110-399: The chimpanzee ( / tʃ ɪ m p æ n ˈ z i / ; Pan troglodytes ), also simply known as the chimp , is a species of great ape native to the forests and savannahs of tropical Africa . It has four confirmed subspecies and a fifth proposed one. When its close relative the bonobo was more commonly known as the pygmy chimpanzee, this species was often called the common chimpanzee or
220-525: A clade (from Ancient Greek κλάδος (kládos) 'branch'), also known as a monophyletic group or natural group , is a grouping of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree . In the taxonomical literature, sometimes the Latin form cladus (plural cladi ) is used rather than the English form. Clades are
330-399: A "full closed grin" causes nearby individuals to be fearful, as well. Playful chimpanzees display an open-mouthed grin. Chimpanzees may also express themselves with the "pout", which is made in distress, the "sneer", which is made when threatening or fearful, and "compressed-lips face", which is a type of display. When submitting to a dominant individual, a chimpanzee crunches, bobs, and extends
440-479: A "ladder", with supposedly more "advanced" organisms at the top. Taxonomists have increasingly worked to make the taxonomic system reflect evolution. When it comes to naming , this principle is not always compatible with the traditional rank-based nomenclature (in which only taxa associated with a rank can be named) because not enough ranks exist to name a long series of nested clades. For these and other reasons, phylogenetic nomenclature has been developed; it
550-472: A 2021 study on their abilities to make and use stone flakes, in a similar way as hypothesised for early hominins, did not find this behaviour across two populations of chimpanzees—suggesting that this behaviour is outside the chimpanzee species-typical range. Scientists have attempted to teach human language to several species of great ape. One early attempt by Allen and Beatrix Gardner in the 1960s involved spending 51 months teaching American Sign Language to
660-412: A captive environment. Social grooming appears to be important in the formation and maintenance of coalitions. It is more common among adult males than either between adult females or between males and females. Chimpanzees have been described as highly territorial and will frequently kill other chimpanzees, although Margaret Power wrote in her 1991 book The Egalitarians that the field studies from which
770-465: A chimpanzee jokingly named Nim Chimpsky (in allusion to the theorist of language Noam Chomsky ), 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
880-487: A chimpanzee named Washoe . The Gardners reported that Washoe learned 151 signs, and had spontaneously taught them to other chimpanzees, including her adopted son, Loulis . Over a longer period of time, Washoe was reported to have learned over 350 signs. Debate is ongoing among scientists such as David Premack about chimpanzees' ability to learn language. Since the early reports on Washoe, numerous other studies have been conducted, with varying levels of success. One involved
990-425: A choice between two persons, chimpanzees were just as likely to beg food from a person who could see the begging gesture as from a person who could not, thereby raising the possibility that chimpanzees lack theory of mind . Nearly all chimpanzee populations have been recorded using tools. They modify sticks, rocks, grass, and leaves and use them when foraging for termites and ants, nuts, honey, algae or water. Despite
1100-623: A clade can be described based on two different reference points, crown age and stem age. The crown age of a clade refers to the age of the most recent common ancestor of all of the species in the clade. The stem age of a clade refers to the time that the ancestral lineage of the clade diverged from its sister clade. A clade's stem age is either the same as or older than its crown age. Ages of clades cannot be directly observed. They are inferred, either from stratigraphy of fossils , or from molecular clock estimates. Viruses , and particularly RNA viruses form clades. These are useful in tracking
1210-776: A close relationship with its mother for several years more. 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. The biggest threats to the chimpanzee are habitat loss, poaching, and disease. Chimpanzees appear in Western popular culture as stereotyped clown-figures and have featured in entertainments such as chimpanzees' tea parties , circus acts and stage shows. Although chimpanzees have been kept as pets, their strength, aggressiveness, and unpredictability makes them dangerous in this role. Some hundreds have been kept in laboratories for research, especially in
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#17329304074711320-534: A coalition allows males to dominate a third individual when they could not by themselves, as politically apt chimpanzees can exert power over aggressive interactions regardless of their rank. Coalitions can also give an individual male the confidence to challenge a dominant or larger 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 suddenly turn on another if it
1430-464: A consortship and mate outside their community. In addition, females sometimes leave their community 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 chimpanzee communities in some areas, and the victims are often consumed. Male chimpanzees practice infanticide on unrelated young to shorten
1540-495: A dark muddy colour in eastern chimpanzees, freckled on white which ages to a heavily mottled muddy colour in central chimpanzees, and black with a butterfly-shaped white mask that darkens with age in western chimpanzees. Facial pigmentation increases with age and exposure to ultraviolet light. Females develop swelling pink skin when in oestrus. Chimpanzees are adapted for both arboreal and terrestrial locomotion . Arboreal locomotion consists of vertical climbing and brachiation . On
1650-798: A dying or dead group member. When witnessing a sudden death, the other group members act in frenzy, with vocalisations, aggressive displays, and touching of the corpse. In one case chimpanzees cared for a dying elder, then attended and cleaned the corpse. Afterward, they avoided the spot where the elder died and behaved in a more subdued manner. Mothers have been reported to carry around and groom their dead infants for several days. Experimenters now and then witness behaviour that cannot be readily reconciled with chimpanzee intelligence or theory of mind . Wolfgang Köhler , for instance, reported insightful behaviour in chimpanzees, but he likewise often observed that they experienced "special difficulty" in solving simple problems. Researchers also reported that, when faced with
1760-413: A female chimpanzee were to participate in the hunting group and catch a Red Colobus, it would likely immediately be taken by an adult male. Female chimpanzees are estimated to hunt ≈ 10-15% of a community's vertebrates. Chimpanzees display numerous signs of intelligence, from the ability to remember symbols to cooperation, tool use, and varied language capabilities . They are among species that have passed
1870-437: A few individuals. These groups may consist of any combination of age and sexes. Both males and females sometimes travel alone. This fission–fusion society may include groups of four types: all-male, adult females and offspring, adults of both sexes, or one female and her offspring. These smaller groups emerge in a variety of types, for a variety of purposes. For example, an all-male troop may be organised to hunt for meat, while
1980-414: A group consisting of lactating females serves to act as a "nursery group" for the young. At the core of social structures are males, which patrol the territory, protect group members, and search for food. Males remain in their natal communities, while females generally emigrate at adolescence. Males in a community are more likely to be related to one another than females are to each other. Among males, there
2090-452: A hand. When in an aggressive mode, a chimpanzee swaggers bipedally, hunched over and arms waving, in an attempt to exaggerate its size. While travelling, chimpanzees keep in contact by beating their hands and feet against the trunks of large trees, an act that is known as "drumming". They also do this when encountering individuals from other communities. Vocalisations are also important in chimpanzee communication. The most common call in adults
2200-566: A leopard cub after mobbing it and its mother in their den. Four chimpanzees could have fallen prey to lions at Mahale Mountains National Park . Although no other instances of lion predation on chimpanzees have been recorded, lions likely do kill chimpanzees occasionally, and the larger group sizes of savanna chimpanzees may have developed as a response to threats from these big cats. Chimpanzees may react to lions by fleeing up trees, vocalising, or hiding in silence. Chimpanzees and humans share only 50% of their parasite and microbe species. This
2310-448: A new group if accompanied by immigrant females who have an existing relationship with this male. This gives the resident males reproductive advantages with these females, as they are more inclined to remain in the group if their male friend is also accepted. Chimpanzees use facial expressions, postures, and sounds to communicate with each other. Chimpanzees have expressive faces that are important in close-up communications. When frightened,
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#17329304074712420-508: A pronounced brow ridge . It has forward-facing eyes, a small nose, rounded non-lobed ears and a long mobile upper lip. Additionally, adult males have sharp canine teeth. Like all great apes, it has a dental formula of 2.1.2.3 2.1.2.3 , that is, two incisors , one canine , two premolars , and three molars on both halves of each jaw. Chimpanzees lack the prominent sagittal crest and associated head and neck musculature of gorillas. Chimpanzee bodies are covered by coarse hair, except for
2530-613: A remarkably long adolescence, not being weaned for several years, and not becoming fully mature for eight to thirteen years in most species (longer in orangutans and humans). As a result, females typically give birth only once every few years. There is no distinct breeding season. Gorillas and chimpanzees live in family groups of around five to ten individuals, although much larger groups are sometimes noted. Chimpanzees live in larger groups that break up into smaller groups when fruit becomes less available. When small groups of female chimpanzees go off in separate directions to forage for fruit,
2640-405: 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 with each other and congregate into parties in a particular area. Male chimpanzees exist in a linear dominance hierarchy . Top-ranking males tend to be aggressive even during dominance stability. This
2750-422: A revised taxonomy based on a concept strongly resembling clades, although the term clade itself would not be coined until 1957 by his grandson, Julian Huxley . German biologist Emil Hans Willi Hennig (1913–1976) is considered to be the founder of cladistics . He proposed a classification system that represented repeated branchings of the family tree, as opposed to the previous systems, which put organisms on
2860-429: A suffix added should be e.g. "dracohortian". A clade is by definition monophyletic , meaning that it contains one ancestor which can be an organism, a population, or a species and all its descendants. The ancestor can be known or unknown; any and all members of a clade can be extant or extinct. The science that tries to reconstruct phylogenetic trees and thus discover clades is called phylogenetics or cladistics ,
2970-476: A theory of mind. This is also the case for some New World monkeys outside the family of great apes, as, for example, the capuchin monkeys . However, even without the ability to test whether early members of the Hominini (such as Homo erectus , Homo neanderthalensis , or even the australopithecines) had a theory of mind, it is difficult to ignore similarities seen in their living cousins. Orangutans have shown
3080-741: A varied use of the word "hominid" over time. The original meaning of the term referred to only humans and their closest relatives—what is now the modern meaning of the term " hominin ". The meaning of the taxon Hominidae changed gradually, leading to a modern usage of "hominid" that includes all the great apes including humans. A number of very similar words apply to related classifications: A cladogram indicating common names (cf. more detailed cladogram below ): Hylobatidae gibbons Pongo abelii Pongo tapanuliensis Pongo pygmaeus Gorilla gorilla Gorilla beringei Pan troglodytes Pan paniscus Homo sapiens humans Hominidae
3190-419: Is Oreopithecus , from the fossil-rich coal beds in northern Italy and dated to 9 million years ago. Molecular evidence indicates that the lineage of gibbons (family Hylobatidae), the "lesser apes", diverged from that of the great apes some 18–12 million years ago, and that of orangutans (subfamily Ponginae) diverged from the other great apes at about 12 million years. There are no fossils that clearly document
3300-728: Is 2.1.2.3 2.1.2.3 . Human teeth and jaws are markedly smaller relative to body size compared to those of other apes. This may be an adaptation not only to the extensive use of tools, which has supplanted the role of jaws in hunting and fighting, but also to eating cooked food since the end of the Pleistocene . Although most living species are predominantly quadrupedal , they are all able to use their hands for gathering food or nesting materials, and, in some cases, for tool use. They build complex sleeping platforms, also called nests, in trees to sleep in at night, but chimpanzees and gorillas also build terrestrial nests, and gorillas can also sleep on
3410-812: Is abundant, gorilla and chimpanzee diets converge, but when fruit is scarce gorillas resort to vegetation. The two apes may also feed on different species, whether fruit or insects. Interactions between them can range from friendly and even stable social bonding, to avoidance, to aggression and even predation of infants on the part of chimpanzees. The average lifespan of a wild chimpanzee is relatively short. They usually live less than 15 years, although individuals that reach 12 years may live an additional 15 years. On rare occasions, wild chimpanzees may live nearly 60 years. Captive chimpanzees tend to live longer than most wild ones, with median lifespans of 31.7 years for males and 38.7 years for females. The oldest-known male captive chimpanzee to have been documented lived to 66 years, and
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3520-499: Is also used with a similar meaning in other fields besides biology, such as historical linguistics ; see Cladistics § In disciplines other than biology . The term "clade" was coined in 1957 by the biologist Julian Huxley to refer to the result of cladogenesis , the evolutionary splitting of a parent species into two distinct species, a concept Huxley borrowed from Bernhard Rensch . Many commonly named groups – rodents and insects , for example – are clades because, in each case,
3630-439: Is brief, lasting approximately seven seconds. The gestation period is eight months. 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 chimpanzee's future rank may be dependent on its mother's status. Male chimpanzees continue to associate with
3740-530: Is documented in wild and captive chimpanzees. 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. 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. Chimpanzees have displayed different behaviours in response to
3850-678: Is due to the differences in environmental and dietary adaptations; human internal parasite species overlap more with omnivorous, savanna-dwelling baboons. The chimpanzee is host to the louse species Pediculus schaeffi , a close relative of P. 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 gastro intestinal parasites of wild chimpanzees in degraded forest in Uganda found nine species of protozoa , five nematodes , one cestode , and one trematode . The most prevalent species
3960-463: 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 caused mainly by the large measure of individual autonomy that individuals have within their fission-fusion social groups. As
4070-471: Is in turn included in the mammal, vertebrate and animal clades. The idea of a clade did not exist in pre- Darwinian Linnaean taxonomy , which was based by necessity only on internal or external morphological similarities between organisms. Many of the better known animal groups in Linnaeus's original Systema Naturae (mostly vertebrate groups) do represent clades. The phenomenon of convergent evolution
4180-436: Is made by young chimpanzees as a form of begging or when lost from the group. Chimpanzees 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 , chimpanzees hunt where the forest canopy is interrupted or irregular. This allows them to easily corner
4290-403: Is more robustly built than the bonobo but less than the gorilla . The arms of a chimpanzee are longer than its legs and can reach below the knees. The hands have long fingers with short thumbs and flat fingernails. The feet are adapted for grasping, and the big toe is opposable . The pelvis is long with an extended ilium . A chimpanzee's head is rounded with a prominent and prognathous face and
4400-533: Is much greater than that between male and female chimpanzees. This enables gorilla males to physically dominate female gorillas more easily. In both chimpanzees and gorillas, the groups include at least one dominant male, and young males leave the group at maturity. Due to the close genetic relationship between humans and the other great apes, certain animal rights organizations, such as the Great Ape Project , argue that nonhuman great apes are persons and, per
4510-654: Is probably due to the chimpanzee's fission-fusion society, with male chimpanzees leaving groups and returning after extended periods of time. With this, a dominant male is unsure if any "political maneuvering" has occurred in his absence and must re-establish his dominance. Thus, a large amount of aggression occurs within five to fifteen minutes after a reunion. During these encounters, displays of aggression are generally preferred over physical attacks. Males maintain and improve their social ranks by forming coalitions, which have been characterised as "exploitative" and based on an individual's influence in agonistic interactions. Being in
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4620-515: Is responsible for many cases of misleading similarities in the morphology of groups that evolved from different lineages. With the increasing realization in the first half of the 19th century that species had changed and split through the ages, classification increasingly came to be seen as branches on the evolutionary tree of life . The publication of Darwin's theory of evolution in 1859 gave this view increasing weight. In 1876 Thomas Henry Huxley , an early advocate of evolutionary theory, proposed
4730-489: Is still controversial. As an example, see the full current classification of Anas platyrhynchos (the mallard duck) with 40 clades from Eukaryota down by following this Wikispecies link and clicking on "Expand". The name of a clade is conventionally a plural, where the singular refers to each member individually. A unique exception is the reptile clade Dracohors , which was made by haplology from Latin "draco" and "cohors", i.e. "the dragon cohort "; its form with
4840-477: Is the " pant-hoot ", which may signal social rank and bond along with keeping groups together. Pant-hoots are made of four parts, starting with soft "hoos", the introduction; that gets louder and louder, the build-up; and climax into screams and sometimes barks; these die down back to soft "hoos" during the letdown phase as the call ends. Grunting is made in situations like feeding and greeting. Submissive individuals make "pant-grunts" towards their superiors. Whimpering
4950-432: Is to his advantage. Low-ranking males frequently switch sides in disputes between more dominant individuals. Low-ranking males benefit from an unstable hierarchy and often find increased sexual opportunities if a dispute or conflict occurs. 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,
5060-549: The Declaration on Great Apes , should be given basic human rights . In 1999, New Zealand was the first country to ban any great ape experimentation, and now 29 countries have currently instituted a research ban to protect great apes from any kind of scientific testing. On 25 June 2008, the Spanish parliament supported a new law that would make "keeping apes for circuses, television commercials or filming" illegal. On 8 September 2010,
5170-699: The European Union banned the testing of great apes . The following table lists the estimated number of great ape individuals living outside zoos. Below is a cladogram with extinct species. It is indicated approximately how many million years ago (Mya) the clades diverged into newer clades. Kenyapithecus (†13 Mya) Sivapithecus (†9) Crown Ponginae Ankarapithecus (†9) Giganthopithecus (†0.1) Khoratpithecus (†7) Pierolapithecus (†11) Hispanopithecus (†10) Lufengpithecus (†7) Khoratpithecus (†9) Ardipithecus (incl. Homo ) Clade In biological phylogenetics ,
5280-615: The Greek god , while the specific name troglodytes was taken from the Troglodytae , a mythical race of cave-dwellers. The first great ape known to Western science in the 17th century was the " orang-outang " (genus Pongo ), the local Malay name being recorded in Java by the Dutch physician Jacobus Bontius . In 1641, the Dutch anatomist Nicolaes Tulp applied the name to a chimpanzee or bonobo brought to
5390-471: The Middle Pleistocene . According to studies published in 2017 by researchers at George Washington University , bonobos, along with chimpanzees, split from the human line about 8 million years ago; then bonobos split from the common chimpanzee line about 2 million years ago. Another 2017 genetic study suggests ancient gene flow ( introgression ) between 200,000 and 550,000 years ago from the bonobo into
5500-506: The Neolithic Revolution , have consumed mostly cereals and other starchy foods, including increasingly highly processed foods , as well as many other domesticated plants (including fruits) and meat . Gestation in great apes lasts 8–9 months, and results in the birth of a single offspring, or, rarely, twins. The young are born helpless, and require care for long periods of time. Compared with most other mammals, great apes have
5610-479: The great apes or hominids ( / ˈ h ɒ m ɪ n ɪ d z / ), are a taxonomic family of primates that includes eight extant species in four genera : Pongo (the Bornean , Sumatran and Tapanuli orangutan ); Gorilla (the eastern and western gorilla ); Pan (the chimpanzee and the bonobo ); and Homo , of which only modern humans ( Homo sapiens ) remain. Numerous revisions in classifying
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#17329304074715720-632: The mirror test , suggesting self-awareness . In one study, two young chimpanzees showed retention of mirror self-recognition after one year without access to mirrors. Chimpanzees have been observed to use insects to treat their own wounds and those of others. They catch them and apply them directly to the injury. Chimpanzees also display signs of culture among groups, with the learning and transmission of variations in grooming, tool use and foraging techniques leading to localized traditions. A 30-year study at Kyoto University 's Primate Research Institute has shown that chimpanzees are able to learn to recognise
5830-407: The robust chimpanzee . The chimpanzee and the bonobo are the only species in the genus Pan . Evidence from fossils and DNA sequencing shows that Pan is a sister taxon to the human lineage and is thus humans ' closest living relative. 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 larger and more robust than
5940-698: The Gombe group. A study published in 2010 found that the chimpanzees wage wars over territory, not mates. Patrols from smaller groups are more likely to avoid contact with their neighbours. Patrols from large groups even take over a smaller group's territory, gaining access to more resources, food, and females. While it was traditionally accepted that only female chimpanzees immigrate and males remain in their natal troop for life, there are confirmed cases of adult males safely integrating themselves into new communities among West African chimpanzees, suggesting they are less territorial than other subspecies. Chimpanzees mate throughout
6050-532: The Netherlands from Angola. Another Dutch anatomist, Peter Camper , dissected specimens from Central Africa and Southeast Asia in the 1770s, noting the differences between the African and Asian apes. The German naturalist Johann Friedrich Blumenbach classified the chimpanzee as Simia troglodytes by 1775. Another German naturalist, Lorenz Oken , coined the genus Pan in 1816. The bonobo was recognised as distinct from
6160-479: The United States. Many attempts have been made to teach languages such as American Sign Language to chimpanzees, with limited success. The English word chimpanzee is first recorded in 1738. It is derived from Vili ci-mpenze or Tshiluba language chimpenze , with a meaning of " ape ", or "mockman". The colloquialism "chimp" was most likely coined some time in the late 1870s. The genus name Pan derives from
6270-441: The aggressive data came, Gombe and Mahale, used artificial feeding systems that increased aggression in the chimpanzee populations studied. Thus, the behaviour may 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 chimpanzees patrolling the borders of their territory, brutally attacking chimpanzees that had split off from
6380-421: The ancestors of central and eastern chimpanzees. Four subspecies of the chimpanzee have been recognised, with the possibility of a fifth: A draft version of the chimpanzee genome was published in 2005 and encodes 18,759 proteins, (compared to 20,383 in the human proteome). The DNA sequences of humans and chimpanzees are very similar and the difference in protein number mostly arises from incomplete sequences in
6490-623: The ancestry of gibbons, which may have originated in a still-unknown South East Asian hominoid population; but fossil proto-orangutans, dated to around 10 million years ago, may be represented by Sivapithecus from India and Griphopithecus from Turkey. Species close to the last common ancestor of gorillas, chimpanzees and humans may be represented by Nakalipithecus fossils found in Kenya and Ouranopithecus fossils found in Greece . Molecular evidence suggests that between 8 and 4 million years ago, first
6600-490: The bare ground. All species are omnivorous , although chimpanzees and orangutans primarily eat fruit. When gorillas run short of fruit at certain times of the year or in certain regions, they resort to eating shoots and leaves, often of bamboo , a type of grass. Gorillas have extreme adaptations for chewing and digesting such low-quality forage, but they still prefer fruit when it is available, often going miles out of their way to find especially preferred fruits. Humans, since
6710-412: The bonobo, weighing 40–70 kg (88–154 lb) for males and 27–50 kg (60–110 lb) for females and standing 150 cm (4 ft 11 in). The chimpanzee lives in groups that 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 strict male-dominated hierarchy, where disputes are generally settled without
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#17329304074716820-634: The chimpanzee by 1933. Despite a large number of Homo fossil finds, Pan fossils 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, but chimpanzee fossils have now been reported from Kenya. This indicates that both humans and members of the Pan clade were present in the East African Rift Valley during
6930-424: The chimpanzee genome. Both species differ by about 35 million single-nucleotide changes, five million insertion/deletion events and various chromosomal rearrangements . Typical human and chimpanzee protein homologs differ in an average of only two amino acids . About 30% of all human proteins are identical in sequence to the corresponding chimpanzee protein. Duplications of small parts of chromosomes have been
7040-479: The chimpanzee inhabits multistage secondary deciduous forest , which has grown after shifting cultivation , as well as primary forest and grassland. At Taï , it is 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 builds a sleeping nest in a tree in a different location each night, never using
7150-424: The chimpanzees and the gorillas to the genus Homo along with humans.) But, those fossil relatives more closely related to humans than the chimpanzees represent the especially close members of the human family, and without necessarily assigning subfamily or tribal categories. Many extinct hominids have been studied to help understand the relationship between modern humans and the other extant hominids. Some of
7260-399: The development of culture comparable to that of chimpanzees, and some say the orangutan may also satisfy those criteria for the theory of mind concept. These scientific debates take on political significance for advocates of great ape personhood . The great apes are tailless primates, with the smallest living species being the bonobo at 30 to 40 kilograms (66 to 88 lb) in weight, and
7370-418: The dominant males can no longer control them and the females often mate with other subordinate males. In contrast, groups of gorillas stay together regardless of the availability of fruit. When fruit is hard to find, they resort to eating leaves and shoots. This fact is related to gorillas' greater sexual dimorphism relative to that of chimpanzees; that is, the difference in size between male and female gorillas
7480-607: The drier environments outside the African equatorial belt; and there they encountered antelope, hyenas, elephants and other forms becoming adapted to surviving in the East African savannas , particularly the regions of the Sahel and the Serengeti . The wet equatorial belt contracted after about 8 million years ago, and there is very little fossil evidence for the divergence of the hominin lineage from that of gorillas and chimpanzees—which split
7590-654: The early Miocene , about 22 million years ago, there were many species of tree-adapted primitive catarrhines from East Africa; the variety suggests a long history of prior diversification. Fossils from 20 million years ago include fragments attributed to Victoriapithecus , the earliest Old World monkey. Among the genera thought to be in the ape lineage leading up to 13 million years ago are Proconsul , Rangwapithecus , Dendropithecus , Limnopithecus , Nacholapithecus , Equatorius , Nyanzapithecus , Afropithecus , Heliopithecus , and Kenyapithecus , all from East Africa. At sites far distant from East Africa,
7700-402: The extinct members of this family include Gigantopithecus , Orrorin , Ardipithecus , Kenyanthropus , and the australopithecines Australopithecus and Paranthropus . The exact criteria for membership in the tribe Hominini under the current understanding of human origins are not clear, but the taxon generally includes those species that share more than 97% of their DNA with
7810-403: The face, fingers, toes, palms of the hands, and soles of the feet. Chimpanzees lose more hair as they age and develop bald spots. The hair of a chimpanzee is typically black but can be brown or ginger. As they get older, white or grey patches may appear, particularly on the chin and lower region. Chimpanzee skin that is covered with body hair is white, while exposed areas vary: white which ages into
7920-438: The family Hylobatidae (the gibbons ), perhaps 15 to 20 million years ago. Due to the close genetic relationship between humans and the other great apes, certain animal rights organizations, such as the Great Ape Project , argue that nonhuman great apes are persons and should be given basic human rights . Twenty-nine countries have instituted research bans to protect great apes from any kind of scientific testing. In
8030-496: The females they impregnated and interact with and support their offspring. Newborn chimpanzees are helpless. For example, their grasping reflex is not strong enough to support them for more than a few seconds. For their first 30 days, infants cling to their mother's bellies. 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
8140-451: The fundamental unit of cladistics , a modern approach to taxonomy adopted by most biological fields. The common ancestor may be an individual, a population , or a species ( extinct or extant ). Clades are nested, one in another, as each branch in turn splits into smaller branches. These splits reflect evolutionary history as populations diverged and evolved independently. Clades are termed monophyletic (Greek: "one clan") groups. Over
8250-512: The gorillas (genus Gorilla ), and then the chimpanzees (genus Pan ) split off from the line leading to humans. Human DNA is approximately 98.4% identical to that of chimpanzees when comparing single nucleotide polymorphisms (see human evolutionary genetics ). The fossil record, however, of gorillas and chimpanzees is limited; both poor preservation—rain forest soils tend to be acidic and dissolve bone—and sampling bias probably contribute most to this problem. Other hominins probably adapted to
8360-400: The great apes have caused the use of the term hominid to change over time. The original meaning of "hominid" referred only to humans ( Homo ) and their closest extinct relatives. However, by the 1990s humans and other apes were considered to be "hominids". The earlier restrictive meaning has now been largely assumed by the term hominin , which comprises all members of the human clade after
8470-472: The grip strength of an adult chimpanzee is estimated to be 200 kg (440 lb), while other sources claim figures of up to 330 kg (730 lb). The 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 mostly uses semideciduous and evergreen forest as well as open woodland. At Bossou ,
8580-477: The ground, chimpanzees move both quadrupedally and bipedally. These movements appear to have similar energy costs. As with bonobos and gorillas, chimpanzees move quadrupedally by knuckle-walking , which probably evolved independently in Pan and Gorilla . Their muscles are 50% stronger per weight than those of humans due to higher content of fast twitch muscle fibres , one of the chimpanzee's adaptations for climbing and swinging. According to Japan's Asahiyama Zoo ,
8690-546: The group consists of a common ancestor with all its descendant branches. Rodents, for example, are a branch of mammals that split off after the end of the period when the clade Dinosauria stopped being the dominant terrestrial vertebrates 66 million years ago. The original population and all its descendants are a clade. The rodent clade corresponds to the order Rodentia, and insects to the class Insecta. These clades include smaller clades, such as chipmunk or ant , each of which consists of even smaller clades. The clade "rodent"
8800-450: The honey out of the hive if the bees are stingless . For hives of the dangerous African honeybees , chimpanzees use longer and thinner sticks to extract the honey. Chimpanzees also fish for ants using the same tactic. Ant dipping is difficult and some chimpanzees never master it. West African chimpanzees crack open hard nuts with stones or branches. Some forethought in this activity is apparent, as these tools are not found together or where
8910-410: The humans, chimpanzees, and gorillas in the subfamily Homininae ; others with orangutans in the subfamily Ponginae (see classification graphic below). The most recent common ancestor of all Hominidae lived roughly 14 million years ago, when the ancestors of the orangutans speciated from the ancestral line of the other three genera. Those ancestors of the family Hominidae had already speciated from
9020-457: The interbirth intervals in the females. Females sometimes practice infanticide. This may be related to the dominance hierarchy in females or may simply be pathological. Inbreeding was studied in a relatively undisturbed eastern bisexual chimpanzee community. Despite an increased inbreeding risk incurred by females who do not disperse before reaching reproductive age, these females were still able to avoid producing inbred offspring. Copulation
9130-529: The lack of complexity, forethought and skill are apparent in making these tools. Chimpanzees have used stone tools since at least 4,300 years ago. A 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, chimpanzees simply use their hands to extract termites. When foraging for honey, chimpanzees use modified short sticks to scoop
9240-453: The largest being the eastern gorillas, with males weighing 140 to 180 kilograms (310 to 400 lb). In all great apes, the males are, on average, larger and stronger than the females, although the degree of sexual dimorphism varies greatly among species. Hominid teeth are similar to those of the Old World monkeys and gibbons, although they are especially large in gorillas. The dental formula
9350-590: The last few decades, the cladistic approach has revolutionized biological classification and revealed surprising evolutionary relationships among organisms. Increasingly, taxonomists try to avoid naming taxa that are not clades; that is, taxa that are not monophyletic . Some of the relationships between organisms that the molecular biology arm of cladistics has revealed include that fungi are closer relatives to animals than they are to plants, archaea are now considered different from bacteria , and multicellular organisms may have evolved from archaea. The term "clade"
9460-518: The latter term coined by Ernst Mayr (1965), derived from "clade". The results of phylogenetic/cladistic analyses are tree-shaped diagrams called cladograms ; they, and all their branches, are phylogenetic hypotheses. Three methods of defining clades are featured in phylogenetic nomenclature : node-, stem-, and apomorphy-based (see Phylogenetic nomenclature§Phylogenetic definitions of clade names for detailed definitions). The relationship between clades can be described in several ways: The age of
9570-721: The major source of differences between human and chimpanzee genetic material; about 2.7% of the corresponding modern genomes represent differences, produced by gene duplications or deletions, since humans and chimpanzees diverged from their common evolutionary ancestor. Adult chimpanzees have an average standing height of 150 cm (4 ft 11 in). Wild adult males weigh between 40 and 70 kg (88 and 154 lb), and females weigh between 27 and 50 kg (60 and 110 lb). In exceptional cases, certain individuals may considerably exceed these measurements, standing over 168 cm (5 ft 6 in) on two legs and weighing up to 136 kg (300 lb) in captivity. The chimpanzee
9680-526: 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. Jane Goodall documented many occasions within Gombe Stream National Park of chimpanzees and western red colobus monkeys ignoring each other despite close proximity. Chimpanzees do not appear to directly compete with gorillas in areas where they overlap. When fruit
9790-501: The modern human genome , and exhibit a capacity for language or for simple cultures beyond their 'local family' or band. The theory of mind concept—including such faculties as empathy, attribution of mental state, and even empathetic deception—is a controversial criterion; it distinguishes the adult human alone among the hominids. Humans acquire this capacity after about four years of age, whereas it has not been proven (nor has it been disproven) that gorillas or chimpanzees ever develop
9900-407: The monkeys when chasing them in the appropriate direction. Chimpanzees may also hunt as a coordinated team, so that they can corner their prey even in a continuous canopy. During an arboreal hunt, each chimpanzee 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
10010-410: The need for violence. Nearly all chimpanzee populations have been recorded using tools , modifying sticks, rocks, grass and leaves and using them for hunting and acquiring honey , termites , ants , nuts and water. The species has also been found creating sharpened sticks to spear small mammals. Its gestation period is eight months. The infant is weaned at about three years old but usually maintains
10120-405: The numbers 1 to 9 and their values. The chimpanzees further show an aptitude for eidetic memory , demonstrated in experiments in which the jumbled digits are flashed onto a computer screen for less than a quarter of a second. One chimpanzee, Ayumu , was able to correctly and quickly point to the positions where they appeared in ascending order. Ayumu performed better than human adults who were given
10230-621: The nuts are collected. Nut cracking is also difficult and must be learned. Chimpanzees also use leaves as sponges or spoons to drink water. West African chimpanzees in Senegal were found to sharpen sticks with their teeth, which were then 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 . Whilst experimental studies on captive chimpanzees have found that many of their species-typical tool-use behaviours can be individually learnt by each chimpanzees,
10340-404: The oldest female, Little Mama , was nearly 80 years old. Leopards prey on chimpanzees in some areas. It is possible that much of the mortality caused by leopards can be attributed to individuals that have specialised in killing chimpanzees. Chimpanzees may react to a leopard's presence with loud vocalising, branch shaking, and throwing objects. There is at least one record of chimpanzees killing
10450-594: The presence of other generalized non- cercopithecids , that is, non-monkey primates, of middle Miocene age— Otavipithecus from cave deposits in Namibia, and Pierolapithecus and Dryopithecus from France, Spain and Austria—is further evidence of a wide diversity of ancestral ape forms across Africa and the Mediterranean basin during the relatively warm and equable climatic regimes of the early and middle Miocene. The most recent of these far-flung Miocene apes ( hominoids )
10560-675: The rest of their first year. When they reach two years of age, they are able to move and sit independently and start moving beyond the arms' reach of their mothers. By four to six years, chimpanzees are weaned and infancy ends. The juvenile period for chimpanzees lasts from their sixth to ninth years. Juveniles remain close to their mothers, but interact an increasing amount 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. A captive study suggests males can safely immigrate to
10670-639: The same nest more than once. Chimpanzees sleep alone in separate nests except for infants or juvenile chimpanzees, which sleep with their mothers. The chimpanzee is an omnivorous frugivore . It prefers fruit above all other food, but it also eats leaves, leaf buds, seeds, blossoms, stems, pith , bark, and resin . A study in Budongo Forest , Uganda found that 64.5% of their feeding time concentrated on fruits (84.6% of which being ripe), particularly those from two species of Ficus , Maesopsis eminii , and Celtis gomphophylla . In addition, 19% of feeding time
10780-553: The same test. In controlled experiments on cooperation , chimpanzees show a basic understanding of cooperation, and 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 behaviours. Great apes show laughter-like vocalisations in response to physical contact, such as wrestling, play chasing, or tickling . This
10890-422: The split from the chimpanzees ( Pan ). The current meaning of "hominid" includes all the great apes including humans. Usage still varies, however, and some scientists and laypersons still use "hominid" in the original restrictive sense; the scholarly literature generally shows the traditional usage until the turn of the 21st century. Within the taxon Hominidae, a number of extant and extinct genera are grouped with
11000-448: The status of an adult female may be important for her offspring. Females in Taï have also been recorded to form alliances. While chimpanzee social structure is often referred to as patriarchal , it is not entirely unheard of for females to forge coalitions against males. There is also at least one recorded case of females securing a dominant position over males in their respective troop, albeit in
11110-564: The top of preferred mammal prey. Other mammalian prey include red-tailed monkeys , infant and juvenile yellow baboons , bush babies , blue duikers , bushbucks , and common warthogs . Despite the fact that chimpanzees are known to hunt and to collect both insects and other invertebrates, such food actually makes up a very small 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,
11220-483: The trees and climb up to block prey that takes 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 colobus monkeys will attack the hunting chimps. When caught and killed, the meal is distributed to all hunting party members and even bystanders. Male chimpanzees hunt in groups more than females. Female chimpanzees tend to hunt solitarily. If
11330-494: The use of Pongidae to be restricted to just one closely related grouping. Thus, many biologists now assign Pongo (as the sub family Ponginae ) to the family Hominidae. The taxonomy shown here follows the monophyletic groupings according to the modern understanding of human and great ape relationships. Humans and close relatives including the tribes Hominini and Gorillini form the subfamily Homininae (see classification graphic below). (A few researchers go so far as to refer
11440-514: The year, although the number of females in oestrus varies seasonally in a group. Female chimpanzees are more likely to come into oestrus when food is readily available. Oestrous females exhibit sexual swellings . Chimpanzees are promiscuous : during oestrus, females mate with several males in their community, while males have large testicles for sperm competition . Other forms of mating also exist. A community's dominant males sometimes restrict reproductive access to females. A male and female can form
11550-415: Was happening both before and after Nim's signs). In the reanalysis, Terrace and Bever concluded that 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
11660-538: Was not like human language acquisition . Nim never initiated conversations himself, rarely introduced new words, and mostly 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. Hominidae sister: Hylobatidae The Hominidae ( / h ɒ ˈ m ɪ n ɪ d iː / ), whose members are known as
11770-554: Was originally the name given to the family of humans and their (extinct) close relatives, with the other great apes (that is, the orangutans, gorillas and chimpanzees) all being placed in a separate family, the Pongidae . However, that definition eventually made Pongidae paraphyletic because at least one great ape species (the chimpanzees) proved to be more closely related to humans than to other great apes. Most taxonomists today encourage monophyletic groups—this would require, in this case,
11880-403: Was spent on arboreal leaves, mostly Broussonetia papyrifera and Celtis mildbraedii . While the chimpanzee is mostly herbivorous , it does eat honey, soil, insects, birds and their eggs, and small to medium-sized mammals, including other primates. Insect species consumed include the weaver ant Oecophylla longinoda , Macrotermes termites , and honey bees . The red colobus ranks at
11990-462: Was the protozoan Troglodytella abrassarti . Recent studies have suggested that human observers influence chimpanzee behaviour. One suggestion is that drones , camera traps, and remote microphones should be used to record and monitor chimpanzees rather than direct human observation. Chimpanzees live in communities that typically range from around 15 to more than 150 members but spend most of their time traveling in small, temporary groups consisting of
12100-403: Was thought to have occurred around that time. The earliest fossils argued by some to belong to the human lineage are Sahelanthropus tchadensis (7 Ma) and Orrorin tugenensis (6 Ma), followed by Ardipithecus (5.5–4.4 Ma), with species Ar. kadabba and Ar. ramidus . The classification of the great apes has been revised several times in the last few decades; these revisions have led to
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