Chimpanzee, sometimes colloquially chimp, is
the common name for the two extant species of ape in the genus
Pan. The Congo River forms the boundary between
the native habitat of the two species:
- Common Chimpanzee, Pan troglodytes (West and
- Bonobo, Pan paniscus (forests of the Democratic
Republic of the Congo)
Chimpanzees are members of the Hominidae family, along with
gorillas, humans, and orangutans. Chimpanzees split from human
evolution about 6 million years ago and the two chimpanzee
species are the closest living relatives to humans, all being
members of the Hominini tribe (along with extinct species of
Hominina subtribe). Chimpanzees are the only known members of
the Panina subtribe. The two Pan species split
only about one million years ago.
The genus Pan is considered to be part of the
subfamily Homininae to which humans also belong. These two
species are the closest living evolutionary relatives to humans,
sharing a common ancestor with humans six million years ago.
Research by Mary-Claire King in 1973 found 99% identical DNA
between human beings and chimpanzees,
although research since has modified that finding to about 94%
commonality, with some of the difference occurring in non-coding
It has been proposed that troglodytes and paniscus
belong with sapiens in the genus Homo, rather than
in Pan. One of the arguments for this is that other
species have been reclassified to belong to the same genus on
the basis of less genetic similarity than that between humans
A lot of human fossils have been found, but chimpanzee
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. 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
Anatomy and physiology
The male common chimp is up to 1.7 metres (5.6 ft) high when
standing, and weighs as much as 70 kilograms (150 lb); the
female is somewhat smaller. The common chimp’s long arms, when
extended, have a span one and a half times as long as the body’s
height and a chimpanzee's arms are longer than its legs.
The bonobo is a little shorter and thinner than the common
chimpanzee but has longer limbs.
Both species use their long, powerful arms for climbing in
trees. On the ground, chimpanzees usually walk on all fours
using their knuckles for support with their hands clenched, a
form of locomotion called knuckle-walking. Chimpanzee feet are
better suited for walking than are those of the orangutan
because the chimp’s soles are broader and the toes shorter. Both
the common chimpanzee and bonobo can walk upright on two legs
when carrying objects with their hands and arms. The Bonobo has
proportionately longer upper limbs and tends to walk upright
more often than the Common Chimpanzee.
The coat is dark; the face, fingers, palms of the hands, and
soles of the feet are hairless; and the chimp has no tail. The
exposed skin of the face, hands and feet varies from pink to
very dark in both species, but is generally lighter in younger
individuals, darkening as maturity is reached. A University of
Chicago Medical Centre study has found significant genetic
differences between chimpanzee populations.
A bony shelf over the eyes gives the forehead a receding
appearance, and the nose is flat. Although the jaws protrude,
the lips are thrust out only when a chimp pouts. The brain of a
chimpanzee is about half the size of the human brain.
Chimpanzee testicles are unusually large for their body size,
with a combined weight of about 4 ounces (110 g) compared to a
gorilla's 1 ounce (28 g) or a human's 1.5 ounces (43 g).
This is generally attributed to sperm competition due to the
polyandrous nature of chimpanzee mating behavior.
Chimpanzees reach puberty at an age of between 8 and 10 years,
and rarely live past age 40 in the wild, but have been known to
live more than 60 years in captivity.
|Young chimpanzees playing in the forest
Anatomical differences between the Common Chimpanzee and the
Bonobo are slight, but in sexual and social behaviour there are
marked differences. The Common Chimpanzee has an omnivorous
diet, a troop hunting culture based on beta males led by an
alpha male, and highly complex social relationships.
The Bonobo, on the other hand, has a mostly frugivorous diet
and an egalitarian, nonviolent, matriarchal, sexually receptive
Bonobos are well known to have frequent sex, with bisexuality
the norm for both males and females, and also to use sex to help
prevent and resolve conflicts. Different groups of chimpanzees
also have different cultural behaviour with preferences for
types of tools.
The Common Chimpanzee tends to display higher levels of
aggression than the Bonobo.
Chimpanzees live in large multi-male and multi-female social
groups called communities. Within a community there is a
definite social hierarchy which is dictated by the position of
an individual and the influence the individual has on others.
Chimpanzees live in a leaner hierarchy in which more than one
individual may be dominant enough to dominate other members of
Typically there is a dominant male referred to as the Alpha
male. The Alpha male is the highest-ranking male who controls
the group and maintains order during any disputes. In chimpanzee
society the 'dominant male' does not always have to be the
largest or strongest male but rather the most manipulative and
political male who can influence the goings on within a group.
Male chimpanzees typically attain dominance through cultivating
allies who will provide support for that individual in case of
future ambitions for power.
The alpha male regularly displays by making his normally slim
coat puffed up to increase view size and charge to look as
threatening and as powerful as possible. This serves to
intimidate other members in an attempt to hold on to power and
maintain authority, and it may be fundamental to the alpha
male's holding on to his status. Lower-ranking chimpanzees will
show respect by making submissive gestures in body language or
reaching out their hand while grunting. Female chimpanzees will
show deference to the alpha male by presenting their
Female chimpanzees also have a hierarchy which is influenced
by the position of a female individual within a group. In some
chimpanzee communities, the young females may inherit high
status from a high-ranking mother.
The females will also form allies to dominate lower-ranking
females. In contrast to males who have a main purpose of
acquiring dominant status for access to mating privileges and
sometimes violent domination of subordinates, females acquire
dominant status for access to resources such as food.
High-ranking females will often get first access to resources.
In general, both genders acquire dominant status to improve
social standing within a group.
Its often the females who choose the alpha male. For a male
chimpanzee to win the alpha status, he must gain acceptance from
the females in the community as they are the ones who actually
dictate the lifestyle: the females are the ones who ensure the
survival of the next generation; they have to make sure that
their group is going to places that supply them with enough
In some cases, a group of dominant females will oust an alpha
male who is not to their preference and rather back up the other
male who they see potential of leading the group as a successful
Chimpanzees make tools and use them to acquire foods and for
social displays; they have sophisticated hunting strategies
requiring cooperation, influence and rank; they are status
conscious, manipulative and capable of deception; they can learn
to use symbols and understand aspects of human language
including some relational syntax, concepts of number and
and they are capable of spontaneous planning for a future state
One of the most significant discoveries was in October 1960
when Jane Goodall observed the use of tools among chimpanzees.
Recent research indicates that chimpanzee stone tool use dates
to at least 4,300 years ago.
Chimpanzee tool usage includes digging into termite mounds with
a large stick tool, and then using a small stick that has been
altered to "fish" the termites out.
A recent study revealed the use of such advanced tools as
spears, with which Common Chimpanzees in Senegal sharpen with
their teeth and use to spear Senegal Bushbabies out of small
holes in trees.
Before the discovery of tool use in chimps, it was believed that
humans were the only species to make and use tools, but several
other tool-using species are now known.
Recent studies have shown that chimpanzees engage in
apparently altruistic behaviour within groups,
but are indifferent to the welfare of unrelated group members.
However in the wild it has been shown that chimpanzees have
adopted an orphan chimpanzee, sometimes ones that come from
other unrelated groups.
And in some rare cases even male chimps have been shown to
take care of abandoned infant chimps of an unrelated group,
however in most cases they would normally kill the infant.
Evidence for "chimpanzee spirituality" includes display of
mourning, "incipient romantic love", "rain dance", appreciation
of natural beauty such as a sunset over a lake, curiosity and
respect towards wildlife (such as the python, which is neither a
threat nor a food source to chimpanzees), empathy toward other
species (such as feeding turtles) and even "animism" or "pretend
play" in chimps cradling and grooming rocks or sticks.
Chimps communicate in a manner similar to human non-verbal
communication, using vocalizations, hand gestures, and facial
expressions. Research into the chimpanzee brain has revealed
that chimp communication activates an area of the chimp brain
that is in the same position as Broca's area, a language center
in the human brain.
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 Beatrice Gardner in the 1960s involved
spending 51 months teaching American Sign Language to a
chimpanzee named Washoe. The Gardners reported that Washoe
learned 151 signs, and that she had spontaneously taught them to
Over a longer period of time, Washoe learned over 800 signs.
There is ongoing debate among some scientists, notably Noam
Chomsky and 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
including one involving a chimpanzee named, in parody, Nim
Chimpsky, trained by Herbert Terrace of Columbia University.
Although his initial reports were quite positive, in November
1979, Terrace and his team 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 re-analysis, Terrace 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’ behavior is pure drill,” he said.
“Language still stands as an important definition of the human
In this reversal, Terrace now argued that 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. Nim’s sentences also did not grow
in length, unlike human children whose vocabulary and sentence
length show a strong positive correlation.
A 30-year study at Kyoto University’s Primate Research
Institute has shown that chimps are able to learn to recognize
the numbers 1–9 and their values. The chimps further show an
aptitude for photographic memory, demonstrated in experiments in
which the jumbled digits 1–9 are flashed onto a computer screen
for less than a quarter of a second, after which the chimp,
Ayumu, is able to correctly and quickly point to the positions
where they appeared in ascending order. The same experiment was
failed by world memory champion Ben Pridmore on most attempts.
Laughter might not be confined or unique to humans. The
differences between chimpanzee and human laughter may be the
result of adaptations that have evolved to enable human speech.
Self-awareness of one's situation as seen in the mirror test, or
the ability to identify with another's predicament (see mirror
neurons), are prerequisites for laughter, so animals may be
laughing in the same way that humans do.
Chimpanzees, gorillas, and orangutans show laughterlike
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 recognizable to humans as such, because it is generated
by alternating inhalations and exhalations that sound more like
breathing and panting.
There are instances in which non-human primates have been
reported to have expressed joy. One study analyzed and recorded
sounds made by human babies and Bonobos when tickled. It found
that 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.
Adult Common Chimpanzees, particularly males, can be very
aggressive. They are highly territorial and are known to kill
Chimpanzees also engage in targeted hunting of lower order
primates such as the red colobus
and bush babies,
and use the meat from these kills as a "social tool" within
In February 2009, after an incident in which a pet chimp named
Travis attacked and mutilated a woman in Stamford, Connecticut,
the U.S. House of Representatives approved a primate pet ban in
the United States.
Interactions with humans
Africans have had contact with chimpanzees for millennia.
Chimpanzees have been kept as pets for centuries 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
who are keeping them as pets.
The first recorded contact of Europeans with chimps took
place in present-day Angola during the 17th century. The diary
of Portuguese explorer Duarte Pacheco Pereira (1506), preserved
in the Portuguese National Archive (Torre do Tombo), is probably
the first European document to acknowledge that chimpanzees
built their own rudimentary tools.
The first use of the name "chimpanzee", however, did not
occur until 1738. The name is derived from a Tshiluba language
term "kivili-chimpenze", which is the local name for the animal
and translates loosely as "mockman" or possibly just "ape". The
colloquialism "chimp" was most likely coined some time in
the late 1870s.
Biologists applied Pan as the genus name of the animal.
Chimps as well as other apes had also been purported to have
been known to Western writers in ancient times, but mainly as
myths and legends on the edge of European and Arab societal
consciousness, mainly through fragmented and sketchy accounts of
European adventurers. Apes are mentioned variously by Aristotle,
as well as the English Bible, where they are described as having
been collected by Solomon. (1 Kings 10:22. However the Hebrew
word, qőf, may mean a monkey.) Apes are mentioned in the
Qur'an (7:166), where God tells Israelites who transgressed
Shabbat "Be ye apes".
The first of these early transcontinental chimpanzees came
from Angola and were presented as a gift to Frederick Henry,
Prince of Orange in 1640, and were followed by a few of its
brethren over the next several years. Scientists described these
first chimpanzees as "pygmies", and noted the animals' distinct
similarities to humans. The next two decades would see a number
of the creatures imported into Europe, mainly acquired by
various zoological gardens as entertainment for visitors.
Darwin's theory of natural selection (published in 1859)
spurred scientific interest in chimpanzees, as in much of life
science, leading eventually to numerous studies of the animals
in the wild and captivity. The observers of chimpanzees at the
time were mainly interested in behaviour as it related to that
This was less strictly and disinterestedly scientific
than it might sound, with much attention being focused on
whether or not the animals had traits that could be considered
'good'; the intelligence of chimpanzees was often significantly
exaggerated, as immortalized in Hugo Rheinhold's Affe mit
Schädel (see image, left). By the end of the 19th century
chimpanzees remained very much a mystery to humans, with very
little factual scientific information available.
The 20th century saw a new age of scientific research into
chimpanzee behaviour. Before 1960, almost nothing was known
about chimpanzee behaviour in their natural habitat. In July of
that year, Jane Goodall set out to Tanzania's Gombe forest to
live among the chimpanzees, where she primarily studied the
members of the Kasakela chimpanzee community.
Her discovery that chimpanzees made and used tools was
groundbreaking, as humans were previously believed to be the
only species to do so. The most progressive early studies on
chimpanzees were spearheaded primarily by Wolfgang Köhler and
Robert Yerkes, both of whom were renowned psychologists. Both
men and their colleagues established laboratory studies of
chimpanzees focused specifically on learning about the
intellectual abilities of chimpanzees, particularly
This typically involved basic, practical tests on laboratory
chimpanzees, which required a fairly high intellectual capacity
(such as how to solve the problem of acquiring an out-of-reach
banana). Notably, Yerkes also made extensive observations of
chimpanzees in the wild which added tremendously to the
scientific understanding of chimpanzees and their behaviour.
Yerkes studied chimpanzees until World War II, while Köhler
concluded five years of study and published his famous
Mentality of Apes in 1925 (which is coincidentally when
Yerkes began his analyses), eventually concluding that
"chimpanzees manifest intelligent behaviour of the general kind
familiar in human beings ... a type of behaviour which counts as
specifically human" (1925).
The August 2008 issue of the American Journal of
Primatology reported results of a year-long study of
chimpanzees in Tanzania’s Mahale Mountains National Park which
produced evidence that chimpanzees are becoming sick from viral
infectious diseases they have likely contracted from humans.
Molecular, microscopic and epidemiological investigations
demonstrated that the chimpanzees living at Mahale Mountains
National Park have been suffering from a respiratory disease
that is likely caused by a variant of a human paramyxovirus.
|Rescued chimpanzee - Cameroon
As of November 2007, there were 1,300 chimpanzees 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.
Most of the labs either conduct or make the chimps available for
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: Yerkes National
Primate Research Laboratory at Emory University in Atlanta,
Georgia, and the Southwest National Primate Center in San
Five hundred chimps have been retired from laboratory use in the
U.S. and live in 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
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, who 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 used in research into alcohol use, oral
contraceptives, ageing, and cognitive studies.
With the publication of the chimpanzee genome, there are
reportedly plans to increase the use of chimps in labs, 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 (NIH) in 1996, because too many chimps had
been bred for HIV research, and it has been extended annually
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 that, given chimpanzees' sense of self, tool use, and
genetic similarity to human beings, studies using chimps should
follow the ethical guidelines that are used for human subjects
unable to give consent.
Also, a recent study suggests that chimpanzees which are
retired from labs exhibit a form of posttraumatic stress
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
An increasing number of governments are enacting 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.
Chimpanzees have been commonly stereotyped in popular
culture, where they are most often cast in standardized roles
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
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
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
Animal rights group, PETA, has urged advertisers against the use
of chimpanzees in television and commercials, citing animal
When chimpanzees appear in other TV shows, they generally do
so as comic relief sidekicks to humans. In that role, for
instance, J. Fred Muggs appeared with Today Show host
Dave Garroway in the 1950s, Judy on Daktari in the 1960s
or 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.
Portrayals in science fiction
The rare depictions of chimpanzees as individuals rather than
stock characters, and as central rather than incidental to the
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, set
in the near future, portrays a revolt of enslaved apes led by
the only talking chimpanzee, Caesar, against their human
Another short story "The Pope of the Chimps" by Robert
Silverberg, set in the present day, shows the development of the
first signs of religiosity in a group of chimpanzees, much to
the surprise of the humans observing them. David Brin's Uplift
novels present a future in which humans have "uplifted"
chimpanzees (and certain other species) with human-level
|Those are beautiful pictures of
Chimps. I enjoyed the video very much. Thank you for everything you
do to help the Chimpanzee. Lynn
|We are fortunate to share the world with such
interesting creatures. I am against exploiting the Chimpanzees, they
never should of been removed from Africa, that is their home. I am
hoping that the USA will stop using them in research.
|i hate chimpanzee abuse so sad and they
have no say in this at all they have no right to be treated like