Changes

A full grown adult male chimpanzee can weigh from 35 to 70 kilograms (75-155 pounds) and stand 0.9-1.2 meters (3–4 feet) tall, while females usually weigh 26–50 kg (57-110 pounds) and stand 0.66–1 meters (2.0-3.5 feet) tall.

A full grown adult male chimpanzee can weigh from 35 to 70 kilograms (75-155 pounds) and stand 0.9-1.2 meters (3–4 feet) tall, while females usually weigh 26–50 kg (57-110 pounds) and stand 0.66–1 meters (2.0-3.5 feet) tall.

Chimpanzees have both opposable big toes and opposable thumbs. Most primates have nine wrist bones. Humans, chimps and gorillas have eight; two have fused, stabilising the wrist for knuckle-walking.

Chimpanzees have both opposable big toes and opposable thumbs. Most primates have nine wrist bones. Humans, chimps, and gorillas have eight; two have fused, stabilizing the wrist for knuckle-walking.

==Lifespan==

==Lifespan==

Chimpanzees rarely live past the age of 50 in the wild, but have been known to reach the age of 60 in captivity, and ''Tarzan'' star Cheeta is still alive (as of 2006) at the age of 74.

Chimpanzees rarely live past the age of 50 in the wild but have been known to reach the age of 60 in captivity. ''Tarzan'' star Cheeta is still alive (as of 2006) at the age of 74.

==Social organization==

==Social organization==

Chimps travel in small, frequently-changing groups. Larger groups gather around food or an attractive female. Different groups use different tools. Some "fish" for termites with twigs; others crack nuts with rocks or sharpen spears with their teeth to hunt bush-babies.<ref>http://news.bbc.co.uk/1/hi/sci/tech/6387611.stm</ref>

Chimps travel in small, frequently changing groups. Larger groups gather around food or an attractive female. Different groups use different tools. Some "fish" for termites with twigs; others crack nuts with rocks or sharpen spears with their teeth to hunt bush-babies.<ref>http://news.bbc.co.uk/1/hi/sci/tech/6387611.stm</ref>

Males co-operate in hunting and share meat afterwards. Although chimps like meat, it forms only 2% of their diet. Bonobos rarely eat it, and both species prefer fruit. Hunts mainly happen during food shortages or for mating displays.

Males co-operate in hunting and share meat afterward. Although chimps like meat, it forms only 2% of their diet. Bonobos rarely eat it, and both species prefer fruit. Hunts mainly happen during food shortages or for mating displays.

Angry chimps stand upright, swagger, charge, scream and throw things. Grins usually show fear. Social grooming helps maintain calm and friendly relations. Males from neighboring communities are aggressive with each other.

Angry chimps stand upright, swagger, charge, scream, and throw things. Grins usually show fear. Social grooming helps maintain calm and friendly relations. Males from neighboring communities are aggressive with each other.

=== Beta male chimpanzee behavior ===

=== Beta male chimpanzee behavior ===

==Chimp intelligence==

==Chimp intelligence==

Chimps can recognise themselves in a mirror, vocalise and show similar nonverbal communication patterns to humans. Young chimps laugh when playful or being tickled. They appear to express emotions. Individuals identify themselves with distinctive sounds. Chimpanzees don't have the physiology for speech, but can learn some human language – Washoe learned over 800 ASL signs in the 1960s – though without [[grammar]], syntax or words with variable meaning. Some people compare the usage of ASL by chimpanzees to a [[parrot]] speaking due to both animals not really understanding what they are communicating.

Chimps can recognize themselves in a mirror, vocalize, and show similar nonverbal communication patterns to humans. Young chimps laugh when playful or being tickled. They appear to express emotions. Individuals identify themselves with distinctive sounds. Chimpanzees don't have the physiology for speech, but can learn some human language – Washoe learned over 800 ASL signs in the 1960s – though without [[grammar]], syntax or words with variable meaning. Some people compare the usage of ASL by chimpanzees to a [[parrot]] speaking due to both animals not really understanding what they are communicating.

Chimp and human brain and CNS anatomy, blood composition and immune response are similar. Many behaviors are similar. However, chimps don't share history, make long-term plans, or engage in group discussions. The brightest chimp is intellectually duller than a normal human. A form of neuropsin, a protein with a role in learning and memory, believed by evolutionists to have originated less than 5 million years ago, is expressed only in humans.

Chimp and human brain and CNS anatomy, blood composition, and immune response are similar. Many behaviors are identical. However, chimps don't share history, make long-term plans, or engage in group discussions. The brightest chimp is intellectually duller than an average human. A form of neuropsin, a protein with a role in learning and memory, believed by evolutionists to have originated less than 5 million years ago, is expressed only in humans.

In tests performed by scientists, chimpanzees were shown to not understand that a human needs to be facing the chimpanzees in order to see them. These results indicate that the intellectual chasm between chimpanzees and humans is larger than previously believed.

In tests performed by scientists, chimpanzees were shown to not understand that humans need to face the chimpanzees in order to see them. These results indicate that the intellectual chasm between chimpanzees and humans is larger than previously believed.

==Chimps and HIV==

==Chimps and HIV==

HIV may have originated in chimpanzees when they ate monkeys infected with a simian virus, which mutated. This increases the urgency of preserving chimps in their habitat, although commercial logging, bushmeat and the illegal pet trade have put chimps at risk of extinction.<ref>http://www.newscientist.com/channel/health/hiv/dn1991</ref>

HIV may have originated in chimpanzees when they ate monkeys infected with a mutated simian virus. This increases the urgency of preserving chimps in their habitat, although commercial logging, bushmeat and the illegal pet trade have put chimps at risk of extinction.<ref>http://www.newscientist.com/channel/health/hiv/dn1991</ref>

==Are chimpanzees related to humans?==

==Are chimpanzees related to humans?==

The genus ''Pan'' is now considered to be part of the subfamily [[Hominidae]] to which [[human]]s also belong. [[Theory of evolution|Evolutionary]] [[Biology|biologists]] believe that the two species of chimpanzees are the closest living [[evolution]]ary relatives to humans. It is thought that humans shared a common ancestor with chimpanzees and gorillas as recently as [[Pliocene|four]] to [[Miocene|seven million years ago]]. Groundbreaking research by [[Mary-Claire King]] in 1973 found 99% identical [[DNA]] between human beings and chimpanzees,<ref>Mary-Claire King, ''Protein polymorphisms in chimpanzee and human evolution'', Doctoral dissertation, University of California, Berkeley (1973).</ref> although research since has modified that finding to about 94% commonality,<ref name=ns>{{cite web | url = http://www.sciam.com/article.cfm?chanID=sa003&articleID=9D0DAC2B-E7F2-99DF-3AA795436FEF8039 |date = 2006-12-19 | title = Humans and Chimps: Close But Not That Close | publisher = Scientific American | accessdate = 2006-12-20}}</ref> with at least some of the difference occurring in "junk" DNA. It has even been proposed that ''troglodytes'' and ''paniscus'' belong with ''sapiens'' in the genus ''[[Homo (genus)|Homo]]'', rather than in ''Pan''. One argument 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 and chimpanzees. Indeed, cladistic taxonomy, based on both genetic difference and date of likely divergence, is very clear in placing both extant species of ''Pan'' in the genus ''Homo'', mainly because the genus ''Homo'' takes precedence on account of being coined first. It is very important, however, to consider where the differences in the genome appear.<ref>https://www.sciencedaily.com/releases/2006/12/061219201931.htm</ref>

The genus ''Pan'' is now considered to be part of the subfamily [[Hominidae]] to which [[human]]s also belong. [[Theory of evolution|Evolutionary]] [[Biology|biologists]] believe that the two species of chimpanzees are the closest living [[evolution]]ary relatives to humans. It is thought that humans shared a common ancestor with chimpanzees and gorillas as recently as [[Pliocene|four]] to [[Miocene|seven million years ago]]. Groundbreaking research by [[Mary-Claire King]] in 1973 found 99% identical [[DNA]] between human beings and chimpanzees,<ref>Mary-Claire King, ''Protein polymorphisms in chimpanzee and human evolution'', Doctoral dissertation, University of California, Berkeley (1973).</ref> although research since has modified that finding to about 94% commonality,<ref name=ns>{{cite web | url = http://www.sciam.com/article.cfm?chanID=sa003&articleID=9D0DAC2B-E7F2-99DF-3AA795436FEF8039 |date = 2006-12-19 | title = Humans and Chimps: Close But Not That Close | publisher = Scientific American | accessdate = 2006-12-20}}</ref> with at least some of the difference occurring in "junk" DNA. It has even been proposed that ''troglodytes'' and ''paniscus'' belong with ''sapiens'' in the genus ''[[Homo (genus)|Homo]]'', rather than in ''Pan''. One argument for this is that other species have been reclassified to belong to the same genus based on less genetic similarity than that between humans and chimpanzees. Indeed, cladistic taxonomy, based on both genetic difference and date of likely divergence, is very clear in placing both extant species of ''Pan'' in the genus ''Homo'', mainly because the genus ''Homo'' takes precedence on account of being coined first. It is very important, however, to consider where the differences in the genome appear.<ref>https://www.sciencedaily.com/releases/2006/12/061219201931.htm</ref>

Most biologists hold the view that chimpanzees and humans share a close common ancestor due to molecular, morphological, physiological, geographical and behavioral similarities. Although in some cases [[convergent evolution]] makes for such similarities in distantly related organisms the similarities between humans and chimps include neutral genetic markers that could not be subject to convergent evolution.<ref>A. Hobolth et al. (2007) Genomic relationships and speciation times of human, chimpanzee, and gorilla inferred from a coalescent hidden Markov model. ''PLOS Genetics'' '''23:'''e7</ref>

Most biologists hold the view that chimpanzees and humans share a close common ancestor due to molecular, morphological, physiological, geographical and behavioral similarities. Although in some cases [[convergent evolution]] makes for such similarities in distantly related organisms the similarities between humans and chimps include neutral genetic markers that could not be subject to convergent evolution.<ref>A. Hobolth et al. (2007) Genomic relationships and speciation times of human, chimpanzee, and gorilla inferred from a coalescent hidden Markov model. ''PLOS Genetics'' '''23:'''e7</ref>

A study published by Clark and Nielsen of [[Cornell University]] in the December 2003 issue of the journal ''[[Science (journal)|Science]]'' highlights differences related to one of humankind's defining qualities &ndash; the ability to understand [[language]] and to communicate through speech. These macro-phenotypic differences, however, may owe less to physiology than might be assumed given that ''Homo sapiens'' developed modern cultural features long after the modern physiological features were in place and indeed competed averagely against other species of ''Homo'' with regard to tools, etc. for many millennia. Differences also exist in the genes for smell, in genes that regulate the metabolism of amino acids and in genes that may affect the ability to digest various proteins.  

A study published by Clark and Nielsen of [[Cornell University]] in the December 2003 issue of the journal ''[[Science (journal)|Science]]'' highlights differences related to one of humankind's defining qualities &ndash; the ability to understand [[language]] and to communicate through speech. These macro-phenotypic differences, however, may owe less to physiology than might be assumed given that ''Homo sapiens'' developed modern cultural features long after the modern physiological features were in place and indeed competed averagely against other species of ''Homo'' concerning tools, etc., for many millennia. Differences also exist in the genes for smell, in genes that regulate the metabolism of amino acids and in genes that may affect the ability to digest various proteins.  

===Fossils===

===Fossils===

[[Category:Hominid]]

[[Category:Hominid]]