Bonobo (Pan paniscus)

Also known as: Pygmy chimpanzee
  
French: Chimpanzé Nain, Chimpanzé Pygmée
Spanish: Chimpancé Pigmeo
KingdomAnimalia
PhylumChordata
ClassMammalia
OrderPrimates
FamilyHominidae
GenusPan (1)
SizeMale head-body length: 73 - 83 cm (2)
Female head-body length: 70 - 76 cm (2)
Male weight: 40 – 45 kg (3)
Female weight: c. 30 kg (3)
Top facts

The bonobo is classified as Endangered (EN) on the IUCN Red List (1), and listed on Appendix I of CITES (4).

Together with the chimpanzee (Pan troglodytes), the bonobo (Pan paniscus) is man's closest living relative (2). Although a similar size to the better-known chimp, the bonobo is often referred to as the pygmy chimpanzee due to the more slender body shape of this species. Like chimpanzees, bonobos have longer forearms than legs, long fingers and mobile shoulder joints. The coat is black although it may turn grey with age and, in contrast to chimpanzees, the face is black, and the hair on the crown projects sideways, as opposed to backwards (2) (3).

The bonobo is found only in the Democratic Republic of Congo in Central Africa; in an area bounded by the Congo River in the north, the Sankuru-Kasai in the south and west, and the Lualaba in the east (2) (3).

The bonobo inhabits humid primary and secondary lowland rainforest at elevations below 1,500 metres (2) (3).

Bonobos are highly intelligent, social animals. They live in stable communities that may have up to 150 members, although these will usually split into smaller groups in order to forage or travel (2). Swellings on the rump advertise a female's receptivity to mating; there is no specific breeding season (5). A single offspring is born after around eight months of gestation and will be cared for by its mother for almost five years (6). Bonobo society has some very marked differences to those of chimpanzees and this has fascinated researchers since their discovery. In both, males remain in their natal group whilst females disperse, but in contrast to the male-dominated chimpanzee society, females in bonobo groups develop strong relationships and males will often defer to them during feeding (2). The cooperative hunting and aggressive raids on neighbouring groups that male chimpanzees partake in have not been seen amongst bonobos and it may be that these differences are related to a more reliable and widely available food source (2). One of the other striking features of bonobo society is sex, which is commonly used for social communication in order to diffuse situations and create bonds (2). Males and females engage in these encounters with their own sex as well as the opposite sex (2).

Bonobos spend virtually all of their time in the trees, foraging for fruit and sleeping in nests constructed in the branches; on the ground they travel by 'knuckle walking' (2). Fruit makes up a large part of the bonobo diet but they will also consume other plant materials and small vertebrates should the opportunity arise. This species appears to depend more on plant stems in its diet than chimpanzees do, perhaps again explaining the lack of aggression in bonobo groups (2).

Bonobos are not as widespread as their chimpanzee cousins and are threatened by loss of habitat as large areas of rainforest are being cleared to make way for agriculture, for timber extraction and for development (1). Although traditionally not targeted by hunters as a result of local taboos (9), this species is today at risk from the bushmeat trade; the demand for which has recently increased, threatening much of Africa's wildlife (2).

Bonobos are protected by law and international trade is prohibited by their listing on Appendix I of the Convention on International Trade in Endangered Species (CITES) (3). Ex-situ conservation measures cannot be relied upon as a safeguard for this species, as presently no self-sustaining captive population exists (2). The precise impact of the bushmeat trade is currently being investigated by the Bushmeat Working Group, part of the Convention on International Trade in Endangered Species (CITES) (7). The United Nations Environmental Program (UNEP) has recently recognised the urgent need to protect our closest relatives and has established a Great Ape Survival Project (GRASP) aimed at identifying the conservation initiatives required to secure the future of the apes and obtaining political support and funding to allow these to be achieved (8). The Bonobo Conservation Initiative is working in the Democratic Republic of Congo to raise awareness of the plight of this species (9). The main problem in terms of bonobo conservation is that they are only found in a single protected area (Salonga National Park), and even there they are intensively hunted both for their meat as well as for the making of charms (3). Concerted conservation efforts will therefore be required to secure the future of this fascinating ape.

For more information on the bonobo:

Authenticated (09/01/2006) by Matt Richardson, independent primatologist and writer.

  1. IUCN Red List (May, 2011)
    http://www.redlist.org
  2. Macdonald, D. (2001) The New Encyclopedia of Mammals. Oxford University Press, Oxford.
  3. Richardson, M. (2006) Pers. comm.
  4. CITES (April, 2003)
    http://www.cites.org
  5. Primate Info Net (April, 2003)
    http://pin.primate.wisc.edu/factsheets/entry/bonobo
  6. Burnie, D. (2001) Animal. Dorling Kindersley, London.
  7. Bonobo Conservation Initiative (April, 2003)
    http://www.bonobo.org
  8. Bushmeat Working Group (CITES) (April, 2003)
    http://bushmeat.net
  9. GRASP (April, 2003)
    http://www.unep.org/grasp/