The chimpanzee (Pan troglodytes), also known as the common chimpanzee, robust chimpanzee, or simply "chimp," is a species of great ape, with four confirmed subspecies and a fifth proposed subspecies. The chimpanzee, along with the closely related bonobo (sometimes called the pygmy chimpanzee), is a species in the genus Pan. Evidence from fossils and DNA sequencing shows both species of the genus Pan constitute a sister taxon to the modern human lineage.
Temporal range: 4–0 Ma
|distribution of subspecies|
1. Pan troglodytes verus (green)
2. P. t. ellioti (gray)
3. P. t. troglodytes (red)
4. P. t. schweinfurthii (blue)
The chimpanzee is covered in coarse black hair, but has a bare face, fingers, toes, palms of the hands, and soles of the feet. It is considered more robust than the bonobo, weighing between 40 and 65 kg (88 and 143 lb) and measuring about 63 to 94 cm (25 to 37 in). Its gestation period is eight months. The infant is weaned at about three years old, but usually maintains a close relationship with its mother for several more years; it reaches puberty at the age of 8 to 10. Its lifespan in the wild can exceed 40 years and its lifespan in captivity is about 50 years.
The chimpanzee lives in groups which range in size from 15 to 150 members, although individuals travel and forage in much smaller groups during the day. The species lives in a male-dominated, strict hierarchy, which means disputes can generally be settled without the need for violence. Nearly all chimpanzee populations have been recorded using tools, modifying sticks, rocks, grass and leaves and using them for acquiring honey, termites, ants, nuts and water. The species has also been found creating sharpened sticks to spear Senegal bushbabies out of small holes in trees.
The chimpanzee is listed on the IUCN Red List as an endangered species. Between 170,000 and 300,000 individuals are estimated across its range in the forests and savannahs of West and Central Africa. The biggest threats to the chimpanzee are habitat loss, poaching and disease.
The common chimpanzee was named Simia troglodytes by Johann Friedrich Blumenbach in 1776; Lorenz Oken moved it to the new genus Pan in 1816. The species name troglodytes is a reference to the Troglodytae (literally "cave-goers"), an African people described by Greco-Roman geographers. Blumenbach first used it in his De generis humani varietate nativa liber ("[Book] on the natural varieties of the human genus") in 1776. This book was based on his dissertation presented one year before (it had a date 16 September 1775 printed on its title page) to the University of Göttingen for internal use only, thus the dissertation did not meet the conditions for published work in the sense of zoological nomenclature.
The English name "chimpanzee" is first recorded in 1738. It is derived from Vili ci-mpenze or Tshiluba language chimpenze, with a meaning of "mockman" or possibly just "ape". The colloquialism "chimp" was most likely coined some time in the late 1870s.
Despite a large number of Homo fossil finds, chimpanzee fossils (genus Pan) were not described until 2005. Existing chimpanzee populations in West and Central Africa do not overlap with the major human fossil sites in East Africa. However, chimpanzee fossils have now been reported from Kenya. This would indicate that both humans and members of the Pan clade were present in the East African Rift Valley during the Middle Pleistocene.
DNA evidence suggests the bonobo and common chimpanzee species separated from each other less than one million years ago (similar in relation between Homo sapiens and Neanderthals). A 2017 genetic study suggests ancient gene flow (introgression) between 200 and 550 thousand years ago from the bonobo into the ancestors of central and eastern chimpanzees. The chimpanzee line split from the last common ancestor of the human line around six million years ago. Because no species other than Homo sapiens has survived from the human line of that branching, both chimpanzee species are the closest living relatives of humans; the lineage of humans and chimpanzees diverged from genus Gorilla about seven million years ago. A 2003 study argues the common chimpanzee should be included in the human branch as Homo troglodytes, and notes "experts say many scientists are likely to resist the reclassification, especially in the emotionally-charged and often disputed field of anthropology".
- Central chimpanzee or tschego, Pan troglodytes troglodytes, in Cameroon, the Central African Republic, Equatorial Guinea, Gabon, the Republic of the Congo, and the Democratic Republic of the Congo
- Western chimpanzee, P. troglodytes verus, in Guinea, Guinea-Bissau, Mali, Senegal, Sierra Leone, Liberia, Ivory Coast, and Ghana
- Nigeria-Cameroon chimpanzee, P. troglodytes ellioti (also known as P. t. vellerosus), in Nigeria and Cameroon
- Eastern chimpanzee, P. troglodytes schweinfurthii, in the Central African Republic, South Sudan, the Democratic Republic of the Congo, Uganda, Rwanda, Burundi, Tanzania, and Zambia
- Southeastern chimpanzee, P. troglodytes marungensis, in Burundi, Rwanda, Tanzania, and Uganda: Colin Groves argues that this subspecies is the result of enough variation between the northern and southern populations of P. t. schweinfurthii.
|NCBI genome ID|
|Genome size||3,323.27 Mb|
|Number of chromosomes||24 pairs|
Human and common chimpanzee DNA are very similar. After the completion of the Human Genome Project, a Chimpanzee Genome Project was initiated. In December 2003, a preliminary analysis of 7600 genes shared between the two genomes confirmed that certain genes, such as the forkhead-box P2 transcription factor which is involved in speech development, have undergone rapid evolution in the human lineage. A draft version of the chimpanzee genome was published on 1 September 2005, in an article produced by the Chimpanzee Sequencing and Analysis Consortium.
The DNA sequence differences between humans and chimpanzees is about 35 million single-nucleotide changes, five million insertion/deletion events, and various chromosomal rearrangements. Typical human and chimp protein homologs differ in only an average of two amino acids. About 30% of all human proteins are identical in sequence to the corresponding chimp protein. Duplications of small parts of chromosomes have been the major source of differences between human and chimp genetic material; about 2.7% of the corresponding modern genomes represent differences, produced by gene duplications or deletions, during the roughly four to six million years since humans and chimps diverged from their common evolutionary ancestor. Results from human and chimp genome analyses, currently being conducted by geneticists including David Reich, should help in understanding the genetic basis of some human diseases. Research into genetic conditions in wild chimpanzees has also been undertook.
The adult male common chimpanzee weighs between 40 and 60 kg (88 and 132 lb), the female weighs 32 to 47 kg (71 to 104 lb). However, large wild males can weigh up to 70 kg (150 lb) and males in captivity, such as Travis the Chimp, have reached 91 kg (201 lb). Head-body length (from the nose to the rump while on all fours) ranges from 63 to 94 cm (25 to 37 in). Males can measure up to 1.6 m (5 ft 3 in) tall while standing and females up to 1.3 m (4 ft 3 in) tall. Their bodies are covered by coarse, black hair, except for the face, fingers, toes, palms of the hands, and soles of the feet. Both its thumbs and big toes are opposable, allowing a precise grip. The common chimpanzee is both arboreal and terrestrial, and spends its nights in the trees, while most daylight hours are spent on the ground.
Its habitual gait is quadrupedal, using the soles of its feet and resting on its knuckles, but it can walk upright for short distances. The common chimpanzee is a 'knuckle walker', like the gorilla and the bonobo, in contrast to the quadrupedal locomotion of the orangutan, a 'palm walker' that uses the outside edge of its palms. It is the anatomically closest relative of the human.
The common chimpanzee is a highly adaptable species. It lives in a variety of habitats, including dry savanna, evergreen rainforest, montane forest, swamp forest and dry woodland-savanna mosaic. In Gombe, the chimpanzee lives in subalpine moorland, open woodland, semideciduous forest, evergreen forest, and grassland with scattered trees. At Bossou, the chimpanzee inhabits multistage secondary deciduous forests, which have grown after shifting cultivation, as well as primary forests and grasslands. At Taï, it can be found in the last remaining tropical rain forest in Ivory Coast. The chimpanzee has an advanced cognitive map of its home range and can repeatedly find food. The chimpanzee makes a night nest in a tree in a new location every night, with every chimpanzee in a separate nest other than infants or juvenile chimpanzees, which sleep with their mothers.
The chimpanzee is an omnivorous frugivore. It prefers fruit above all other food items and even seeks out and eats them when they are not abundant. It also eats leaves and leaf buds, seeds, blossoms, stems, pith, bark and resin. Insects and meat make up a small proportion of their diet, estimated as 2%. While the common chimpanzee is mostly herbivorous, it does eat honey, soil, insects, birds and their eggs, and small to medium-sized mammals, including other primates. The western red colobus ranks at the top of preferred mammal prey. Other mammalian prey include red-tailed monkeys, yellow baboons, bush babies, blue duikers, bushbucks, and common warthogs. Isolated cases of cannibalism have also been documented.
Despite the fact that common chimpanzees are known to hunt, and to collect insects and other invertebrates, such food actually makes up a tiny portion of their diet, from as little as 2% yearly to as much as 65 grams of animal flesh per day for each adult chimpanzee in peak hunting seasons. This also varies from troop to troop and year to year. However, in all cases, the majority of their diet consists of fruits, leaves, roots, and other plant matter. Female chimpanzees appear to consume much less animal flesh than males, according to several studies. Goodall documented many occasions within Gombe Stream National Park of chimpanzees and western red colobus monkeys ignoring each other within close proximity.
Predators and parasitesEdit
Leopard predation is apparently a significant cause of mortality in chimpanzees at Taï and Lopé National Parks. Chimps are generally hostile towards leopards and may mob the predators and even kill their cubs. Lions may have preyed on the chimpanzees at Mahale Mountains National Park, where at least four chimpanzees could have fallen prey to lions. Although no other instances of lion predation on chimpanzees have been recorded, the larger group sizes of savanna chimps may have developed as a response to threats from these big cats.
Despite being 98% related, chimps and humans share only 50% of parasite and microbe species. This is due to the differences in environmental and dietary adaptations with human internal parasite species overlapping more with omnivorous, savanna dwelling baboons. The chimpanzee is host to the louse species Pediculus schaeffi which is a close relative of Pediculus humanus which infests human head and body hair. By contrast, the human pubic louse Pthirus pubis is closely related to Pthirus gorillae which infests gorillas. A 2017 study of gastrointestinal parasites of wild chimps in degraded forests in Uganda found nine species of protozoa, five nematodes, one cestode, and one trematode. The most prevalent species being the protozoa Troglodytella abrassarti.
It is suspected that human observers can influence chimpanzee behaviour. It is suggested that drones, camera traps and remote microphones should be used rather than human observers.
Common chimpanzees live in communities that typically range from 20 to more than 150 members, but spend most of their time traveling in small, temporary groups consisting of a few individuals, which may consist of any combination of age and sex classes. Both males and females sometimes travel alone. The common chimpanzee lives in a fission-fusion society and may be found in groups of these types: all-male, adult females and offspring, both sexes, or one female and her offspring. Chimpanzees have complex social relationships and spend a large amount of time grooming each other.[check quotation syntax] At the core of social structures are males, which roam around, protect group members, and search for food. Males remain in their natal communities, while females generally emigrate at adolescence. As such, males in a community are more likely to be related to one another than females are to each other. Among males is generally a dominance hierarchy, and males are dominant over females. However, this unusual fission-fusion social structure, "in which portions of the parent group may on a regular basis separate from and then rejoin the rest," is highly variable in terms of which particular individual chimpanzees congregate at a given time. This is mainly due to chimpanzees having a high level of individual autonomy within their fission-fusion social groups. Also, communities have large ranges that overlap with those of other groups.
As a result, individual chimpanzees often forage for food alone, or in smaller groups (as opposed to the much larger "parent" group, which encompasses all the chimpanzees which regularly come into contact and congregate into parties in a particular area). As stated, these smaller groups also emerge in a variety of types, for a variety of purposes. For example, an all-male troop may be organized to hunt for meat, while a group consisting of lactating females serves to act as a "nursery group" for the young. An individual may encounter certain individuals quite frequently, but have run-ins with others almost never or only in large-scale gatherings. Due to the varying frequency at which chimpanzees associate, the structure of their societies is highly complicated.
Male chimpanzees exist in a linear dominance hierarchy. Top-ranking males tend to be aggressive even during dominance stability. This is likely due to the chimp’s fission-fusion society, with male chimps leaving groups and returning after extended periods of time. With this, a dominant male is unsure if any "political maneuvering" has occurred and must re-establish his dominance. Thus, a large amount of aggression occurs 5–15 minutes after a reunion. During aggressive encounters, displays are preferred over attacks.
Males maintain and improve their social ranks by forming coalitions, which have been characterized as "exploitative" and are based on an individual’s influence in agonistic interactions. Being in a coalition allows males to dominate a third individual when they could not by themselves, as politically apt chimps can exert power over aggressive interactions regardless of their rank. Coalitions can also give an individual male the confidence to challenge a dominant male. The more allies a male has, the better his chance of becoming dominant. However, most changes in hierarchical rank are caused by dyadic interactions. Chimpanzee alliances can be very fickle and one member may turn on another if it serves him.
Low-ranking males commonly switch sides in disputes between more dominant individuals. Low-ranking males benefit from an unstable hierarchy and have increased sexual opportunities. In addition, conflicts between dominant males cause them to focus on each other rather than the lower-ranking males. Social hierarchies among adult females tend to be weaker. Nevertheless, the status of an adult female may be important for her offspring. Females in Taï have also been recorded to form alliances. Social grooming appears to be important in the formation and maintenance of coalitions. It is more common among adult males than adult females.
Chimpanzees have been described as highly territorial and are known to kill other chimps, although Margaret Power wrote in her 1991 book The Egalitarians that the field studies from which the aggressive data came, Gombe and Mahale, use artificial feeding systems that increased aggression in the chimpanzee populations studied, so might not reflect innate characteristics of the species as a whole. In the years following her artificial feeding conditions at Gombe, Jane Goodall described groups of male chimps patrolling the borders of their territory, brutally attacking chimps which had split off from the Gombe group. A study published in 2010 found that the chimpanzees wage wars over land, not mates. Patrol parties from smaller groups are more likely to avoid contact with their neighbors. Patrol parties from large groups even take over a smaller group's territory, gaining access to more resources, food, and females.
Mating and parentingEdit
Chimpanzees mate throughout the year, although the number of females in oestrus varies seasonally in a group. Female chimps are more likely to come into oestrus when food is readily available. Oestrous females exhibit sexual swellings. Chimps tend to be promiscuous, and during estrus females mate with several males in her community, and males have large testicles for sperm competition. However, other forms of mating also exist. A community's dominant males sometimes restrict reproductive access to females. A male and female can form consortship and mate outside their community. In addition, females sometimes leave their communities and mate with males from neighboring communities.
These alternative mating strategies give females more mating opportunities without losing the support of the males in their community. Infanticide has been recorded in chimp communities in Gombe, Mahale, and Kibale National Parks. Male chimps practice infanticide on unrelated young to shorten the interbirth intervals in the females. Also, accounts of infanticide by females have been reported; cases of female infanticide may be related to the dominance hierarchy in females or simply isolated pathological behaviors.
Care for the young is provided mostly by their mothers. The survival and emotional health of the young is dependent on maternal care. Mothers provide their young with food, warmth, and protection, and teach them certain skills. In addition, a chimp’s future rank may be dependent on its mother’s status. For their first 30 days, infants cling to their mother's bellies. Newborn chimps are helpless; their grasping reflex is not strong enough to support them for more than a few seconds. Infants are unable to support their own weight for their first two months and need their mothers' support.
When they reach five to six months, infants ride on their mothers’ backs. They remain in continual contact for the rest of their first year. When they reach two years of age, they are able to move and sit independently. By three years, infants move farther away from their mothers. By four to six years, chimps are weaned and infancy ends.
The juvenile period for chimps lasts from their sixth to ninth years. Juveniles remain close to their mothers, but they also have more interactions with other members of their community. Adolescent females move between groups and are supported by their mothers in agonistic encounters. Adolescent males spend time with adult males in social activities like hunting and boundary patrolling.
Chimpanzees use a variety of facial expressions, postures and sounds to communicate with each other. Chimps have expressive faces which are important in close-up communications. When frightened, a "full closed grin" causes nearby individuals to be fearful, as well. Other facial expressions include the "lip flip", "pout", "sneer", and "compressed-lips face". When submitting to a conspecific, a chimp crunches, bobs, and extends a hand. When in an aggressive mode, a chimp swaggers bipedally, hunched over and arms waving, in an attempt to exaggerate its size. Chimps beat their hands and feet against the trunks of large trees, an act known as "drumming".
Vocalizations are also important in chimp communication. The most common and important call in adults is the "pant-hoot". These calls are made when individuals are excited. Pant-hoots are made of four parts, starting with soft "hoos" that get louder and louder and climax into screams and sometimes barks; the former die down to soft "hoos" again as the call ends. Submissive individuals will make "pant-grunts" towards their superiors. Chimps use distance calls to draw attention to danger, food sources, or other community members. "Barks" may be made as "short barks" when hunting and "tonal barks" when sighting large snakes.
When hunting small monkeys such as the red colobus, the chimpanzee hunts where the forest canopy is interrupted or irregular. This allows it to easily corner the monkeys when chasing them in the appropriate direction. Chimps may also hunt as a coordinated team, so that they can corner their prey even in a continuous canopy. During an arboreal hunt, each chimp in the hunting groups has a role. "Drivers" serve to keep the prey running in a certain direction and follow them without attempting to make a catch. "Blockers" are stationed at the bottom of the trees and climb up to block prey that take off in a different direction. "Chasers" move quickly and try to make a catch. Finally, "ambushers" hide and rush out when a monkey nears. While both adults and infants are taken, adult male black-and-white colobus monkeys will attack the hunting chimps. In Gombe, the chimpanzee also fears adult female colobus monkeys, and prefers to snatch infants from their mother's bellies without harming the mothers. Male chimps hunt more than females. When caught and killed, the meal is distributed to all hunting party members and even bystanders.
Intelligence and cognitionEdit
Nearly all chimpanzee populations have been recorded using tools. They modify sticks, rocks, grass, and leaves and use them when foraging for honey, termites, ants, nuts, and water. Despite the lack of complexity, forethought and skill are seen in making these tools and should be considered such. While it has been known since Jane Goodall's 1960s discovery that modern chimpanzees use tools, research published in 2007 indicates chimpanzee stone tool use dates to at least 4,300 years ago.
A common chimpanzee from the Kasakela chimpanzee community was the first nonhuman animal reported making a tool, by modifying a twig to use as an instrument for extracting termites from their mound. At Taï, chimps simply use their hands to extract termites. When foraging for honey, chimps use modified short sticks to scoop the honey out of the hive, that is, if the bees are stingless. For hives of the dangerous African honeybees, chimps use longer and thinner sticks to extract the honey. Chimps also fish for ants using the same tactic.
Ant dipping is difficult and some chimps never master it. West African chimps crack open hard nuts with stones or branches. Some forethought in this activity is apparent, as these items are not found together or near a source of nuts. Nut cracking is also difficult and must be learned. Chimps also use leaves as sponges or spoons to drink water.
A recent study revealed the use of such advanced tools as spears, which West African chimpanzees in Senegal sharpen with their teeth, being used to spear Senegal bushbabies out of small holes in trees. An eastern chimpanzee has been observed using a modified branch as a tool to capture a squirrel.
A 30-year study at Kyoto University's Primate Research Institute has shown that chimps are able to learn to recognise the numbers 1 through 9 and their values. The chimps further show an aptitude for photographic memory, demonstrated in experiments in which the jumbled digits are flashed onto a computer screen for less than a quarter of a second. One chimp, Ayumu, was able to correctly and quickly point to the positions where they appeared in ascending order. The same experiment was failed by human world memory champion Ben Pridmore on most attempts.
In controlled cooperative experiments researchers have found that chimpanzees have a basic understanding of cooperation. Chimpanzees recruit the best collaborators. In a group setting with a device that delivered food rewards only to cooperating chimpanzees, cooperation first increased, then, due to competitive behaviour, decreased, before finally increasing to the highest level through punishment and other arbitrage behaviour.
Chimpanzees, gorillas, and orangutans show laughter-like vocalizations in response to physical contact, such as wrestling, play-chasing, or tickling. This is documented in wild and captive chimpanzees. Common chimpanzee laughter is not readily recognisable to humans as such, because it is generated by alternating inhalations and exhalations that sound more like breathing and panting. Instances in which nonhuman primates have expressed joy have been reported. One study analyzed and recorded sounds made by human babies and bonobos when tickled. Although the bonobo's laugh was a higher frequency, the laugh followed a pattern similar to that of human babies and included similar facial expressions. Humans and chimpanzees share similar ticklish areas of the body, such as the armpits and belly. The enjoyment of tickling in chimpanzees does not diminish with age.
Possible linguistic capabilitiesEdit
Scientists have long been fascinated with the studies of language, believing it to be a unique human cognitive ability. To test this hypothesis, scientists have attempted to teach human language to several species of great apes. One early attempt by Allen and Beatrix Gardner in the 1960s involved spending 51 months teaching American Sign Language (ASL) to a chimpanzee named Washoe. The Gardners reported Washoe learned 151 signs, and she had spontaneously taught them to other chimpanzees. Over a longer period of time, Washoe learned over 800 signs.
Debate is ongoing among some scientists (such as David Premack), about non-human great apes' ability to learn language. Since the early reports on Washoe, numerous other studies have been conducted, with varying levels of success, including one involving a chimpanzee named jokingly Nim Chimpsky, trained by Herbert Terrace of Columbia University. Although his initial reports were quite positive, in November 1979, Terrace and his team, including psycholinguist Thomas Bever, re-evaluated the videotapes of Nim with his trainers, analyzing them frame by frame for signs, as well as for exact context (what was happening both before and after Nim's signs). In the reanalysis, Terrace and Bever concluded Nim's utterances could be explained merely as prompting on the part of the experimenters, as well as mistakes in reporting the data. "Much of the apes' behaviour is pure drill," he said. "Language still stands as an important definition of the human species." In this reversal, Terrace now argued Nim's use of ASL was not like human language acquisition. Nim never initiated conversations himself, rarely introduced new words, and simply imitated what the humans did. More importantly, Nim's word strings varied in their ordering, suggesting that he was incapable of syntax. Nim's sentences also did not grow in length, unlike human children whose vocabulary and sentence length show a strong positive correlation.
Chimpanzees are rarely represented in African culture, as the locals regard them as too similar to humans and thus "too close for comfort". The Gio people of Liberia and the Hemba people of the Congo have created blocky and crude masks of the animals. The mask may have a smile which suggests drunken anger, insanity or horror. They wear these masks when teaching young people how not to act; performing rituals where they act wildly and uncivilized. They may also act out these rituals during funerals, representing the "awful reality of death". Stories have been told of chimps kidnapping and raping women.
In Western popular culture, chimpanzees have been commonly stereotyped as childlike companions, sidekicks or clowns. They are especially suited for the latter role on account of their prominent facial features, long limbs and fast movements, which humans often find amusing. Accordingly, entertainment acts featuring chimpanzees dressed up as humans have been traditional staples of circuses and stage shows. Westerners have also been disturbed by the chimps' resemblance to humans as well as their "frank sexuality".
In the age of television, a new genre of chimp act emerged in the United States: series whose cast consisted entirely of chimpanzees dressed as humans and "speaking" lines dubbed by human actors. These shows, examples of which include Lancelot Link, Secret Chimp in the 1970s or The Chimp Channel in the 1990s, relied on the novelty of their ape cast to make their timeworn, low comedy gags funny. Their chimpanzee "actors" were as interchangeable as the apes in a circus act, being amusing as chimpanzees and not as individuals. Animal rights groups have urged a stop to this practice, considering it animal abuse. J. Fred Muggs appeared with Today Show host Dave Garroway in the 1950s, Judy on Daktari in the 1960s and Darwin on The Wild Thornberrys in the 1990s. In contrast to the fictional depictions of other animals, such as dogs (as in Lassie), dolphins (Flipper), horses (The Black Stallion) or even other great apes (King Kong), chimpanzee characters and actions are rarely relevant to the plot.
The rare depictions of chimpanzees as individuals rather than stock characters, and as central rather than incidental to the plot are generally found in works of science fiction. Robert A. Heinlein's short story "Jerry Was a Man" (1947) centers on a genetically enhanced chimpanzee suing for better treatment. The 1972 film Conquest of the Planet of the Apes, the third sequel of Planet of the Apes, portrays a futuristic revolt of enslaved apes led by the only talking chimpanzee, Caesar, against their human masters.
Chimpanzees have traditionally been kept as pets in a few African villages, especially in the Democratic Republic of Congo. In Virunga National Park in the east of the country, the park authorities regularly confiscate chimpanzees from people keeping them as pets.
Chimpanzees are popular as wild pets in many areas despite their strength, aggression, and wild nature. Even in areas where keeping non-human primates as pets is illegal, the exotic pet trade continues to prosper and some people keep chimpanzees as pets, mistakenly believing that they will bond with them for life. As they grow, so do their strength and aggression; some owners and others interacting with the animals have lost fingers and suffered severe facial damage among other injuries sustained in attacks. In addition to the animals' hostile potential and strength well beyond any human being, chimpanzees physically mature a lot more proportionally than do human beings, and even among the most cleanly and well-organized of housekeepers, maintaining cleanliness and control of chimpanzees is physically demanding to the point that it is impossible for humans to control, especially due to the animals' strength and aggression.
Use in researchEdit
As of November 2007, about 1,300 chimpanzees were housed in 10 U.S. laboratories (out of 3,000 great apes living in captivity there), either wild-caught, or acquired from circuses, animal trainers, or zoos.[not in citation given] Most of the labs either conduct or make the chimps available for invasive research, defined as "inoculation with an infectious agent, surgery or biopsy conducted for the sake of research and not for the sake of the chimpanzee, and/or drug testing". Two federally funded laboratories use chimps: the Yerkes National Primate Research Center at Emory University in Atlanta, Georgia, and the Southwest National Primate Center in San Antonio, Texas. Five hundred chimps have been retired from laboratory use in the U.S. and live in animal sanctuaries in the U.S. or Canada.
Chimpanzees used in biomedical research tend to be used repeatedly over decades, rather than used and killed as with most laboratory animals. Some individual chimps currently in U.S. laboratories have been used in experiments for over 40 years. According to Project R&R, a campaign to release chimps held in U.S. labs—run by the New England Anti-Vivisection Society in conjunction with Jane Goodall and other primate researchers—the oldest known chimp in a U.S. lab is Wenka, which was born in a laboratory in Florida on May 21, 1954. She was removed from her mother on the day of birth to be used in a vision experiment that lasted 17 months, then sold as a pet to a family in North Carolina. She was returned to the Yerkes National Primate Research Center in 1957 when she became too big to handle. Since then, she has given birth six times, and has been the subject of research into alcohol use, oral contraceptives, aging, and cognitive studies.
With the publication of the chimpanzee genome, plans to increase the use of chimps in labs are reportedly increasing, with some scientists arguing that the federal moratorium on breeding chimps for research should be lifted. A five-year moratorium was imposed by the U.S. National Institutes of Health in 1996, because too many chimps had been bred for HIV research, and it has been extended annually since 2001.
Other researchers argue that chimps are unique animals and either should not be used in research, or should be treated differently. Pascal Gagneux, an evolutionary biologist and primate expert at the University of California, San Diego, argues, given chimpanzees' sense of self, tool use, and genetic similarity to human beings, studies using chimps should follow the ethical guidelines used for human subjects unable to give consent. Also, a recent study suggests chimpanzees which are retired from labs exhibit a form of posttraumatic stress disorder. Stuart Zola, director of the Yerkes National Primate Research Laboratory, disagrees. He told National Geographic: "I don't think we should make a distinction between our obligation to treat humanely any species, whether it's a rat or a monkey or a chimpanzee. No matter how much we may wish it, chimps are not human."
Some governments have enacted a great ape research ban forbidding the use of chimpanzees and other great apes in research or toxicology testing. As of 2006, Austria, New Zealand, the Netherlands, Sweden, and the UK had introduced such bans.[not in citation given]
Jane Goodall undertook the first long-term field study of the common chimpanzee, begun in Tanzania at Gombe Stream National Park in 1960. Other long-term study sites begun in 1960 include A. Kortlandt in the eastern Democratic Republic of the Congo and Junichiro Itani in Mahale Mountains National Park in Tanzania. Current understanding of the species' typical behaviours and social organization are formed largely from Goodall's ongoing 50-year Gombe research study.
Common chimpanzees have been known to attack humans. In Uganda, several attacks on children have happened, some of them fatal. Some of these attacks may be due to the chimpanzees being intoxicated (from alcohol obtained from rural brewing operations) and mistaking human children for the western red colobus, one of their favorite meals. Human interactions with chimpanzees may be especially dangerous if the chimpanzees perceive humans as potential rivals. At least six cases of chimpanzees snatching and eating human babies are documented.
A chimpanzee's great strength and sharp teeth mean that attacks, even on adult humans, can cause severe injuries. This was evident after the attack and near death of former NASCAR driver St. James Davis, who was mauled by two escaped chimps while he and his wife were celebrating the birthday of their former pet chimp. Another example of chimpanzees being aggressive toward humans occurred in 2009 in Stamford, Connecticut, when a 200-pound (91 kg), 13-year-old pet chimp named Travis attacked his owner's friend, who lost her hands, eyes, nose, and part of her maxilla from the attack.
Link with human immunodeficiency virus type 1Edit
Two types of human immunodeficiency virus (HIV) infect humans: HIV-1 and HIV-2. HIV-1 is the more virulent and easily transmitted, and is the source of the majority of HIV infections throughout the world; HIV-2 is largely confined to west Africa. Both types originated in west and central Africa, jumping from primates to humans. HIV-1 has evolved from a simian immunodeficiency virus (SIVcpz) found in the common chimpanzee subspecies, P. t. troglodytes, native to southern Cameroon. Kinshasa, in the Democratic Republic of Congo, has the greatest genetic diversity of HIV-1 so far discovered, suggesting the virus has been there longer than anywhere else. HIV-2 crossed species from a different strain of HIV, found in the sooty mangabey monkeys in Guinea-Bissau.
Status and conservationEdit
Chimpanzee are a legally protected species in most of their range and can be found both in and outside national parks. Between 172,700 and 299,700 individuals are thought to be living in the wild, a decrease from about a million chimpanzees in the early 1900s.
The biggest threats to the common chimpanzee are habitat destruction, poaching, and disease. Chimpanzee habitats have been limited by deforestation in both West and Central Africa. Road building has caused habitat degradation and fragmentation of chimpanzee populations and may allow poachers more access to areas that had not been seriously affected by humans. While deforestation rates are low in western Central Africa, selective logging may be done outside national parks.
Chimpanzees are a common target for poachers. In Ivory Coast, chimpanzees make up 1–3% of bushmeat sold in urban markets. They are also taken in pet trades despite it being illegal in many countries where they live. Chimpanzees are also hunted for medicinal purposes in some areas. People sometimes kill chimpanzees that threaten their crops. Chimps may also be unintentionally maimed or killed by snares meant for other animals.
Infectious diseases are a main cause of death for chimpanzees. They succumb to many diseases that afflict humans, because the two species are so similar. As human populations grow, so does the risk of disease transmission between humans and chimpanzees.
On 12 June 2015, the U.S. Fish and Wildlife Service announced it will classify all chimpanzees, both wild and captive, as endangered under the Endangered Species Act. Before this ruling, only wild chimpanzees were listed as endangered, while captive chimpanzees were listed as threatened under the act. The final rule was published in the Federal Register of 16 June 2015 (80 FR 34499), and came into effect 90 days after publication on 14 September 2015.
|Wikimedia Commons has media related to:|
- Bili ape
- Prostitution among animals
- Chimp Haven
- Great ape personhood
- Johann Friedrich Blumenbach and the Chimpanzee
- Theory of mind
- The Third Chimpanzee
- Mefou National Park
- Groves, C.P. (2005). Wilson, D.E.; Reeder, D.M., eds. Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Baltimore: Johns Hopkins University Press. p. 183. ISBN 0-801-88221-4. OCLC 62265494.
- Humle T, Maisels F, Oates JF, Plumptre A, Williamson EA (2016). "Pan troglodytes". IUCN Red List of Threatened Species. 2016: e.T15933A17964454. Retrieved 5 September 2016.
- Shah, A.; Rogers, F. (2014). Tales from Gombe. Firefly. pp. 318–320. ISBN 978-1-77085-468-0.
- Colchero F, Rau R, Jones OR, Barthold JA, Conde DA, Lenart A, et al. (November 2016). "The emergence of longevous populations". Proceedings of the National Academy of Sciences of the United States of America. 113 (48): E7681–E7690. doi:10.1073/pnas.1612191113. PMC 5137748. PMID 27872299.
- p. 37 in Blumenbach, J. F. 1776. De generis hvmani varietate nativa liber. Cvm figvris aeri incisis. – pp. , 1–100, , Tab. I-II [= 1–2]. Goettingae. (Vandenhoeck).
- AnimalBase species taxon summary for troglodytes Blumenbach, 1776 described in Simia, version 11 June 2011
- Kroke, circa 2010. Johann Friedrich Blumenbach. Bibliographie seiner Schriften. Göttingen: Universitätsverlag, No. 1 and 2.
- Ride WD, International Commission on Zoological Nomenclature, International Union of Biological Sciences, International Trust for Zoological Nomenclature, eds. (1999). International Code of Zoological Nomenclature (4th ed.). London: International Trust for Zoological Nomenclature. ISBN 978-0853010067.
- "chimpanzee". American Heritage Dictionary (5th ed.). Houghton Mifflin Harcourt Publishing Company. 2011. Retrieved 31 August 2018.
- "chimpanzee". Online Etymology Dictionary. Retrieved 31 August 2018.
- "chimp definition | Dictionary.com". Dictionary.reference.com. Retrieved 2009-06-06.
- Goldman D, Giri PR, O'Brien SJ (May 1987). "A molecular phylogeny of the hominoid primates as indicated by two-dimensional protein electrophoresis". Proceedings of the National Academy of Sciences of the United States of America. 84 (10): 3307–11. Bibcode:1987PNAS...84.3307G. doi:10.1073/pnas.84.10.3307. PMC 304858. PMID 3106965.
- Won YJ, Hey J (February 2005). "Divergence population genetics of chimpanzees". Molecular Biology and Evolution. 22 (2): 297–307. doi:10.1093/molbev/msi017. PMID 15483319.
- Fischer A, Wiebe V, Pääbo S, Przeworski M (May 2004). "Evidence for a complex demographic history of chimpanzees". Molecular Biology and Evolution. 21 (5): 799–808. doi:10.1093/molbev/msh083. PMID 14963091.
- de Manuel M, Kuhlwilm M, Frandsen P, Sousa VC, Desai T, Prado-Martinez J, et al. (October 2016). "Chimpanzee genomic diversity reveals ancient admixture with bonobos". Science. 354 (6311): 477–481. Bibcode:2016Sci...354..477D. doi:10.1126/science.aag2602. PMC 5546212. PMID 27789843.
- Pickrell J (20 May 2003). "Chimps Belong on Human Branch of Family Tree, Study Says". National Geographic News. National Geographic. Retrieved 11 June 2016.
- Groves C (2001). Primate Taxonomy. Washington, DC: Smithsonian Institution Press. pp. 303–307. ISBN 9781560988724.
- Hof J, Sommer V (2010). Apes Like Us: Portraits of a Kinship. Mannheim: Panorama. p. 114. ISBN 978-3-89823-435-1.
- de Manuel M, Kuhlwilm M, Frandsen P, Sousa VC, Desai T, Prado-Martinez J, et al. (October 2016). "Chimpanzee genomic diversity reveals ancient admixture with bonobos". Science. 354 (6311): 477–481. Bibcode:2016Sci...354..477D. doi:10.1126/science.aag2602. PMC 5546212. PMID 27789843.
- Groves, CP (2005). "Geographic variation within eastern chimpanzees (Pan troglodytes cf. schweinfurthii Giglioli, 1872)". Australasian Primatology.[permanent dead link]
- Chimpanzee Sequencing and Analysis Consortium (September 2005). "Initial sequence of the chimpanzee genome and comparison with the human genome". Nature. 437 (7055): 69–87. Bibcode:2005Natur.437...69.. doi:10.1038/nature04072. PMID 16136131.
Cheng Z, Ventura M, She X, Khaitovich P, Graves T, Osoegawa K, et al. (September 2005). "A genome-wide comparison of recent chimpanzee and human segmental duplications". Nature. 437 (7055): 88–93. Bibcode:2005Natur.437...88C. doi:10.1038/nature04000. PMID 16136132.
- Towle I, Irish JD, De Groote I (April 2018). "Amelogenesis imperfecta in the dentition of a wild chimpanzee" (PDF). Journal of Medical Primatology. 47 (2): 117–119. doi:10.1111/jmp.12323. PMID 29112236.
- Cawthon Lang K (13 April 2006). "Primate Factsheets: Chimpanzee (Pan troglodytes)". Retrieved 29 January 2012.
- "Chimpanzee Attack Revives Calls for Federal Primate Law". Fox News. 18 February 2009. Retrieved 28 January 2012.
- Eskeletons. Eskeletons.org Retrieved on 2013-04-18.
- Burnie D, Wilson DE, eds. (2005). Animal: The Definitive Visual Guide to the World's Wildlife. DK Adult. ISBN 978-0789477644.
- WCMC Species sheets
- Janssen E, Janssen P (2006). "Chimpanzee Fact File". African Wildlife Foundation. Retrieved 23 September 2012.
- Poulsen JR, Clark CJ (2004). "Densities, distributions, and seasonal movements of gorillas and chimpanzees in swamp forest in northern Congo". Int J Prim. 25 (2): 285–306. doi:10.1023/B:IJOP.0000019153.50161.58.
- Goodall J (1986). The Chimpanzees of Gombe: Patterns of Behavior. ISBN 978-0-674-11649-8.
- Sugiyama Y, Koman J (1987). "A preliminary list of chimpanzees' alimentation at Bossou, Guinea". Primates. 28 (1): 133–47. doi:10.1007/BF02382192.
- Boesch C, Boesch-Achermann H. (2000) The chimpanzees of the Taï Forest: behavioral ecology and evolution. Oxford, England: Oxford University Press.
- Van Lawick-Goodall, Jane (1968). "The Behaviour of Free-Living Chimpanzees in the Gombe Stream Reserve". Animal Behaviour Monographs (Rutgers University) 1 (3): 167.
- Guernsey P (4 July 2009). "What do chimps eat?". All About Wildlife. Retrieved 22 April 2013.
- Isabirye-Basuta G (1989). "Feeding ecology of chimpanzees in the Kibale Forest, Uganda". In Heltne PG, Marquardt LA. Understanding chimpanzees. Cambridge, (MS): Harvard University Press. pp. 116–27. ISBN 978-0674920910.
- Boesch C, Uehara S, Ihobe H (2002). "Variations in chimpanzee-red colobus interactions". In Boesch C, Hohmann G, Marchant LF. Behavioral diversity in chimpanzees and bonobos. Cambridge, England: Cambridge University Press. pp. 221–30. ISBN 978-0521006132.
- Goodall J (1977). "Infant killing and cannibalism in free-living chimpanzees". Folia Primatologica; International Journal of Primatology. 28 (4): 259–89. doi:10.1159/000155817. PMID 564321.
- "What do Chimps Eat?". 4 July 2009.
- Stanford C. "The Predatory Behavior and Ecology of Wild Chimpanzees". USC. Retrieved 11 September 2013.
- Newton-Fisher NE (1995). "Chimpanzee Hunting Behavior" (PDF). American Scientist. 83 (3): 256. Bibcode:1995AmSci..83..256S.
- "Chimps on the hunt". BBC Wildlife Finder. 24 October 1990. Retrieved 2009-09-22.
- Van Lawick-Goodall J (1968). "The Behaviour of Free-Living Chimpanzees in the Gombe Stream Reserve". Animal Behaviour Monographs. 1 (3): 191.
- Henschel P, Abernethy KA, White LJ (2005). "Leopard food habits in the Lopé National Park, Gabon, Central Africa". Afr J Ecol. 43 (1): 21–8. doi:10.1111/j.1365-2028.2004.00518.x.
- Hiraiwa-Hasegawa M, Byrne RW, Takasaki H, Byrne JM (11 September 2008). "Aggression toward large carnivores by wild chimpanzees of Mahale Mountains National Park, Tanzania". Folia Primatologica; International Journal of Primatology. 47 (1): 8–13. doi:10.1159/000156259. PMID 3557232.
- Tsukahara T (10 September 1992). "Lions eat chimpanzees: The first evidence of predation by lions on wild chimpanzees". American Journal of Primatology. 29 (1): 1–11. doi:10.1002/ajp.1350290102.
- Weiss, Robin A. (2009). "Apes, lice and prehistory". Journal of Biology. 8 (2): 20. doi:10.1186/jbiol114. PMC 2687769. PMID 19232074.
- McLennan, Matthew R.; Hasegawa, Hideo; Bardi, Massimo; Huffman, Michael A. (2017). "Gastrointestinal parasite infections and self-medication in wild chimpanzees surviving in degraded forest fragments within an agricultural landscape mosaic in Uganda". PLoS One. 12 (7). e0180431. doi:10.1371/journal.pone.0180431.
- Watched chimps change their hunting habits
- The Chimpanzees of Tanzania". Wild Kingdom. 31 December 1976.
- Goldberg TL, Wrangham RW (September 1997). "Genetic correlates of social behaviour in wild chimpanzees: evidence from mitochondrial DNA". Animal Behaviour. 54 (3): 559–70. doi:10.1006/anbe.1996.0450. PMID 9299041.
- Pepper JW, Mitani JC, Watts DP (1999). "General gregariousness and specific social preferences among wild chimpanzees". Int J Prim. 20 (5): 613–32. doi:10.1023/A:1020760616641.
- Muller MN (2002). "Agonistic relations among Kanyawara chimpanzees". In Boesch C, Hohmann G, Marchant LF. Behavioural diversity in chimpanzees and bonobos. Cambridge: Cambridge University Press. pp. 112–124. ISBN 0521006139.
- Bygott JD (1979). "Agonistic behavior, dominance, and social structure in wild chimpanzees of the Gombe National Park". In Hamburg DA, McCown ER. The great apes. Menlo Park: Benjamin-Cummings. pp. 73–121. ISBN 978-0805336696.
- de Waal FB (1987). "Dynamic of social relationships". In Smuts BB, Cheney DL, Seyfarth RM, Wrangham RW, Struhsaker TT. Primate societies. Chicago: University of Chicago Press. pp. 421–429. ISBN 978-0226767161.
- Nishida T, Hiraiwa-Hasegawa M (1986). "Chimpanzees and Bonobos: Cooperative Relationships among Males". In Smuts BB, Cheyney DL, Seyfarth RM, Wrangham RW, Struhsaker T. Primate Societies. Chicago and London: The University of Chicago Press. pp. 165–177. ISBN 978-0226767161.
- Pusey A, Williams J, Goodall J (August 1997). "The influence of dominance rank on the reproductive success of female chimpanzees". Science. 277 (5327): 828–31. doi:10.1126/science.277.5327.828. PMID 9242614.
- Stumpf R (2007). "Chimpanzees and bonobos: Diversity within and between species". In Campbell CJ, Fuentes A, Mackinnon KC, Pancer M, Bearder SK. Primates in perspective. New York: Oxford University Press. pp. 321–344. ISBN 978-0195390438.
- Watts DP (2001). "Reciprocity and interchange in the social relationships of wild male chimpanzees" (PDF). Behaviour. 139 (2): 343–370. CiteSeerX 10.1.1.516.3624. doi:10.1163/156853902760102708.
- Walsh B (18 February 2009). "Why the Stamford Chimp Attacked". TIME. Retrieved 2009-06-06.
- Power M (December 1993). "Divergence population genetics of chimpanzees". American Anthropologist. 95 (4): 1010–11. doi:10.1525/aa.1993.95.4.02a00180.
- "Killer Instincts". The Economist. 24 June 2010.
- Wallis J (2002). "Seasonal aspects of reproduction and sexual behavior in two chimpanzee populations: a comparison of Gombe (Tanzania) and Budongo (Uganda)". In Boesch C, Hohmann G, Marchant LF. Behavioural diversity in chimpanzees and bonobos. Cambridge (England): Cambridge University Press. pp. 181–91. ISBN 978-0521006132.
- Gagneux P, Boesch C, Woodruff DS (January 1999). "Female reproductive strategies, paternity and community structure in wild West African chimpanzees". Animal Behaviour. 57 (1): 19–32. doi:10.1006/anbe.1998.0972. PMID 10053068.
- Bard KA (1995). "Parenting in primates". In Bornstein MH. Handbook of parenting. Volume 2: Biology and ecology of parenting. Mahwah, NJ: L Erlbaum Associates. pp. 27–58. ISBN 978-0805837797.
- Fedurek, Pawel; Zuberbühler, Klaus; Semple, Stuart (2017-11-06). "Trade-offs in the production of animal vocal sequences: insights from the structure of wild chimpanzee pant hoots". Frontiers in Zoology. 14: 50. doi:10.1186/s12983-017-0235-8. PMC 5674848. PMID 29142585.
- Crockford C, Boesch C (2005). "Call combinations in wild chimpanzees". Behaviour. 142 (4): 397–421. doi:10.1163/1568539054012047.
- Boesch C (March 2002). "Cooperative hunting roles among taï chimpanzees". Human Nature. 13 (1): 27–46. CiteSeerX 10.1.1.556.2265. doi:10.1007/s12110-002-1013-6. PMID 26192594.
- Boesch C, Boesch H (1993). "Diversity of tool use and tool-making in wild chimpanzees". In Berthelet A, Chavaillon J. The use of tools by human and non-human primates. Oxford, England: Oxford University Press. pp. 158–87. ISBN 978-0198522638.
- Mercader J, Barton H, Gillespie J, Harris J, Kuhn S, Tyler R, Boesch C (February 2007). "4,300-year-old chimpanzee sites and the origins of percussive stone technology". Proceedings of the National Academy of Sciences of the United States of America. 104 (9): 3043–8. Bibcode:2007PNAS..104.3043M. doi:10.1073/pnas.0607909104. PMC 1805589. PMID 17360606.
- Goodall J (1986). The Chimpanzees of Gombe: Patterns of Behavior. The Belknap Press of Harvard University Press. pp. 535–539. ISBN 978-0-674-11649-8.
- Goodall J (1971). In the Shadow of Man. Houghton Mifflin. pp. 35–37. ISBN 978-0-395-33145-3.
- "Gombe Timeline". Jane Goodall Institute. Archived from the original on 25 January 2008. Retrieved 2009-03-05.
- Stanford CB, Gambaneza C, Nkurunungi JB, Goldsmith ML (July 2000). "Chimpanzees in Bwindi-Impenetrable National Park, Uganda, use different tools to obtain different types of honey". Primates; Journal of Primatology. 41 (3): 337–341. doi:10.1007/BF02557602. PMID 30545184.
- Sugiyama Y (1995). "Drinking tools of wild chimpanzees at Bossou". Am J Primatol. 37 (1): 263–9. doi:10.1002/ajp.1350370308.
- Viegas J (14 April 2015). "Female Chimps Seen Making, Wielding Spears". Retrieved 15 April 2015.
- Huffman MA, Kalunde MS (January 1993). "Tool-assisted predation on a squirrel by a female chimpanzee in the Mahale Mountains, Tanzania". Primates. 34 (1): 93–8. doi:10.1007/BF02381285.
- The study was presented in a Channel 5 (UK) documentary "The Memory Chimp", part of the channel's Extraordinary Animals series.
- Melis, Alicia P.; Hare, Brian; Tomasello, Michael (2006b). "Chimpanzees recruit the best collaborators". Science. 311 (5765): 1297–1300. Bibcode:2006Sci...311.1297M. doi:10.1126/science.1123007. PMID 16513985.
- Suchak, Malini; Eppley, Timothy M.; Campbell, Matthew W.; Feldman, Rebecca A.; Quarles, Luke F.; de Waal, Frans B. M. (2016). "How chimpanzees cooperate in a competitive world". Proceedings of the National Academy of Sciences. 113 (36): 10215–10220. doi:10.1073/pnas.1611826113. PMC 5018789. PMID 27551075.
- Johnson, Steven (April 1, 2003). "Emotions and the Brain". Discover Magazine. Retrieved 2007-12-10.
- Gardner, R. A.; Gardner, B. T. (1969). "Teaching Sign Language to a Chimpanzee". Science. 165 (3894): 664–672. Bibcode:1969Sci...165..664G. CiteSeerX 10.1.1.384.4164. doi:10.1126/science.165.3894.664. PMID 5793972.
- Allen, G. R.; Gardner, B. T. (1980). "Comparative psychology and language acquisition". In Thomas A. Sebok and Jean-Umiker-Sebok. Speaking of Apes: A Critical Anthology of Two-Way Communication with Man. New York: Plenum Press. pp. 287–329. ISBN 978-0306402791.
- "Language of Bonobos". Great Ape Trust. Archived from the original on August 15, 2004. Retrieved 2012-01-16.
- Wynne, Clive (October 31, 2007). "eSkeptic". Skeptic. Retrieved 2011-01-28.
- Werness HB (2007). The Continuum Encyclopedia of Animal Symbolism in World Art. Continuum International Publishing Group. p. 86. ISBN 978-0826419132.
- Van Riper AB (2002). Science in popular culture: a reference guide. Westport: Greenwood Press. pp. 18–19. ISBN 978-0-313-31822-1.
- "Animal Actors | PETA.org". Nomoremonkeybusiness.com. Retrieved 2011-01-28.
- "Gorilla diary: August – December 2008". BBC News. 20 January 2009. Retrieved 2010-04-28.
- "Chimpanzees Don't Make Good Pets". The Jane Goodall Institute. Archived from the original on 2 February 2015. Retrieved 1 February 2015.
- "End chimpanzee research: overview". Project R&R, New England Anti-Vivisection Society. December 11, 2005. Retrieved 2008-03-24.
- "Chimpanzee lab and sanctuary map". The Humane Society of the United States. Archived from the original on March 7, 2008. Retrieved 2008-03-24.
- "Chimpanzee Research: Overview of Research Uses and Costs". Humane Society of the United States. Archived from the original on March 7, 2008. Retrieved 2008-03-24.
- Lovgren, Stefan. Should Labs Treat Chimps More Like Humans?, National Geographic News, September 6, 2005.
- Chimps Deserve Better, Humane Society of the United States.
- A former Yerkes lab worker. "Release & Restitution for Chimpanzees in U.S. Laboratories " Wenka". Releasechimps.org. Retrieved 2009-06-06.
- Wenka, Project R&R, New England Anti-Vivisection Society.
- Langley, Gill (June 2006). Next of Kin: A Report on the Use of Primates in Experiments, British Union for the Abolition of Vivisection, p. 15, citing VandeBerg JL, Zola SM (September 2005). "A unique biomedical resource at risk". Nature. 437 (7055): 30–2. Bibcode:2005Natur.437...30V. doi:10.1038/437030a. PMID 16136112.
- Bradshaw GA, Capaldo T, Lindner L, Grow G (2008). "Building an inner sanctuary: complex PTSD in chimpanzees" (PDF). J Trauma Dissociation. 9 (1): 9–34. doi:10.1080/15299730802073619. PMID 19042307.
- Guldberg, Helen. The great ape debate,[dead link] Spiked online, March 29, 2001. Retrieved August 12, 2007.
- Langley, Gill (June 2006). Next of Kin: A Report on the Use of Primates in Experiments, British Union for the Abolition of Vivisection, p. 12.
- Cohen JE (Winter 1993). "Going Bananas". American Scholar. pp. 154–157.
- Osborn C (27 April 2006). "Texas man saves friend during fatal chimp attack". The Pulse Journal. Retrieved 2006-06-27.
- "Chimp attack kills cabbie and injures tourists". London: The Guardian. 25 April 2006. Retrieved 2006-06-27.
- "'Drunk and Disorderly' Chimps Attacking Ugandan Children". 9 February 2004. Retrieved 2006-06-27.
- Waterman T (1999). "Ebola Cote D'Ivoire Outbreaks". Stanford University. Retrieved 2008-03-24.
- "Chimp attack doesn't surprise experts". MSNBC. 5 March 2005. Retrieved 2006-06-27.
- "Online Extra: Frodo @ National Geographic Magazine". Ngm.nationalgeographic.com. 15 May 2002. Retrieved 2009-06-06.
- "Birthday party turns bloody when chimps attack". USATODAY. 4 March 2005. Retrieved 2006-06-27.
- Argetsinger A (24 May 2005). "The Animal Within". The Washington Post. Retrieved 2006-06-27.
- Sandoval E (18 February 2009). "911 tape captures chimpanzee owner's horror as 200-pound ape mauls friend". New York: Nydailynews.com. Archived from the original on 19 February 2009. Retrieved 2009-06-06.
- Gallman S (18 February 2009). "Chimp attack 911 call: 'He's ripping her apart'". CNN. Retrieved 2009-06-06.
- Reeves JD, Doms RW (June 2002). "Human immunodeficiency virus type 2". The Journal of General Virology. 83 (Pt 6): 1253–65. doi:10.1099/0022-1317-83-6-1253. PMID 12029140. Archived from the original on 28 December 2012. Retrieved 22 June 2008.
- Keele BF, Van Heuverswyn F, Li Y, Bailes E, Takehisa J, Santiago ML, Bibollet-Ruche F, Chen Y, Wain LV, Liegeois F, Loul S, Ngole EM, Bienvenue Y, Delaporte E, Brookfield JF, Sharp PM, Shaw GM, Peeters M, Hahn BH (July 2006). "Chimpanzee reservoirs of pandemic and nonpandemic HIV-1". Science. 313 (5786): 523–6. Bibcode:2006Sci...313..523K. doi:10.1126/science.1126531. PMC 2442710. PMID 16728595.
- Gao F, Bailes E, Robertson DL, Chen Y, Rodenburg CM, Michael SF, Cummins LB, Arthur LO, Peeters M, Shaw GM, Sharp PM, Hahn BH (February 1999). "Origin of HIV-1 in the chimpanzee Pan troglodytes troglodytes". Nature. 397 (6718): 436–41. Bibcode:1999Natur.397..436G. doi:10.1038/17130. PMID 9989410.
- StFleur N (12 June 2015). "U.S. Will Call All Chimps 'Endangered'". The New York Times Company. The New York Times. Retrieved 13 June 2015.
- U.S. Fish and Wildlife Service. "U.S. Fish and Wildlife Service Finalizes Rule Listing All Chimpanzees as Endangered Under the Endangered Species Act". fws.gov. U.S. Fish and Wildlife Service. Retrieved 13 June 2015.
- General references
|Wikimedia Commons has media related to Common chimpanzee.|
|Wikispecies has information related to Common Chimpanzee|
- Chimpanzee Genome resources
- Primate Info Net Pan troglodytes Factsheets
- U.S. Fish & Wildlife Service Species Profile
- New Scientist 19 May 2003 – Chimps are human, gene study implies
- Video clips and news from the BBC (BBC Wildlife Finder)
- View the common chimpanzee genome in Ensembl
- Human Timeline (Interactive) – Smithsonian, National Museum of Natural History (August 2016).