The orang-utan is close to extinction in the wild, an event that may occur in our lifetimes. We are familiar with the image of polar bears drowning as ice floes melt. But I think of an orang-utan perched in a small island of trees, stranded by a sea of scorched earth, the remains of once luxuriant tropical rain forest.

Orang-utans are not as well known as chimpanzees and gorillas, but like them, they are our closest-living relatives. But though we share 97 per cent of our genetic make-up, orang-utans are different in many ways. They are calm, gentle, lacking in malice and usually slow-moving. Their greatest pleasure is sitting on a branch, eating fruit. Unlike the social African apes, orang-utans are mostly solitary and have orange-red fur.

The name orang-utan comes from 'orang hutan', Malay for 'person of the forest'. It's a good name, as these apes spend almost all of their time in the forest canopy, feasting on fruit from more than 200 species of tree. Modern scientific studies of the species began in the late 1960s, a decade after similar studies were launched on Africa's great apes.