Ecology and Natural History

Abstract

Since the earliest reports, it has been known that orang-utans are fruit eaters. Frugivory has important implications for many aspects of an animal's biology and in particular its way of life. Thus, the quantitative and qualitative distribution of the ape's fruit diet in time and space will be a major determinant of its ranging behaviour, population density and, consequently, social organisation. Field researchers during the 1970s habituated for the first time small populations of resident apes in particular, well-studied areas, and since then biologists have acquired some insight into the complex lifestyle of the orang-utan.