Chimpanzees can Write with Plastic Symbols

Abstract

The Premacks, Ann James and David, were interested in animal cognition and language very early, at least as early as 1954 (personal communication, David Premack, 1954) and started preparatory work with monkeys soon after that time. In 1964,¹ the Premacks adopted two young female chimpanzees named Sarah and Gussie. Sarah proved to be an excellent student, but Gussie never learned a single word. The Premacks later worked on language training with several other animals, but none of them were as intelligent as Sarah. A characteristic of the Premacks’ work is that their primary interest was in the cognition of chimpanzees, with language regarded more as a window to the chimpanzee mind than as the center of their attention. David Premack’s discussion² of the. relative problem-solving abilities of language-trained and non-language-trained chimpanzees makes that clear. He found striking individual differences in intelligence between chimpanzees in each group, whether language-trained or not: “We have...had both gifted and ungifted animals in each group. Sarah is a bright animal by any standards, but so is Jessie, one of the non-language-trained animals. The groups are also comparable at the other end of the continuum, Peony’s negative gifts being well matched by those of Luvy” (p. 125).