KanzI
in a more recent set of studies, an interesting development relevant to this contro versy came about almost by accident. While Sue Savage-Rumbaugh was attempung to train a bonobo (a pygmy chimpanzee) called Matata how to use the symbols of verkish, Matata's adopted baby, Kanzi, was always with her. Although Matata did not do very well, her son Kanzi spontaneously started using the symbol system with great ease. He had learned not by being taught, but by being exposed to, and observing, a kind of language in use at a very early age. Kanzi eventually developed a large symbol vocabulary (over 250 forms). By the age of eight, he was reported to be able to demonstrate understanding o spoken English at a level comparable to a two-and-a-half-year-old human child. There was also evidence that he was using a consistently distinct set of "gentle noises" as words to refer to things such as bananas, grapes and juice. Kanzi could also use Yerkish to ask for his favorite movie, Quest for Fire, and even learned how to collect wood, make a fire and cook his own food, as shown in the photo at the beginning of this chapter.