Behavioral and Brain Sciences

Short Communication

“Magical number 5” in a chimpanzee

Nobuyuki Kawai a1 and Tetsuro Matsuzawa a1
a1 Section of Language and Intelligence, Department of Behavior Brain Science, Primate Research Institute, Kyoto University, Kanrin, Inuyama City, Aichi Pref. Japan 484-8506


One of our recent studies has revealed that a numerically trained chimpanzee can memorize a correct sequence of five numbers shown on a monitor. Comparative investigations with humans show very similar patterns of errors in the two species, suggesting humans and chimpanzee share homologous memory processes. Whether or not 5 is a pure capacity limit for the chimpanzee remains an empirical question.