Kanzi: The Ape at the Brink of the Human Mind by Sue Savage-Rumbaugh

encounters—just as do chimpanzee males. Unlike every other Chomskian I had met, Iain readily allowed that there was a great deal he did not know about apes, though he held fast to his notion that only man could symbolize.
    Although our original intellectual positions seemed very far apart—with Iain proposing a late, sudden origin of language while I favored an early, more gradual efflorescence—we began that day one of the most productive, free-flowing exchanges of ideas I’ve been privileged to enjoy with a colleague. We both listened, and as a result began to modify our ideas. Iain wasn’t afraid to argue forcefully for his views, and neither was I, but somehow this did not keep us from talking to one another, as is so often the case with scientists who disagree. Why not? I think because we each accepted the other’s directness, even bluntness, without offense. We did so out of a mutual recognition of the integrity of the other person’s efforts. It was a remarkable week, one that may become a milestone in our important intellectual journey toward understanding the human mind—with the human/nonhuman boundary suffering badly.
    Fortunately, it was not up to me alone to convince the gathering’s skeptics of the range and inventiveness that characterize ape intelligence. I was aware, of course, of chimpanzees’penchant for using tools, but it wasn’t until Bill McGrew itemized the different types of tools they use, and in the many different circumstances, that its import became fully clear to me, and to others, too. “Chimpanzees are the only nonhuman species in nature to use different tools to solve different problems,” said McGrew, a primatologist at the University of Stirling, Scotland. “They go beyond using the same tool to solve different problems (for example, a sponge of leaves to swab out a fruit-husk or a cranial cavity) or different tools to solve the same problem (for example, probes of bark
or
grass
or
vine to fish for termites). Thus, they have a
tool-kit” 16
    It was Christophe Boesch, of the University of Basel, Switzerland, who grabbed the most attention with his reports of chimpanzees in the tropical rain forest of the Taï National Park, in the Ivory Coast, West Africa. The chimps of the region exploit a rich food resource, that of Coula and Panda nuts, which have to be cracked open to give access to the kernels. The animals gather the nuts and then place them one by one in a depression in an exposed tree root or branch on the forest floor (the anvil). They then pound the nuts one by one with a stone or short branch (the hammer). A skilled practitioner can garner as many as 3800 calories a day in the nut season.
    It takes time to become skilled at nut cracking, however—often as much as eleven years. The animals’ persistence in developing the skill is an indication of the value of the nuts. One of the great advantages of nut cracking is that it allows a mother to provision for her offspring. Coula and Panda nuts are common in Western and Central Africa, but it is only the Taï forest chimp population that has learned to exploit the resource. This is a striking example of a cultural difference between populations. Even more dramatic, however, was Boesch’s observation of mothers actively teaching their offspring the skills of nut cracking.
    Boesch told us how, on one occasion, he saw Salomé and her son Satre cracking Panda nuts. Salomé cracked most of them, and when Satre tried with a partially opened nut, he placed the nut improperly on the anvil. Before he could strike it with the stone hammer, “Salomé took the piece of nut in herhand, cleaned the anvil, and replaced the piece carefully in the correct position,” explained Boesch. “Then, with Salomé observing him, he successfully opened it and ate the second kernel.”
    On another occasion Boesch saw Nina, daughter of Ricci, having difficulty opening nuts using an irregular hammer. Nina kept shifting her position, turning the