Chimpanzees

 

 

 

Chimpanzees and bonobos (otherwise known as dwarf or pygmy chimpanzees) belong to the Pongidae family, and are found only in Africa. These primates use their hands and feet for climbing trees and gathering the fruits and leaves which form the major part of their diet. Only occasionally havethey been known to eat small mammals and invertebrates. Chimpanzees are themselves sometimes captured and eaten by large carnivores such as leopards and lions. However, the principal threats to primates are caused by humans who increasingly destroy their forest habitat.

 

Chimpanzees (Pan troglodytes) are found in various regions of Tropical Africa. They live in a variety of habitats, ranging from humid forests to dry savannah woodlands. They are highly social, living in communities of between 20 and 100 individuals with stable sub­groups. Chimpanzees become sexually mature when they are between 10 and 13 years old. Females usually produce babies every six years, and often do not have more than about three offspring during their lifetime. The IUCN-The World Conservation Union's Species Survival Commission lists two of the three chimpanzee subspecies as Vulnerable and one as Endangered. The western subspecies (P.t.verus) One of the largest populations of this subspecies is most probably to be found in the Côte d'Ivoire (a recent estimate gives 12,000 as a possible figure) and other populations can be found in Guinea, Sierra Leone, and Liberia. Cleared woodland for agriculture has already severely reduced their habitat. Some countries in western Africa have passed laws to protect these chimpanzees, which IUCN lists as Endangered. However, these laws are not always enforced effectively, and the chimpanzees continue to disappear at an alarming rate. There is, therefore, a clear need for more protected areas with adequate staffing and greater financial support. The central subspecies (P.t.troglodytes) This chimpanzee is found throughout seven central African countries. The most serious threats posed in these areas are habitat loss and hunting for meat. Few animals are still captured for the export trade and some countries have introduced legal measures to protect their populations of chimpanzees. The eastern subspecies (P.t. schweinfurthi) Most eastern chimpanzees are thought to live in eastern Zaïre. However, the subspecies is also to be found in the western forests of Uganda and Tanzania, with a few small scattered groups in Rwanda, Burundi, and Sudan. The rapidly expanding human populations clear forests to grow food crops and thus destroy and fragment the chimpanzees' habitat. The Bonobo (Pan paniscus) Bonobos are to be found only in the Central Zaïre Basin. These forest­dwelling apes live in communities that may contain between 30 and 80 individuals. These communities divide up into foraging groups of six or more animals who hunt for food together. The diet of bonobos, consisting mostly of fruit, is similar to that of the common chimpanzee. IUCN regards the bonobo as Vulnerable. As with the chimpanzees, habitat alteration, through logging in the tropical rainforests of central Africa or habitat destruction for agriculture in the densely populated countries of west and east­central Africa, pose the most serious threat to the bonobos. Conservation measures Much more research, especially into population figures and distribution is essential so that conservationists can determine in which areas chimpanzees are most vulnerable, and decide what action needs to be taken. Long­term chimpanzee research projects are in progress in a number of areas: Tai, Côte d'Ivoire; Kibale, Uganda; Boussou, Guinea; Lopé, Gabon - the longest­running sites being Gombe and Mahale in Tanzania. Historically, capture for medical research had decimated some populations of chimpanzees. Targeting adult females in order to capture their infants has devastated some groups, but fortunately, this is now relatively rare. The World Health Organization (WHO) has stressed the need to minimize the trade in primates for biomedical research. The WHO recommends that Endangered, Vulnerable, or Rare species should be used in biomedical research only if they are obtained from self­sustaining captive breeding colonies. The USA has banned the importation of chimpanzees for biomedical research purposes and it is to be hoped that other countries will soon follow. Both WWF and IUCN are working to ensure the long­term survival of the chimpanzee and the bonobo. Support is given to the following measures: environmental education protection by law restriction or regulation of national and international trade reintroduction projects for chimpanzees establishing new protected areas *IUCN Classifications of Degrees of Threat By classifying species into categories of threat, conservation recommendations can be made based on the status of the species, its abundance, and distribution. Both IUCN and WWF are preparing action priorities to guide wolf and jackal conservation. Extinct: Species has not been located in the wild during the past 50 years. Endangered: Species in danger of Extinction. Survival is unlikely if the cause of its decline continues. Vulnerable: Species believed likely to become endangered in the near future if the cause of its decline continues. Rare: Species with small world populations that are not at present Endangered or Vulnerable. Threatened: A general term used to describe a species in one of the above categories. Recommended further reading: Threatened Primates of Africa, IUCN Red Data Book, 1988. Oates, J.F., IUCN/SSC Primate Specialist Group, Action Plan for African Primate Conservation: 1986­90, 1985

Scientists determine chimpanzees have 'culture' By JOSEPH B. VERRENGIA -- The Associated Press Female chimpanzee Yoshi holds her new baby, Toshi, Wednesday, March 3, 1999, at the Los Angeles Zoo. (AP Photo: Nick Ut) Some chimpanzees greedily slurp ants off a stick as if it were a wriggling lollipop, while others daintily pluck them, one by one. Some chimps mop their brows with leaves; others demurely raise their arms while companions groom them. Researchers now agree that the variety of behavior exhibited by mankind's closest relative can be summed up in a single word: culture. It is the first time scientists have concluded that a species other than humans has a culture, or a way of life based on customs that are learned and shared rather than genetically programmed. "The evidence is overwhelming that chimpanzees have a remarkable ability to invent new customs and technologies, and they pass these on socially," said primatologist Frans de Waal of Emory University. The study, conducted by primatologist Andrew Whiten of the University of St. Andrews in Scotland and others, was published Thursday in the journal Nature. The findings are based on an analysis of chimp data spanning five decades. Jane Goodall, the world-renowned scientists who has been observing primates at Gombe Stream in Tanzania since 1960 in the longest-running animal behavior project, co-wrote the study. The research found at least 39 customs related to chimps' tool use, grooming and courtship. The customs vary widely from group to group, much as they do in humans. The scientists said it is too early to tell if some chimp cultures are more advanced than others. "What we see in wild chimps, on a lesser scale, is the sort of cultural diversity that we would see in traditional human societies," said primatologist Craig Stanford of the University of Southern California. Chimps and ancestral humans split on the evolutionary tree more than 4 million years ago, but the ape's genetic code still overlaps ours by more than 98 percent. Primatologists generally consider chimps to be as mentally capable as a 4-year-old child, and they share many practices with primitive human cultures, including social bonds, certain hunting habits and the use of plants for medicinal purposes. Many animal species learn fundamental survival skills from their parents, and their habits differ depending on where they live. Songbirds, for example, learn local dialects of their species' song. Dolphins swim in groups and have a complex communications system, while elephants display a range of emotions, including grief. But the extensive types of behavior among chimps are unparalleled and are not necessarily dictated by particular boundaries or environments. In Tanzania, chimps at Gombe routinely use sticks to probe the ground for termites, but chimps 100 miles away in the Mahale Mountains do not. Gombe chimps don't use stones to crack nuts, even though their terrain is strewn with rocks. But Tai rainforest chimps in the Ivory Coast use stone tools even though rocks are scarce. At Tai, grooming chimps wipe parasites on their forearms before mashing them with their forefingers. At Gombe, groomers mash parasites on a leaf. What remains unresolved is the origins' of chimp customs and precisely how they are shared. "We're just now beginning to videotape families to see how they acquire these behaviors," said Ann Pusey of the University of Minnesota. The findings raise an important new consideration in the conservation of chimpanzees' rapidly dwindling populations across Africa. Logging, hunting and farming have reduced the chimp population to less than 200,000, down from the millions of chimpanzees 100 years ago. "We are not just losing chimpanzees," Whiten said. "We are losing the diversity of chimpanzee cultures."

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