “Where,” and “Whose.” Washoe’s re- University of New Hampshire, Durham, sponse was appropriate 84 percent of the noted that too much ape language re- time, an indication that she understood search focuses on the word rather than the meaning of the questions.zo How- the sentence and indicated that word ever, Rumbaugh indicated that although production is not sufficient evidence to Washoe’s responses were generally cor- conclude that the animal is using lan- rect, the Gardners judged Washoe’s guage.zd answers to be correct as long as they Several ape language researchers were in the right category of response.2 1 claim their animafs create elementary More recent research by psychologist sentences. Terrace and colleagues sug- Tetsuya Kojima, Primate Research In- gest that the sequences of signs pro-

305 duced by apes using ASL may at first after the initial request and linguistic resemble the early multiword sequences spectilcation is omitted, while the name of chddren. However, they maintain of the food is repeated. Savage-Rum- that alternative explanations of the apes’ baugh’s chimpanzees, Sherman and word combinations must be ruled out Austin, used words to clarify ambiguity before we conclude that the learning rather than to comment on the obvious. processes are the same in apes and chfi- And depending on how ambiguous the dren. One alternative explanation is that situation was, the more likely they were the apes are imitating the trainers’ sign to use more than one word.zb sequences, s Anthropologist Jane H. Other criticisms were directed toward Hill, Wayne State University, Detroit, the sign-language studies. Interpreta- Michigan, noted that chimpanzees can tions of novel word combinations were learn to put things in any order the said to be too elaborate. One of the trainer instructs, but little evidence ex- most-cited examples is Washoe’s signing ists that these order requirements serve “Water bird on first seeing a swan on a the same syntactic function that they pond.zq Ristau and Robbins, among serve in human language. zs This is espe- others, question Washoe’s intent. Was cially true for the artificial language ex- she actually calling the bird a water bird periments. or was she indicating that the bird was on In fact, Patricia M. Greenfield, De- water? 19 However, anthropologist Su- partment of Psychology, University of zanne Chevalier-Skolnikoff, University California, Los Angeles, and Savage- of California, San Francisco, suggests Rumbaugh suggest that since there is in- that some novel sign combinations made creasing skepticism about the capacity by the gorilla Koko cannot be explained of the chimpanzee for syntactic lan- this way. For example, Patterson report- guage, communication, rather than for- ed that Koko signed “White tiger” for a mal linguistic structure, may be the zebra. That this would refer to white and place to look for chdd-chimpanzee par- tiger does not seem a likely explanation. allels.zh Chevalier-Skolnikoff further suggests A review of data from the Washoe that this utterance may even represent a project in 1974 led psychologist David grammatical phrase, since white alone is McNeill, University of Chicago, to con- not cent extually relevant.~ In fact, clude that Washoe imposed her own for- Roger S. Fouts, Department of Psychol- mula on the sentence structure she ob- ogy, University of Oklahoma, Nor- served in her trainer’s signs.z~ And the man,zq and Terrace and colleagues also order of words in her sentences probably presented evidence of grammatical depended on the prominence of the structure in the two- and three-sign ut- things she was discussing. Greenfield terances of their chnpanzees. and Savage-Rumbaugh suggest that the pattern of chimpanzee word use does Cufng not imply that utterances beyond one word are memorized or . 26 Criticism of the methods used in ape They found that the chimpanzees using language experiments centers on the computer-controlled language have a possibility that trainers inadvertently tendency to mention the variable while give cues or hints to the animal through a leaving the constant or redundant un- process known as the phe- said, Greenfield and Patricia G. Zukow, nomenon. Thii phenomenon was first University of California, Los Angeles, recognized in the early part of this cen- reported that this is also true for chil- tury, in Germany, in a very early case of dren.m For example, in food requests, animal “learning. ” A home named Hans, the of the food is presumed belonging to an animal trainer named

306 von Osten, seemed able to count and could communicate information; that is, solve arithmetic problems. While most she could tell the trainers things they observers were amazed, some remained didn’t know—something that Clever skeptical. One of those skeptics was psy- Hans could not do. chologist Oscar Pfungst at the University Although the possibility of inadver- of Berlin, who determined that the horse tent cuing exists, Savage-Rumbaugh and perceived von Osten’s involuntary head colleagues suggest that, whether or not movements when the number of hoof- the apes understand the symbolic mean- taps corresponded with the correct ing of their words, “their behaviors are answer. On seeing this unconscious cue, too complex to be controlled by a simple the horse stopped tapping.sl The animal ‘go’ or ‘no go’ cue.”sb From an analysis of was skilled in perceiving human body the Clever Hans phenomenon, Cheval- language, not in arithmetic. ier-Skolnikoff concluded that the ape’s Linguists Jean Umiker-Sebeok and use of ASL requires more advanced cog- Thomas A. Sebeok, Indiana University, nitive abilities than could be accounted Bloomington, believe that almost all of for by cuing alone.~ In fact, Miles re- the ape language projects present ample ported that the signing orangutan in her opportunity for Clever Hans cuing. Pre- laboratory attempts to communicate mack tried to eliminate the Clever Hans with nonsigning humans from whom he effect by using a trainer unfamiliar with could not be receiving cues. 1s the symbolic language used by his chim- In an analysis of the data from the panzee, . Under these condhions LANA project, psychologists Claudia R. there was a decrease in the animal’s ac- Thompson and Russell M. Church, curacy, which Umiker-Sebeok and Se- Brown University, concluded that beok note is what one might expect if the Lana’s behavior is due to paired associa- chimpanzee was searching for cues from tion learning and conditional discrimina- the experimenter.sz Dalbir Bindra, De- tion learning. In paired association partment of Psychology, McGill Univer- learning, the animal couples a symbol sity, Montreal, Quebec, , sug- with an object or person. In conditional gests that the Clever Hans phenomenon discrimination learning, the animal may even play a role in the assessment of selects a proper sequence of words to a child’s language abifities.ss Despite the form a sentence based on situational evidence that cuing may play a role in cues.37 However, James L. Pate, hn- ape language acquisition, Premack con- guage Research Center, Georgia State cluded that while approximately 10 per- University, and Rumbaugh indicated cent of Sarahs performance might be at- that Lana’s language was more complex tributable to cuing, her performance than a simple discriminative learning was still above what one would expect if model would allow.ss social cues were the only source of her Robert Epstein and Robert P. Lanza, knowledge.sq along with B.F. Skinner, Department of The Clever Hans effect can be elimi- Psychology and Social Relations, Har- nated by using a double-blind procedure vard University, claim to have taught such as the one used by the Gardners in two pigeons to communicate informa- testing Washoe’s vocabulary. This pro- tion in a manner similar to that of Sher- cedure required that the people adminis- man and Austin. Epstein and colleagues tering and scoring the vocabulary tests suggested that these communication be blind to the correct answer. Washoe’s skills in the pigeons were a conditioning responses were scored by two indepen- effect and that a similar explanation can dent observers who could not see the be given for the skills acquired by Sher- test slides.ss Results from these vocabu- man and Austin.sg Savage-Rumbaugh lary tests demonstrate that Washoe and Rumbaugh, however, note that the

307 Epstein experiment cannot be compared language impairment.qs Robert L. Ful- with their work with Sherman and Aus- wiler and Fouts, then at the University of tin since, unlike the two chnpanzees, Oklahoma, Norman, reported that ASL neither of the pigeons was taught the ref- training facilitated in an autistic erential nature of the symbols. The boy with auditory-visual association chimpanzees used symbols to mediate problems.~ requests and select and give food. ~ The The difficulty that comparative psy- pigeons, on the other hand, were re- chologists and linguists have in deciding warded with a specflc food, not a selec- whether apes are indeed using language tion they chose through the use of sym- is derived from an inability to determine bols. which aspects of human communication define language. The lack of a clear defi- nition for language hinders us in deter- conclusions mining what is linguistic and what is not. This is especially true when we look at Part of the problem with ape language children’s language. The question, then, experiments and the data analysis is that of whether apes learn language is not there are changing criteria for language answered, and according to Herbert F. acquisition. When the apes are shown to W. Stahlke, Department of English, meet one set of criteria, more demand- Georgia State University, more research ing ones are devised. ThM makes one will be needed before a definitive con- wonder whether anthropocentrism plays clusion can be drawn .45 a role in the acceptance of this research. Despite the controversies, the ape lan- How much resistance exists to the notion guage projects have made a major im- that something besides a human can ide- pact on studies of communication, lan- ate and “speak”? Part of the problem guage learning, and cognition. In partic- with this research is derived from the ular, these studies have altered our view fact that language has not been properly of the great apes and the relationship defined. However, Ristau and Robbins between apes and humans. Psycholo- suggest that these changing criteria for gist Stephen Walker, Birkbeck College, ape language are necessary until human University of London, noted that it language is better understood. 19 would be mysterious if the functions of In the meantime, the chimpanzee lan- the human brain were unrelated to those guage experiments have been useful in a of structurally similar animal brains.~ In different way. The procedures and com- fact, Terrace recently noted that al- puterized keyboard used by Rumbaugh though there is controversy in the degree and colleagues to teach language to of overlap, apes and human beings are Lana have been used with retarded chil- more similar than any other two species, dren who could not speak. Mary A. especially with respect to their ability to Romski and colleagues, Yerkes Region- learn arbitrary rules in the use of sym- al Primate Research Center and Lan- bols.4T Human language abihties, then, guage Research Center, Georgia State are most Iiiely derived from behavioral University, reported that five severely abilities that are continuous with those retarded, nonspeaking teenagers were of the great apes and are not completely taught language skills with the computer separate and new functions. keyboard.dl One year later, four of these subjects continue to communicate with teachers and unit staff in their institu- ● ☛☛☛☛☛ tion.dz Premack also used his artificial language to teach communication skills My thanks to Linda LaRue for her to an autistic child and to patients with help in the preparation of this essay.

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“We all thought he’d stop at ‘Give apple’ and ‘Put box on table!’”

REFERENCES

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