Great apes of the world
Great apes are so called because of their size, but these magnificent animals are equally ‘great’ in a metaphorical sense.
The orang-utan, Pongo pygmaeus, confined to the islands of Borneo and Sumatra, is Asia’s only surviving great ape. Mainly solitary and arboreal, it is the largest tree-dwelling primate. Large males can weigh 90 kilos (200 pounds) or more. Orang-utans are sparsely covered in long hair, which darkens with age and ranges in colour from bright orange to dark brown.
African great apes – chimpanzees, bonobos and gorillas – are covered with short, coarse, black hair. Although they are accomplished climbers, they are equally at home on the ground. They usually move around on all fours, but will walk short distances on two legs.
Chimpanzees are mainly found in tropical rainforest, though some frequent savannah woodland. They usually live in loose groups of thirty or more individuals and are extremely vocal communicators. Adult chimpanzees stand about 1.2 metres (four feet) tall and weigh around 45 kilos (100 pounds). The bonobo, Pan paniscus, is slightly smaller and more upright than the chimpanzee. Less comfortable on the ground, it is the most arboreal of Africa’s great apes and is confined to the left bank of the Congo River in the swampy forests of the Democratic Republic of Congo.
The gorilla is the largest of the great apes. An adult male can weigh over 180 kilos (400 pounds). When mature, males develop a silver-grey saddle, hence the name ‘silverback’. Adult females weigh about 90 kilos (200 pounds).
The western lowland gorilla Gorilla gorilla has an estimated population of 10,000. Although it is the most widespread gorilla, numbers are decreasing rapidly. Its population is currently threatened not only by deforestation and the bushmeat trade, but also by potentially devastating outbreaks of the Ebola virus. It lives in flexible social groupings and, in that respect, more closely resembles chimpanzees than other gorillas. It also has a broader diet and consumes a larger proportion of fruit. As with all apes, logging and the bushmeat trade have taken a heavy toll and led to severe fragmentation of the population.
The Grauer’s gorilla, Gorilla beringei graueri, found only in eastern DRC, is less well known. Its population is thought not to exceed 7,000. By virtue of its location, it is highly vulnerable and has been severely affected by both war and illegal mining.
Mountain gorillas, Gorilla beringei beringei, are confined to two small, protected patches of afromontane forest. One population living in Bwindi Impenetrable National Park in Uganda and the contiguous Sarambwe Nature Reserve in DRC. Another population living in the Virunga Massif where Rwanda, Uganda and DRC meet. Along with the Cross River subspecies, Gorilla gorilla diehli, the mountain gorilla is one of the two most endangered apes in the world.
More information on the gorilla subspecies and their range states and conservation status can be found on this interactive map.
And see the IUCN Red Data Book for more information on the status of great apes.