Koehler and Tool Use in Orang-Utans

Abstract

We will comment on some specific behaviors observed by Koehler, on the basis of our studies of semi-wild orang-utans conducted in 1991 and 1992 at Sepilok/Sandakan and Semengoh/Kuching Orang-utan Rehabilitation Centers in East Malaysia. Most of our comments refer to tool use, although these may be connected with other observations.