Kanzi: The Ape at the Brink of the Human Mind (28 page)

Matata’s breeding sojourn was successful and we were pleased to find that she would soon return to the laboratory, pregnant. Despite the joy that another bonobo would bring, however, we wondered if Kanzi would continue to use the keyboard when Matata returned. After all, he had rarely used it before she left. Maybe he would simply want to stay with her again and the importance of his “human friends” would fade into the background. We talked endlessly about what should be done. Some suggested that we should not let Kanzi rejoin Matata, for fear we would never learn what he might be capable of communicating. Keeping a young bonobo away from his mother, when both lived in the same laboratory, seemed to me to be an impossible feat, as well as an unbearable cruelty for the sake of science. We reached a compromise in which Kanzi would be allowed to interact with Matata through the bars of a cage for the first few days. We would then evaluate how we should proceed, based on Kanzi’s interest in continuing to communicate.

Matata arrived at the center one day in September, drugged, while Kanzi was in the forest. I stayed with her in the colony room as she came out of the anesthesia. She was delighted to see me, and vocalized happily when she heard Sherman and Austin’s calls from nearby. Eventually, Kanzi returned, hot and tired after a long day in the forest. I sat down with him and told him there was a
surprise
in the colony room. He began to vocalize in the way he does when expecting a favored food—“eeeh . . . eeeh . . . eeeh.” I said,
No food surprise. Matata surprise; Matata in colony room
. He looked stunned, stared at me intently, and then ran to the colony room door, gesturing urgently for me to open it. When mother and son saw each other, they emitted earsplitting shrieks of excitement and joy and rushed to the wire that separated them. They both pushed their hands through the wire, to touch the other as best they could.

Witnessing this display of emotion, I hadn’t the heart to keep them apart any longer, and opened the connecting door. Kanzi leapt into Matata’s arms, and they screamed and hugged for fully five minutes, and then stepped back to gaze at each other in happiness. They then played like children, laughing all the time as only bonobos can. The laughter of a bonobo sounds like the laughter of someone who has laughed so hard that he has run out of air but can’t stop laughing anyway. Eventually, exhausted, Kanzi and Matata quieted down and began tenderly grooming each other. How could anyone have contemplated not allowing them to be together? If we’ve lost him back to the world of bonobos, so be it, I thought to myself.

Just then, Kanzi gestured for the keyboard and indicated
open
. I opened the cage door and went in. Kanzi climbed on my shoulders and gestured for me to go through the door. I was shocked. Surely he will change his mind as soon as we leave Matata, I thought. But he didn’t. We got Matata some bananas and juice, she vocalized with contentment, and Kanzi looked at me and said,
childside
. Off we went, to see who was still there at the end of the day, something Kanzi often liked to do. All our concern had been for nothing. Kanzi had elected to be with Matata and also with
Homo sapiens;
he was to negotiate two worlds.

For seventeen months we kept a complete record of Kanzi’s utterances, either directly on the computer when he was indoors, or manually while outdoors. By the end of the period, Kanzi had a vocabulary of about fifty symbols. Within a month of separation from Matata, he was already producing combinations of words, and he continued to do so throughout the seventeen-month period of our first report. Other apes had also produced combinations, but Kanzi’s were different in that they reflected a competence born of comprehension, rather than a need to form longer symbol groups to answer questions, as had been the case with other apes. Nearly all (more than 90 percent) of Kanzi’s multiword utterances were spontaneous; that is, they were not
responses to teachers’ requests or imitations of teachers’ utterances. By contrast, Terrace found exactly the opposite pattern in his chimpanzee, Nim. Three-quarters of Nim’s multiword utterances followed something a teacher said. Spontaneity of utterances, rather than their frequency, is a critical aspect of language use, for it is the spontaneous utterances that tell us something about what another party is thinking. Utterances that are prodded out of an ape in response to questions such as
Who Nim hug
—while Nim is already hugging someone named Laura—do not really provide the listener with new information, meaning information that is not already self-evident in the situation.

Kanzi, however, formed spontaneous utterances such as
Matata grouproom tickle
to ask that his mother be permitted to join in a game of tickle in the group room. This happened on one occasion shortly after Matata had vocalized to him. Since Matata typically did not join us in the grouproom play sessions, this request on Kanzi’s part completely surprised us. Perhaps Kanzi knew from sounds that Matata was making that she wished to join us and thus sought to tell us about her wishes. We cannot know for certain; however, we do know that we did not prod this utterance from Kanzi, nor would we have considered bringing Matata into the group room were it not for Kanzi’s communication. Many of Kanzi’s multiword utterances had this character of novelty and functioned to suggest completely new actions and alternatives to our normal ways of doing things.

It was also the case that as Kanzi added more elements to his utterances, the information content increased. For instance, one of Kanzi’s multiword combinations was
ice water go
(with
go
indicated by a gesture), by which he was asking someone to get some ice water for him. A combination such as
play me Nim play
is typical of Nim’s utterances, which contain a great deal of redundancy. Nim may have been more loquacious than Kanzi, but what Kanzi was producing was more like language.

Of Kanzi’s three-item utterances, the most interesting—and significant—were those in which he indicated someone other than himself as the agent or recipient of an action. Most of his three-item combinations involved the initiation of play, such as grab, chase, and tickle. Some of these games involved
Kanzi directly, but others were intended for his teachers. For instance, Kanzi might indicate
grab chase
at the keyboard, and then take one person’s hand and push it toward a second person: the chaser and the chasee. Statements of this sort were Kanzi’s inventions, as none of us suggested we play with each other, leaving Kanzi as spectator. Compared with food requests or requests to be tickled, where the chimpanzee is always the recipient of the action, statements initiating action between two other individuals is complex. As my colleagues and I observed in a paper describing these utterances: “Clearly, prior to the emergence of syntax must be the emergence of the concept that one can request that A act on B, where the speaker is neither A nor B.”
³
The fact that Kanzi mastered this betrays a real sense of self and of others.

We tested Kanzi’s language competence in many ways throughout the seventeen-month period, and one significant feature that emerged was that his comprehension of symbols consistently preceded his use of them. This is the human pattern of language acquisition, and the opposite of how we had concluded from our previous work that apes learned. Moreover, we formed a steadily growing conviction that Kanzi also had a good comprehension of spoken words. This is a difficult issue, one fraught with strongly held beliefs and little scientific data. Many investigators have assumed that apes easily come to understand English, a view held by Charles Darwin. Referring to other animals, too, he wrote in 1871: “[T]hat which distinguishes man from the lower animals is not the understanding of articulate sounds, for, as every one knows, dogs understand many words and sentences.”
⁴

So strong is the impression that Sherman and Austin can comprehend spoken English—and, perhaps too, so strong is the urge to believe it—that visitors to the Language Research Center have often refused to accept our explanation of how they appear to do so. Even when we point out that careful tests, which eliminate contextual information, have demonstrated they do not really have the level of comprehension that appearances suggest, these visitors still choose to believe the chimps can understand the spoken word.

Apes are so aware of, and competent in interpreting nonverbal
aspects of, communication that they often infer a speaker’s intent while not truly understanding the words. If you watch a soap opera on television with the sound turned off, you will gain a sense of the kind and breadth of information that can be conveyed without language proper—it is rather extensive. The ability to “read” information into the situation from a variety of sources, including gestures, glances, actions, intonation, and knowledge of similar previous situations, is highly developed in apes. It is this capacity to read the “meaning” inherent in a given situation that often convinces people that apes are understanding language, for we humans focus so exclusively on language, once it is learned, that we are often unaware of the other channels through which we are gaining information.

When we conducted tests on Austin and Sherman that eliminated contextual information, forcing them to respond to the auditory stimulus alone, their answers were clearly random guesses. In these tests, Sherman and Austin were presented with words that they knew well as lexigrams and were asked to select a matching photo whenever they heard the word. They did well whenever they saw a lexigram, but not when they heard the speech. We could therefore be certain that they understood what they were being asked to do. Often, when they heard only a word, they even gestured to the keyboard, asking me to “say” the word in lexigrams so that they could find the correct picture.

These findings are in accord with observations made of chimps reared in home environments earlier this century, by Louise and Winthrop Kellogg in the 1930s and Catherine and Keith Hayes in the 1940s. The chimps, Viki and Gua, displayed limited comprehension under test conditions, and those words they did understand were closely tied to a specific context. The Kelloggs spent many hours teaching Viki the names of various body parts, but with no success, and the Hayeses drilled Gua with the names of familiar objects, again without success.

More recently, Roger Fouts has suggested that Washoe, Ali, and a few other apes understand at least three or four words. Unfortunately the data are few and the number of overall correct responses, even to a word that is thought to be understood, are extremely low. Even though the data suggest that there is a statistically
significant difference between words that are recognizable and those that are not, these words are understood on such a small percentage of occasions that most oral communications made in real time would be missed. Francine Patterson also suggests comprehension of speech for Koko the gorilla, but she lacks the test data to rule out the impact of contextual information. It may be that other apes show some speech comprehension, but none of them seem to have made the leap into language comprehension that Kanzi was on the verge of at this time.