The Ape Within Us

Initial Forays Into Ape Language

Dr. Sue Savage-Rumbaugh

The fascination with the idea that apes might be able to become human if they acquired a human language compelled early students of behavior to try to determine whether or not apes could, in fact, acquire language. In 1909, Lightner Witmer a behavioral psychologist observed that a zoo performing chimpanzee learned to produce the word “mama.” By working with this ape, Witmer found he could easily teach it to produce a “pa” sound. Witmer speculated that psychologists of the future should be able to make far more progress. In 1912, the novel Tarzan of the Apes appeared and the idea that humans might learn to talk to apes, if exposed early in life, began to settle into our national psyche, even though it was understood that the Tarzan story was a myth.

It was into this environment of questions that the study of ape language moved forward. At first, the questions were straight forward — could apes live in a human family and would they adopt human traits, possibly even language? The following article summarizes some of the early studies that attempted to answer that question. Today, however, the questions being faced by the scientists of Great Ape Trust are exceedingly complex.

Early Attempts into Ape Language

Gua: An Experiment In Co-Rearing Human And Ape Infants

Behavioral psychologist Winthrop Kellogg was intrigued by the reports of “wolf children” who, after being raised by wolves from infancy, were said to be unable to learn language, walk bipedally, dress themselves or eat with utensils. In 1931, Kellogg, who was working at the Yerkes Primate Research Center, undertook a nine month experiment to raise his 10-month-old son, Donald, with Gua, a seven-and-one-half month old chimpanzee.

Kellogg was determined to place Gua in a human environment and to treat the ape much as he treated his own son. Kellogg concluded that Gua equaled or surpassed Donald in most developmental landmarks. Not only did Gua acquire many human characteristics, but Donald began acquiring many chimpanzee characteristics. Because Donald’s ability to communicate with chimpanzee vocalizations exceeded Gua’s ability to produce human vocalizations, Donald began to prefer Gua’s communication system. Many people speculated that the abrupt termination of the experiment at nine months resulted from the strong effect Gua exerted on Donald’s development.

According to Benjamin and Bruce (1982), this study “was designed to be the definitive investigation explicating the interaction of hereditary and environment.” As such, it probably succeeded better than any study before its time in demonstrating the limitations heredity placed on an organism regardless of environmental opportunities as well as the developmental gains that could be made in enriched environments. At the end of nine months, Kellogg demonstrated that environment, particularly psychological environment, is necessary for the development of an individual’s inherent abilities. Gua, treated as a human child, behaved like a human child except when the structure of her body and brain prevented her. This being shown, the experiment was discontinued.

Kellogg’s experiment remains the only co-rearing attempt of human and ape infants to have ever been reported. Recent findings, detailing an entirely new way in which certain neural systems in the brains of developing individuals begin to mirror the brains of those around them suggest that the sibling co-rearing variable was probably far more important than even Kellogg himself realized at the time.

Viki: An Experiment In Acquiring Language And Culture

The quest to determine whether an ape could acquire language and culture was furthered by Keith and Cathy Hayes, behavioral psychologists working at the Yerkes Primate Research Center in the late 1950’s. Unlike Kellogg, the Hayes’ had no children and raised Viki, an infant chimpanzee, without siblings.

The original hope was that Viki would learn to speak. However, when it became clear that Viki was showing no spontaneous inclinations at all in that regard, shaping sessions were introduced. During these sessions, Keith Hayes held Viki’s lips in various positions and rewarded her for making implosive breathy sounds at the same moment. Viki gained voluntary control over her ability to produce these sounds, but not over the lip/tongue control to produce interpretable speech. Eventually, Viki began to mold her own sounds by manually controlling her own lip movements instead of allowing someone to do this for her. Through laborious effort, Viki acquired four words — mama, cup, papa and up. The implosive “p” sound in each word was produced in the manner described above. This was not easy to do as it required Viki to utilize her entire body to produce the implosive air burst while coordinating this with her ability to hold her lips closed momentarily to block the air.

Although speech seemed difficult for her, Viki, like Gua, began to understand some spoken language. For example, she would rush to the door when it was announced that the family was about to go for a ride in the car. She was able to assist in dressing herself, to sort objects and photos into categories with very little assistance or training. Unfortunately, Viki died of viral meningitis at the age of seven.

The question of whether or not a chimpanzee with language would also become a cultured being remained unanswered.

Washoe: An Experiment In Acquiring Language And Culture

The first major breakthrough in the quest to understand the limits of chimpanzee mind and the influence of language was made by Beatrix and Allen Gardner. In 1966, the Gardners began the first ape language project to break from the tradition of trying to get apes to speak.

Beatrice’s background in ethology led her to believe that learning followed certain predisposed paths and that no amount of shaping could bring some behaviors into existence. Observing the Hayes’ films revealed that while shaping techniques did not produce speech, they were effective in teaching Viki such things as “touch your nose,” etc. This suggested that shaping the hands of an infant chimpanzee might hold far more potential than techniques for shaping mouth and tongue movements. Thus, the Gardners decided to rear Washoe, a young female chimpanzee, in a homelike environment, but to expose her to hand signs rather than spoken language.

Washoe’s environment was monitored around the clock and notes were made on a wide range of behaviors as well as all signed utterances. All those around Washoe were asked to use signs in every communication and were forbidden to speak in Washoe’s presence.

Unlike the Hayes’, the Gardners did not take Washoe into their home. Washoe stayed in a trailer during the day and slept there alone at night. While the Gardners devoted love and attention to Washoe in their spare time, the task of rearing young Washoe fell to an array of graduate students and short-term caretakers. The decision to provide Washoe with a human world, but not a human family represented a significant departure from the earlier studies.

When the Gardners realized that Washoe was not going to acquire language in a spontaneous fashion, they introduced sign training. This consisted of showing Washoe an object, demonstrating the sign, then taking Washoe’s hands and molding them into the proper hand configuration for the sign. Slowly, the molding was less emphasized until Washoe produced the sign on her own. This procedure resulted in rapid sign acquisition and Washoe quickly surpassed Vickie’s attainment of four spoken utterances.

The Gardners assumed the ability to produce a sign implied the ability to comprehend what others intended with the use of a sign. When it was revealed that Washoe had acquired 30 signs and was rapidly on her way to learning many more, a languaged ape, it seemed, had finally arrived.

The Gardners’ success, achieved by altering the paradigm from spoken words to signs, shocked the established academic world. Suddenly there arose a great interest in determining whether Washoe was a “genius” or whether this ability could present itself in other apes.