Summary

Abstract

The orang-utan is a superb representative of a major sector of the structure of biological diversity in Sumatra and Borneo. Conservation of the living conditions of the orang-utan implies maintaining the integrity of the entire natural ecosystem of indigenous plant and animal species known as the West Malesian rainforest, i.e. the natural tropical evergreen forests of distinctive floral composition which stretch from the isthmus of Kra, in Thailand, across peninsular West Malaysia, south and eastwards, including Sumatra, Borneo and Java.