Are Those Apes Really Talking?

Skeptics say it is mostly a lot of monkey shines

Laura, the teacher, and her young pupil are romping playfully on the lawn in front of their classroom:

Pupil (rolling on ground): You tickle me.

Laura: Where?

Pupil (pointing to leg): Here.

Laura (after tickling him): Now you tickle me.

Pupil (tickling her): Me tickle Laura.

This dialogue between Laura and her charge might not seem unusual, except for one thing: the pupil was not a human child but a young chimpanzee named Nim. Like several others of his primate kin, Nim had been taught to communicate with humans in American Sign Language, a system of hand gestures developed for the deaf.* He eventually learned to make and recognize 125 signs. But the frisky little chimp and other apes who have received such "language" instruction are now the center of a raging academic storm. The issue: can apes really master the essence of human language--the creation of sentences?

A few years ago, the answer might have been an unequivocal yes. After all, Psychologists Allen and Beatrice Gardner of the University of Nevada had managed in the late 1960s to teach the chimp Washoe to use 132 signs; the precocious animal was even credited with having invented a phrase of her own, water bird for swan. About the same time, David Premack, of the University of California at Santa Barbara, using plastic symbols of different shapes and colors to represent words, taught his prize pupil, Sarah, some 130 words and reported that she had also mastered some phrases. At the Yerkes Regional Primate Research Center in Atlanta, the husband-wife team of Duane Rumbaugh of Georgia State University and Susan Savage-Rumbaugh, employing a language of their own invention, called Yerkish (its symbols are projected onto a screen when an ape presses the appropriately marked key on a console), even got two chimpanzees to communicate with each other in this artificial "tongue."

Perhaps the most impressive claims came from Francine Patterson, a psychologist at Stanford, who said she had managed to teach a hulking female gorilla named Koko more than 400 signs. According to Patterson, the gifted ape then proceeded to higher linguistic levels by using word combinations to insult her trainers (You nut), compose rhymes (bear hair, squash wash) and invent metaphors (eye hat for mask, finger bracelet for ring).

Though a few experts expressed skepticism, these claims of the apes' linguistic ability were widely accepted during the 1970s. But now many scientists are beginning to have second thoughts. They suggest that much of what the animals are doing is merely mimicking their teachers and that they have no comprehension of syntax. What is more, they say, the primate experimenters are probably so eager to prove their case that they often provide inadvertent cues to the animals, who quickly realize which "right" answer will bring them some goody. In short, the skeptics raise the possibility that the apes have been making monkeys out of their human mentors.

No one has done more to stir doubts than Columbia University Psychologist Herbert Terrace in his work with little Nim (full name: Nim Chimpsky, a play on the name of Linguist Noam Chomsky of the Massachusetts Institute of Technology, a staunch proponent of the idea that language ability is biologically unique to humans). The object of Terrace's experiment was to prove Chomsky wrong --to show that creatures other than man could, indeed, conquer syntax and link words into sentences, however simple.

Toward that goal, Terrace, with Laura Petitto, a student assistant, and other trainers, put Nim through 44 months of intensive sign-language drill, while treating him much as they would a child. In some ways the chimp was an apt student, learning, for example, to "sign" dirty when he wanted to use the potty or drink when he spotted someone sipping from a Thermos. Nonetheless, Nim never mastered even the rudiments of grammar or sentence construction. His speech, unlike that of children, did not grow in complexity. Nor did it show much spontaneity; 88% of the time he "talked" only in response to specific questions from the teacher.

Armed with his new insights, Terrace began reviewing the reports and video tapes of other experimenters. Careful study of the record showed the same patterns with other apes that Terrace had noted in the work with Nim. There were rarely any "spontaneous" utterances, and what had seemed at first glance to be original sentences now emerged as responses to questions, imitations of signs made by the teacher, or as rote-like repetitions of memorized combinations. For instance, when Lana, a chimp at Yerkes, said Pleas machine give apple, the first three words seemed to mean nothing more to her than a mechanical prelude to obtaining something she wanted. Says Terrace in his 1979 book Nim (Knopf; $15): "The closer I looked, the more I regarded the many reported instances of language as elaborate tricks [by the apes] for obtaining rewards."

An equally serious criticism has been made by Linguist Thomas Sebeok and his wife. Anthropologist Donna Jen Umiker-Sebeok, both at Indiana University. In the introduction to a collection of reports and essays on primate language experiments to be published this month under the title Speaking of Apes (Plenum: $37,50), they maintain that much of what passes for language skill in apes can be explained by the "Clever Hans effect"--a phenomenon named for a turn-of-the-century German circus horse that astounded audiences by tapping out with his hoofs the correct answers to complex mathematical and verbal problems. In fact, as a German psychologist finally discerned, Clever Hans was picking up unintentional cues--changes in facial expression, breathing patterns and even eye-pupil size--from his questioner telling him when and how many times to stomp (or, more precisely, when to stop stomping).

Part of the talking-ape lore may come from the subjectivity of researchers. The Sebeoks note that when Koko is asked to give the sign for drink and makes the proper gesture but touches her ear instead of her mouth, Psychologist Patterson assumes not that the gorilla has made a mistake but that it is joking. If Koko smiles when asked to frown, she is displaying a "grasp of opposites." Say the Sebeoks: "Real breakthroughs in man-ape communication are the stuff of fiction."

Such words touched off angry responses. The Gardners, incensed by Terrace's "weasel talk" and "innuendo," considered suing him. Patterson accused Terrace of "rather muddleheaded methodology." But some of the other researchers are taking a long, hard look at their own work. Premack, now at the University of Pennsylvania, thinks that Terrace's tactic of trying to treat Nim like a human baby was "silly and ill-advised," but he agrees that animals are incapable of spontaneous conversation. The Rumbaughs maintain that their more recent experiments preclude the possibility of trainers giving cues, consciously or sub consciously, to the subjects, but they have their own reservations about the linguistic ability of apes. Acknowledges Duane Rumbaugh: "There is no solid evidence to date that would indicate that the ape is ca pable of using syntax with competence."

As for the man in whose honor Nim was named, he has no doubts. Says Noam Chomsky: "It's about as likely that an ape will prove to have a language ability as that there is an island somewhere with a species of flightless birds waiting for hu man beings to teach them to fly."

* Nonvocal communication is necessary in experiments with apes because their vocal apparatus cannot produce the wide range of sounds that characterizes a spoken language.

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