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'''Primates''' are an order of [[Mammal|mammals]] which in living diversity include, [[prosimians]] (galagos, lorises, lemurs and tarsiers), [[platyrrhines]] (New World monkeys), cercopithecids (Old World monkeys) and hominoids  (apes and humans). They have their origins in some type of an [[Insectivore|insectivorous]] mammal that lived in the late [[Cretaceous]]<ref name="Fleagle">{{cite book|title=Primate Adaptation and Evolution|accessdate=|author=J. Fleagle|authorlink= |coauthors= |date=1998 |format= |work= |publisher=Academic Press: New York|pages= |language= |archiveurl= |archivedate= |quote= }}</ref><ref name="Szalay">{{cite book |title=Evolutionary History of the Primates|accessdate=|author=F. Szalay and E. Delson|authorlink= |coauthors= |date=2001 |format= |work= |publisher=Academic Press, New York|pages= |language= |archiveurl= |archivedate= |quote= }}</ref>.
{{subpages}}
{{Taxobox
| color = pink
| name = Primates
| fossil_range = [[Paleocene]] - Recent
| image = baboon1.jpg
| image_width = 200px
| image_caption = An "Old World" monkey - ''Papio anubis''.  This male baboon at Ngorongoro Crater, Tanzania is holding an infant.
| regnum = [[Animal]]ia
| phylum = [[Chordate|Chordata]]
| classis = [[Mammal]]ia
| infraclassis = [[Eutheria]]
| superordo = [[Euarchontoglires]]
| ordo = '''Primates'''
| ordo_authority = [[Carolus Linnaeus|Linnaeus]], 1758
}}
 
'''Primates''' are an order of [[Mammal|mammals]] which in living diversity include, [[Prosimian|prosimians]] (galagos, lorises, [[Lemur|lemurs]] and tarsiers), [[Monkey|platyrrhines]] (New World [[Monkey|monkeys]]), [[Monkey|cercopithecids]] (Old World monkeys) and hominoids  ([[Ape|apes]] and humans). They have their origins in some type of an [[Insectivore|insectivorous]] mammal that lived in the late [[Cretaceous]]<ref name="Fleagle">{{cite book|title=Primate Adaptation and Evolution|accessdate=|author=J. Fleagle|authorlink= |coauthors= |date=1998 |format= |work= |publisher=Academic Press: New York|pages= |language= |archiveurl= |archivedate= |quote= }}</ref><ref name="Szalay">{{cite book |title=Evolutionary History of the Primates|accessdate=|author=F. Szalay and E. Delson|authorlink= |coauthors= |date=2001 |format= |work= |publisher=Academic Press, New York|pages= |language= |archiveurl= |archivedate= |quote= }}</ref>.
 
==Description==
==Description==


All primates have a [[primitive]] [[Teeth|dental]] plan, five fingers, nails instead of claws, a thumb and a generalized body plan. All primates share a similar eye orbit morphology and have a [[post-orbital bar]]<ref name="Szalay"/>. All primates have forward facing eyes<ref name="Eyes">{{cite web |url=http://news.nationalgeographic.com/news/2006/08/060810-snake-evolve.html|title=Snake Threat May Have Spurred Evolution of Primate Eyes|accessdate=2007-08-10|author=S. Lovgren|authorlink= |coauthors= |date=2006 |format= |work= |publisher=National Geographic|pages= |language= |archiveurl= |archivedate= |quote= }}</ref>.
All primates have a [[primitive]] [[Teeth|dental]] plan, five fingers, nails instead of claws, a thumb and a generalized body plan. All primates share a similar eye orbit morphology and have a [[post-orbital bar]]<ref name="Szalay"/>. All primates have forward facing eyes<ref name="Eyes">{{cite web |url=http://news.nationalgeographic.com/news/2006/08/060810-snake-evolve.html|title=Snake Threat May Have Spurred Evolution of Primate Eyes|accessdate=2007-08-10|author=S. Lovgren|authorlink= |coauthors= |date=2006 |format= |work= |publisher=National Geographic|pages= |language= |archiveurl= |archivedate= |quote= }}</ref>.
==Geographical distribution==
Due to the recent spread of humans in the last 12,000 years, primates are a probably the most geographically distributed mammal, occupying every [[continent]].  Non-human primates are [[indigenous]] to South and [[Central America]], Africa, Asia and the the islands of [[Indonesia]].


==Prosimians==
==Prosimians==


Prosimian primates are the most primitive of living primates and share many morphological characteristics with other mammals such as [[Tree shrew|tree shrews]] and [[bats]]<ref name="Szalay"/>. The greatest diversity of prosimian primates is found on the island of [[Madagascar]]<ref name="Madagascar">{{cite web |url=http://news.mongabay.com/2005/0709-wildmadagascar.html|title=Madagascar lemurs descended from single primate ancestor|accessdate=2007-08-10|author=Wild Madagascar|authorlink= |coauthors= |date=2005 |format= |work= |publisher=Wildmadagascar.com|pages= |language= |archiveurl= |archivedate= |quote= }}</ref>, but all species of living prosimian species are found only in the Old World.
[[Prosimian]] primates are the most primitive of living primates and share many morphological characteristics with other mammals such as [[Tree shrew|tree shrews]] and [[bats]]<ref name="Szalay"/>. The greatest diversity of prosimian primates is found on the island of [[Madagascar]]<ref name="Madagascar">{{cite web |url=http://news.mongabay.com/2005/0709-wildmadagascar.html|title=Madagascar lemurs descended from single primate ancestor|accessdate=2007-08-10|author=Wild Madagascar|authorlink= |coauthors= |date=2005 |format= |work= |publisher=Wildmadagascar.com|pages= |language= |archiveurl= |archivedate= |quote= }}</ref>, but all species of living prosimian species are found only in the [[Old World]].
 
===Lemurs===
[[Lemur]]s exist only on the island of [[Madagascar]] and the neighbouring islands of the [[Comores]].  They are among the most primitive of primates.  They have moist noses and reflective eyes.  They range in body size from the 30 gram Pygmy lemur to the 10kg [[Indri|Indri]]. Due to their geographically restricted range and destruction of habitat by humans, all lemur species are endangered<ref name="Fleagle"/><ref name="Szalay"/>.
 
===Lorises===
 
[[Lorise]]s are arboreal prosimian primates who live in [[India]] and southeast [[Asia]].  They live in tropical areas, typically high in the canopy and rarely come to the ground<ref name="Fleagle"/><ref name="Szalay"/>.  They are known to be very slow moving.
 
===Galagos===
 
[[Galago]]s, also known as bushbabies, are small, arboreal nocturnal primates with large [[eye]]s. They are native to [[Africa]]. Bushbabies are extremely adept leapers<ref name="Fleagle"/>.
 
===Tarsiers===
 
[[Tarsier]]s are a nocturnal, arboreal primate restricted to several islands in southeast Asia. They are primarily [[insectivores|insectiverous]] and are agile leapers. Unlike most nocturnal primates, they have non-reflective eyes.


==Monkeys==  
==Monkeys==  
There are two basic types of monkeys - platyrrhines and catarrhines. [[South America|South American]] monkeys are known as platyrrhines and differ considerably from the catarrhines monkeys, having evolved largely in isolation<ref name="Fleagle"/><ref name="Szalay"/>.
There are two basic types of monkeys - platyrrhines and catarrhines. [[South America|South American]] monkeys are known as platyrrhines and differ considerably from the catarrhines monkeys, having evolved largely in isolation<ref name="Fleagle"/><ref name="Szalay"/>.    


===Platyrrhine monkeys===
===Platyrrhine monkeys===
.[[Image:baboon1.jpg|thumb|right|150px|An "Old World" monkey - ''Papio anubis''.  This male baboon at Ngorongoro Crater, Tanzania is holding an infant.]]   
 
The name platyrrhine derives from the broad, flat shape of their external [[nostrils]].  All platyrrhines are small, the largest is only around 10kg<ref name="Fleagle"/>.  They also exhibit many [[primitive]] dental and skeletal features including having three [[pre-molars]]<ref name="Szalay"/>.   
The name platyrrhine derives from the broad, flat shape of their external [[nostrils]].  All platyrrhines are small, the largest is only around 10kg<ref name="Fleagle"/>.  They also exhibit many [[primitive]] dental and skeletal features including having three [[pre-molars]]<ref name="Szalay"/>.   


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===Catarrhine monkeys===
===Catarrhine monkeys===


Catarrhines monkeys are "Old World Monkeys" and all fall under the Superfamily Cercopithecidae<ref name="Szalay"/>.  They have narrow noses, eight pre-molars and none have prehensile tails<ref name="Fleagle"/>. There are two Subfamilies within the Superfamily - Cercopithecinae and Colobinae<ref name="Szalay"/>.  There are approximatly sixty species of cercopithicus monkey and about forty species of Colobus monkey.
Catarrhines monkeys are "Old World Monkeys" and all fall under the Superfamily Cercopithecidae<ref name="Szalay"/>.  They have narrow noses, eight pre-molars and none have prehensile tails<ref name="Fleagle"/>. There are two Subfamilies within the Superfamily - Cercopithecinae and Colobinae<ref name="Szalay"/>.  There are approximately sixty species of cercopithicus monkey and about forty species of Colobus monkey.


==Apes==
==Apes and humans==


The living apes are generally considered to be primates who are tailess, of relatively large body size and all live in the old world. Typically included in the grouping "apes" are gibbons and siamangs from southeast Asia, Orangutans from borneo and Sumatra, Mountain and Lowland Gorillas, Chimpanzees and Bonobos and humans. Under the modern genetic classification scheme (see ''[[Hominini]]'' for more on this), apes are in the superfamily ''Hominoidea''.  Underneath this hominoid umbrella falls orang-utans, gorillas, chimps and humans in the Family ''Hominidae''. In recognition of their genetic divergence some 11-13 million years ago, the orangutans are placed in the sub-family ''Ponginae'' and the African apes, including humans, are lumped together in the Subfamily Homininae. The bipedal apes, namely all of the fossil species as well as living humans, fall into the Tribe ''Hominini''<ref name="Berger1">{{cite web |url=http://http://news.nationalgeographic.com/news/2001/12/1204_hominin_id.html|title=Is it time to revise the system of scientific naming|accessdate=2007-08-10|author=L.R. Berger|authorlink= |coauthors= |date=2001 |format= |work= |publisher=National Geographic|pages= |language= |archiveurl= |archivedate= |quote= }}</ref>.  Some evolutionary biologists include humans and chimpanzees within the same [[genus]], the genus ''Homo''.  The more traditional [[Carl Linnaeus|Linnaean]] clasification of primates may be found in the "List of Primate Species" at the end of this article.
The living apes are generally considered to be primates who are tailess, of relatively large body size and all live in the old world. Typically included in the grouping "apes" are gibbons and siamangs from southeast Asia, Orangutans from Borneo and [[Sumatra]], Mountain and Lowland Gorillas, Chimpanzees and Bonobos and humans. Under the modern genetic classification scheme (see ''[[Hominini]]'' for more on this), apes are in the superfamily ''Hominoidea''.  Underneath this hominoid umbrella falls orang-utans, gorillas, chimps and humans in the Family ''Hominidae''. In recognition of their genetic divergence some 11-13 million years ago, the orangutans are placed in the sub-family ''Ponginae'' and the African apes, including humans, are lumped together in the Subfamily Homininae. The bipedal apes, namely all of the fossil species as well as living humans, fall into the Tribe ''Hominini''<ref name="Berger1">{{cite web |url=http://news.nationalgeographic.com/news/2001/12/1204_hominin_id.html|title=Is it time to revise the system of scientific naming|accessdate=2007-08-10|author=L.R. Berger|authorlink= |coauthors= |date=2001 |format= |work= |publisher=National Geographic|pages= |language= |archiveurl= |archivedate= |quote= }}</ref>.  Some evolutionary biologists include humans and chimpanzees within the same [[genus]], the genus ''Homo''.  The more traditional [[Carl Linnaeus|Linnaean]] clasification of primates may be found in the "List of Primate Species" at the end of this article.


==Primate evolution==
==Primate evolution==
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The earliest possible primate discovered so far comes from North America and is about 60 million years old<ref name="Fleagle"/><ref name="Szalay"/>.  Named ''Purgatorius'', this tiny insectivore is only loosely morphologically allied with later primates<ref name="Szalay"/>.  There are possible older ''Purgatorius'' specimens going back into the latest Cretaceous, but most are from dubious context.  It is only in the late [[Paleocene]] (about 55 million years ago) that we see more numerous remains of primate-like animals appearing in the fossil record<ref name="Fleagle"/><ref name="Szalay"/>.  
The earliest possible primate discovered so far comes from North America and is about 60 million years old<ref name="Fleagle"/><ref name="Szalay"/>.  Named ''Purgatorius'', this tiny insectivore is only loosely morphologically allied with later primates<ref name="Szalay"/>.  There are possible older ''Purgatorius'' specimens going back into the latest Cretaceous, but most are from dubious context.  It is only in the late [[Paleocene]] (about 55 million years ago) that we see more numerous remains of primate-like animals appearing in the fossil record<ref name="Fleagle"/><ref name="Szalay"/>.  


Known as the [[Plesiadapiform|Plesiadapiforms]] these near-primates appear to have evolved in [[North America]] and [[Europe]]<ref name="Szalay"/>.  The Plesiadapiforms radiated into many different niches, but in the early Eocene (about  45 to 50 million years ago), it seems that the rise of rodents caused a rapid decline in the number and diversity of Plesiadapiforms<ref name="Szalay"/>. But Plesiadapiforms are probably not the ancestors of living primates, as they possessed too many specializations to have given rise to the first Prosimian primates that would appear a few million years later<ref name="Szalay"/>.  So at this time, the only primate-like mammal that is a firm candidate as ancestor of all higher primates is the tiny ''Purgatorius''.  
Known as the [[Plesiadapiform|Plesiadapiforms]] these near-primates appear to have evolved in [[North America]] and [[Europe]]<ref name="Szalay"/>.  The Plesiadapiforms radiated into many different niches, but in the early Eocene (about  45 to 50 million years ago), it seems that the rise of rodents caused a rapid decline in the number and diversity of Plesiadapiforms<ref name="Szalay"/>. But Plesiadapiforms are probably not the ancestors of living primates, as they possessed too many specializations to have given rise to the first Prosimian primates that would appear a few million years later<ref name="Szalay"/>.  So at this time, the only primate-like mammal that is a firm candidate as ancestor of all higher primates is the tiny ''Purgatorius''.  


The first true, prosimian primates appear, and literally explode in diversity, in the early [[Eocene Epoch]] (between 54 and 38 million years ago)<ref name="Fleagle"/>.  Eocene aged Prosimian primates are commonly found in North America and Europe and more rarely in Asia and Africa.  No early primates have ever been found in South America or Antarctica as the former was an island continent, while we have as of yet found fossil deposits of this age in the latter<ref name="Szalay"/>.  In these earliest primates the bony ring around the orbit was complete like in modern primates, nails replaced claws and larger brains  were evolved.  These early Eocene primates were clearly true primates and took two distinct forms: lemur-like adapids and galago- (bushbaby) like [[omomyids]]<ref name="Fleagle"/>.  Although the living forms are different species, these animals descendants can clearly be seen in the lemurs of Madagascar and the galagos, lorises and tarsiers of [[Africa]] and [[Asia]].   
The first true prosimian primates appeared, and exploded in diversity, in the early [[Eocene Epoch]] (between 54 and 38 million years ago)<ref name="Fleagle"/>.  Eocene aged Prosimian primates are commonly found in North America and Europe and more rarely in Asia and Africa.  No early primates have ever been found in South America or Antarctica as the former was an island continent, while we have as of yet found fossil deposits of this age in the latter<ref name="Szalay"/>.  In these earliest primates the bony ring around the orbit was complete like in modern primates, nails replaced claws and larger brains  were evolved.  These early Eocene primates were clearly true primates and took two distinct forms: lemur-like adapids and galago- (bushbaby) like [[omomyids]]<ref name="Fleagle"/>.  Although the living forms are different species, these animals descendants can clearly be seen in the lemurs of Madagascar and the galagos, lorises and tarsiers of [[Africa]] and [[Asia]].   


As the Eocene drew to a close and the Oligocene epoch began about 37 million years ago, the continents were approaching their modern form and position, with the exception of there being no land bridge between South America and North America<ref name="Fleagle"/><ref name="Szalay"/>.  The world was however, in a state of geographical transition.  India was colliding with the continent of Asia, lifting the great Himalayas<ref name="Nova">>{{cite web |url=http://www.pbs.org/wgbh/nova/everest/earth/birth.html|title=Birth of the Himilaya|accessdate=2007-08-11|author=R. Bilham|authorlink= |coauthors= |date=2000 |format= |work= |publisher=PBS|pages= |language= |archiveurl= |archivedate= |quote= }}</ref>.  South America and Australia had pulled away from Antarctica and formed independent island continents.  Deep water currents could thus circulate around Antarctica, bringing cold waters northward and subsequently cooling the oceans of the world.  At the same time, the rise of the Himalayas blocked the  northward curve of the jet stream, changing the climate south of this great mountain range<ref name="Nova"/>.   
As the Eocene drew to a close and the Oligocene epoch began about 37 million years ago, the continents were approaching their modern form and position, with the exception that there was no land bridge between South America and North America<ref name="Fleagle"/><ref name="Szalay"/>.  The world was however, in a state of geographical transition.  India was colliding with the continent of Asia, lifting the great Himalayas<ref name="Nova">>{{cite web |url=http://www.pbs.org/wgbh/nova/everest/earth/birth.html|title=Birth of the Himilaya|accessdate=2007-08-11|author=R. Bilham|authorlink= |coauthors= |date=2000 |format= |work= |publisher=PBS|pages= |language= |archiveurl= |archivedate= |quote= }}</ref>.  South America and Australia had pulled away from Antarctica and formed independent island continents.  Deep water currents could thus circulate around Antarctica, bringing cold waters northward and subsequently cooling the oceans of the world.  At the same time, the rise of the Himalayas blocked the  northward curve of the jet stream, changing the climate south of this great mountain range<ref name="Nova"/>.   


Primates in Europe suddenly go extinct while in North America their fossils become increasingly rare and there is a general decline in mammalian diversity<ref name="Szalay"/>.  Up until recently the global climatic changes of the early Oligocene have been blamed almost wholly on the mammalian extinctions that occurred at this time, but in November of 2001, scientists from the United States Geological Service announced that what was previously thought to be a relatively small extraterrestrial impact in the Chesapeake Bay area was in fact quite large (around 137 kilometers in diameter), and struck at approximately 35 million years ago<ref>{{cite web |url=http://www.usgs.gov/features/bolide.html|title=The Chesapeake Meteorite: Message from the Past|accessdate=2007-08-11|author=USGS|authorlink= |coauthors= |date=2001 |format= |work= |publisher=|pages= |language= |archiveurl= |archivedate= |quote= }}</ref>, right at the point of extinction of many of the North American primates and at a point of general loss of mammalian diversity<ref>{{cite book |title=Primate fact sheet|accessdate=2007-08-11|author=Primata|authorlink= |coauthors= |date=2007 |format= |work= |publisher=|pages= |language= |archiveurl= |archivedate= |quote= }}</ref>.
Primates in Europe suddenly go extinct while in North America their fossils become increasingly rare and there is a general decline in mammalian diversity<ref name="Szalay"/>.  Until recently, the global climatic changes of the early Oligocene have been blamed almost wholly on the mammalian extinctions that occurred at this time, but in November of 2001, scientists from the United States Geological Service announced that what was previously thought to be a relatively small extraterrestrial impact in the Chesapeake Bay area was in fact quite large (around 137 kilometers in diameter), and struck at approximately 35 million years ago<ref>{{cite web |url=http://www.usgs.gov/features/bolide.html|title=The Chesapeake Meteorite: Message from the Past|accessdate=2007-08-11|author=USGS|authorlink= |coauthors= |date=2001 |format= |work= |publisher=|pages= |language= |archiveurl= |archivedate= |quote= }}</ref>, right at the point of extinction of many of the North American primates and at a point of general loss of mammalian diversity<ref>{{cite book |title=Primate fact sheet|accessdate=2007-08-11|author=Primata|authorlink= |coauthors= |date=2007 |format= |work= |publisher=|pages= |language= |archiveurl= |archivedate= |quote= }}</ref>.


==A primate puzzle==
==A primate puzzle==


Prior to about 30 million years ago there are no primates or even primate-like animals in South America<ref name="Fleagle"/><ref name="Szalay"/>.  Around 25 to 30 million years ago a wide variety of new forms of mammal suddenly appear in South America but it is unkown where they come from<ref name="Szalay"/>. Among the new forms are rare fossil primates which look very much like existing Platyrrhines<ref name="Szalay"/>. As the only major difference in continental position between that of today and then was that no land bridge existed between North and South America, any introduction of primates into South America would require some form of open water crossing, possibly rafting on large fallen tree trunks or large mats of vegetation<ref name="Ciochon">{{cite book |title=Evolutionary Biology of the New World Monkeys and Continental Drift |accessdate=|author=R.L. Ciochon and A.B. Chiarelli| authorlink= |coauthors= |date=1981 |format= |work= |publisher=Plenum Pub Corp |pages= 528p|language= |archiveurl= |archivedate= |quote= }}</ref>.  Because of relatively shallow water in the South Atlantic during lower sea level periods, there were almost certainly many islands exposed between Africa and South America, effectively bringing the two continents much closer together and making potential rafting hops shorter.  In fact, most [[Geophysics|geophysicists]] suggest that at the time the open water distance between North America and South America was probably greater than that between the latter and Africa<ref name="Ciochon"/>.
Prior to about 30 million years ago there are no primates or even primate-like animals in South America<ref name="Fleagle"/><ref name="Szalay"/>.  Around 25 to 30 million years ago a wide variety of new forms of mammal suddenly appear in South America but it is unknown where they come from<ref name="Szalay"/>. Among the new forms are rare fossil primates which look very much like existing Platyrrhines<ref name="Szalay"/>. As the only major difference in continental position between that of today and then was that no land bridge existed between North and South America, any introduction of primates into South America would require some form of open water crossing, possibly rafting on large fallen tree trunks or large mats of vegetation<ref name="Ciochon">{{cite book |title=Evolutionary Biology of the New World Monkeys and Continental Drift |accessdate=|author=R.L. Ciochon and A.B. Chiarelli| authorlink= |coauthors= |date=1981 |format= |work= |publisher=Plenum Pub Corp |pages= 528p|language= |archiveurl= |archivedate= |quote= }}</ref>.  Because of relatively shallow water in the South Atlantic during lower sea level periods, there were almost certainly many islands exposed between Africa and South America, effectively bringing the two continents much closer together and making potential rafting hops shorter.  In fact, most [[Geophysics|geophysicists]] suggest that at the time the open water distance between North America and South America was probably greater than that between the latter and Africa<ref name="Ciochon"/>.


Predications of current direction also tentatively support a West to East crossing rather than a North to South rafting event<ref name="Ciochon"/>. The fossil record also supports an “Out of Africa theory by raft” for the origin of Platyrrhines.  At this time, there are simply no known primates advanced enough in North America to be suitable ancestral candidates of the early Platyrrhines<ref name="Szalay"/><ref name="Ciochon"/>, but Africa has a host of possible ancestral Platyrrhine forms. Further tantalizing evidence of an African connection is the fact that the closest living relatives of South American [[Rodent|rodents]] are the African Hystricids, more commonly known as porcupines<ref name="Ciochon"/><ref name="Szalay"/>.   
Predications of current direction also tentatively support a West to East crossing rather than a North to South rafting event<ref name="Ciochon"/>. The fossil record also supports an “Out of Africa theory by raft” for the origin of Platyrrhines.  At this time, there are simply no known primates advanced enough in North America to be suitable ancestral candidates of the early Platyrrhines<ref name="Szalay"/><ref name="Ciochon"/>, but Africa has a host of possible ancestral Platyrrhine forms. Further tantalizing evidence of an African connection is the fact that the closest living relatives of South American [[Rodent|rodents]] are the African Hystricids, more commonly known as porcupines<ref name="Ciochon"/><ref name="Szalay"/>.   


Another possible source for Platyrrhine origins would be Antarctica, but we know nothing about the later fossil record, if it exists at all, of Antarctica at this time<ref name="Ciochon"><ref name="Szalay"/>. The same may be said about Asia, where there is presently little or no evidence for Platyrrhine origins<ref name="Ciochon"><ref name="Szalay"/>.   
Another possible source for Platyrrhine origins would be Antarctica, but we know nothing about the later fossil record, if it exists at all, of Antarctica at this time<ref name="Ciochon"/><ref name="Szalay"/>. The same may be said about Asia, where there is presently little or no evidence for Platyrrhine origins<ref name="Ciochon"/><ref name="Szalay"/>.   


==Living Primate Species==<ref name="Fleagle"/><ref>{{cite web |url=http://www.theprimata.com/factsheets.html|title=Primate fact sheet|accessdate=2007-08-11|author=Primata|authorlink= |coauthors= |date=2007 |format= |work= |publisher=|pages= |language= |archiveurl= |archivedate= |quote= }}</ref><ref>{{cite book |title=Primate fact sheet|accessdate=2007-08-11|author=Primata|authorlink= |coauthors= |date=2007 |format= |work= |publisher=|pages= |language= |archiveurl= |archivedate= |quote= }}</ref>     
==Living Primate Species==<ref name="Fleagle"/><ref>{{cite web |url=http://www.theprimata.com/factsheets.html|title=Primate fact sheet|accessdate=2007-08-11|author=Primata|authorlink= |coauthors= |date=2007 |format= |work= |publisher=|pages= |language= |archiveurl= |archivedate= |quote= }}</ref><ref>{{cite book |title=Primate fact sheet|accessdate=2007-08-11|author=Primata|authorlink= |coauthors= |date=2007 |format= |work= |publisher=|pages= |language= |archiveurl= |archivedate= |quote= }}</ref>     


===PRIMATA===
====SUBORDER STREPSIRHINI====
=====INFRAORDER LEMURIFORMES=====
======Superfamily Lemuroidea======
======Family Cheirogaleidae======
*Fat-tailed Dwarf Lemur '' [[Cheirogaleus medius]] ''
*Southern Dwarf Lemur '' [[Cheirogaleus adipicaudatus]] ''
*Greater Dwarf Lemur '' [[Cheirogaleus major]] ''
*Furry-eared Dwarf Lemur '' [[Cheirogaleus crossleyi]] ''
*Small Iron-gray Dwarf Lemur [[Cheirogaleus minusculus]]
*Large Iron-gray Dwarf Lemur [[Cheirogaleus ravus]]
*Lesser Mouse Lemur [[Microcebus murinus]]
*Gray-brown Mouse Lemur [[Microcebus griseorufus]]
*Jolly's Mouse Lemur [[Microcebus jollyae]]
*Golden-brown Mouse Lemur [[Microcebus ravelobensis]]
*Simmons' Mouse Lemur [[Microcebus simmonsi]]
*Sambirano Mouse Lemur [[Microcebus sambiranensis]]
*Mittermeier's Mouse Lemur [[Microcebus mittermeieri]]
*Russet Mouse Lemur [[Microcebus rufus]]
*Berthe's Mouse Lemur [[Microcebus berthae]]
*Goodman's Mouse Lemur [[Microcebus lehilahytsara]]
*Northern Rufous Mouse Lemur [[Microcebus tavaratra]]
*Pygmy Mouse Lemur [[Microcebus myoxinus]]
*Coquerel's Mouse Lemur [[Mirza coquereli]]
*Northern Mouse Lemur [[Mirza zaza]]
*Hairy-eared Dwarf Lemur [[Allocebus trichotis]]
*Fork-crowned Lemur [[Phaner furcifer]]
======Family Lemuridae======
*Ring-tailed Lemur [[Lemur catta]]
*Black Lemur [[Eulemur macaco]]
*Brown Lemur [[Eulemur fulvus]]
*Mongoose Lemur [[Eulemur mongoz]]
*Crowned Lemur [[Eulemur coronatus]]
*Red-bellied Lemur [[Eulemur rubriventer]]
*Gray Gentle Lemur [[Hapalemur griseus]]
*Golden Gentle Lemur [[Hapalemur aureus]]
*Broad-nosed Gentle Lemur [[Hapalemur simus]]
*Ruffed Lemur [[Varecia variegate]]
======Family Megaladapidae======
*Weasel Sportive Lemur [[Lepilemur mustelinus]]
*Small-toothed Sportive Lemur [[Lepilemur microdon]]
*White-footed Sportive Lemur [[Lepilemur leucopus]]
*Red-tailed Sportive Lemur [[Lepilemur ruficaudatus]]
*Antafia Sportive Lemur [[Lepilemur aeeclis]]
*Randrianasolo's Sportive Lemur [[Lepilemur randrinanasoli]]
*Milne-Edwards Sportive Lemur [[Lepilemur edwardsi]]
*Gray-backed Sportive Lemur [[Lepilemur dorsalis]]
*Sahamalaza Peninsula Sportive Lemur [[Lepilemur sahamalazensis]]
*Northern Sportive Lemur [[Lepilemur septentrionalis]]
======Family Indriidae======
*Indri [[Indri indri]]
*Eastern Woolly Lemur [[Avahi laniger]]
*Western Woolly Lemur [[Avahi occidentalis]]
*Cleese's Woolly Lemur [[Avahi cleesei]]
*Unicolor Woolly Lemur [[Avahi unicolor]]
*Diademed Sifaka [[Propithecus diadema]]
*Verreaux's Sifaka [[Propithecus verreauxi]]
======Family Daubentoniidae======
*Aye-aye [[Daubentonia madagascariensis]]
=====Superfamily Lorisoidea=====
======Family Loridae======
*Calabar Potto [[Arctocebus calabarensis]]
*Golden Potto [[Arctocebus aureus]]
*Potto [[Perodicticus potto]]
*Martin's False Potto [[Pseudopotto martini]]
*Slender Loris [[Loris tardigradus]]
*Slow Loris [[Nycticebus coucang]]
*Lesser Slow Loris [[Nycticebus pygmaeus]]
======Family Galagonidae======
*Greater Galago [[Otolemur crassicaudatus]]
*Silvery Greater Galago [[Otolemur monteiri]]
*Garnett's Galago [[Otolemur garnettii]]
*Southern Needle-clawed Galago [[Euoticus elegantulus]]
*Northern Needle-clawed Galago [[Euoticus pallidus]]
*Eastern Needle-clawed Galago [[Euoticus inustus]]
*Lesser Galago [[Galago senegalensis]]
*Southern Lesser Galago [[Galago moholi]]
*Allen's Galago [[Galago alleni]]
*Zanzibar Galago [[Galago zanzibaricus]]
*Demidoff's Galago [[Galago demidoff]]
*Thomas's Galago [[Galago thomasi]]
====SUBORDER HAPLORRHINI====
=====INFRAORDER TARSIIFORMES=====
======Family Tarsiidae======
*Philippine Tarsier [[Tarsius syrichta]]
*Horsfield's Tarsier [[Tarsius bancanus]]
*Spectral Tarsier [[Tarsius spectrum]]
*Dian's Tarsier [[Tarsius dianae]]
*Lariang Tarsier [[Tarsius lariang]]
*Peleng Island Tarsier [[Tarsius pelengensis]]
*Sangihe Island Tarsier [[Tarsius sangirensis]]
*Pygmy Tarsier [[Tarsius pumilus]]
=====INFRAORDER PLATYRHINI=====
=====Superfamily Ceboidea=====
======Family Cebidae======
*Bolivian Titi [[Callicebus modestus]]
*Bolivian Gray Titi [[Callicebus donacophilus]]
*Beni Titi [[Callicebus olallae]]
*Andean Titi [[Callicebus oenanthe]]
*Ashy-gray Titi [[Callicebus cinerascens]]
*Hoffmann's Titi [[Callicebus hoffmannsi]]
*Dusky Titi [[Callicebus moloch]]
*Brown Titi [[Callicebus brunneus]]
*Madidi Titi [[Callicebus aureipalatii]]
*Chestnut Bellied Titi [[Callicebus caligatus]]
*Red Titi [[Callicebus cupreus]]
*Hershkovitz's Titi [[Callicebus dubius]]
*Masked Titi [[Callicebus personatus]]
*Collared Titi [[Callicebus torquatus]]
*Lemurine Owl Monkey [[Aotus lemurinus]]
*Brumback's Owl Monkey [[Aotus brumbacki]]
*Hershkovitz's Owl Monkey [[Aotus hershkovitzi]]
*Northern Owl Monkey [[Aotus trivirgatus]]
*Spix's Owl Monkey [[Aotus vociferans]]
*Andean Owl Monkey [[Aotus miconax]]
*Peruvian Red-necked Owl Monkey [[Aotus nancymae]]
*Black-headed Owl Monkey [[Aotus nigriceps]]
*Southern Owl Monkey [[Aotus azarae]]
*Kuhl's Owl Monkey [[Aotus infulatus]]
*White-faced Saki [[Pithecia pithecia]]
*Monk Saki [[Pithecia monachus]]
*Bald-faced Saki [[Pithecia irrorator]]
*Red-bearded Saki [[Pithecia aequatorialis]]
*Buffy Saki [[Pithecia albicans]]
*Black Saki [[Chiropotes satanas]]
*White-nosed Saki [[Chiropotes albinasus]]
*Black-headed Uakari [[Cacajao melanocephalus]]
*Red Uakari [[Cacajao calvus]]
*White-throated Capuchin [[Cebus capucinus]]
*White-fronted Capuchin [[Cebus albifrons]]
*Weeper Capuchin [[Cebus olivaceus]]
*Ka'apor Capuchin [[Cebus kaapori]]
*Black-capped Capuchin [[Cebus paella]]
*Red-backed Squirrel Monkey [[Saimiri oerstedi]]
*Common Squirrel Monkey [[Saimiri sciureus]]
*Golden-backed Squirrel Monkey [[Saimiri ustus]]
*Bolivian Squirrel Monkey [[Saimiri boliviensis]]
*Blackish Squirrel Monkey [[Saimiri vanzolinii]]
*Guatemalan Howler Monkey [[Alouatta pigra]]
*Mantled Howler Monkey [[Alouatta palliate]]
*Coiba Island Howler Monkey [[Alouatta coibensis]]
*Red Howler Monkey [[Alouatta seniculus]]
*Red-handed Howler Monkey [[Alouatta belzebul]]
*Brown Howler Monkey [[Alouatta fusca]]
*Black Howler Monkey [[Alouatta caraya]]
*Black Spider Monkey [[Ateles paniscus]]
*Long-haired Spider Monkey [[Ateles belzebuth]]
*Black-faced Spider Monkey [[Ateles chamek]]
*Brown-headed Spider Monkey [[Ateles fusciceps]]
*Black-handed Spider Monkey [[Ateles geoffroyi]]
*Woolly Spider Monkey [[Brachyteles arachnoids]]
*Humboldt's Woolly Monkey [[Lagothrix lagotricha]]
*Yellow-tailed Woolly Monkey [[Lagothrix flavicauda]]
======Family Callitrichidae======
*Goeldi's Marmoset [[Callimico goeldii]]
*Common Marmoset [[Callithrix jacchus]]
*Black Tufted-ear Marmoset [[Callithrix penicillata]]
*Wied's Marmoset [[Callithrix kuhli]]
*Geoffroy's Tufted-ear Marmoset [[Callithrix geoffroyi]]
*Buffy-headed Marmoset [[Callithrix flaviceps]]
*Buffy Tufted-ear Marmoset [[Callithrix aurita]]
*Silvery Marmoset [[Callithrix argentata]]
*Golden-white Bare-ear Marmoset [[Callithrix leucippe]]
*Snethlage's Marmoset [[Callithrix emiliae]]
*Black-headed Marmoset [[Callithrix nigriceps]]
*Black-tailed Marmoset [[Callithrix melanura]]
*Black-and-white Tassel-ear Marmoset [[Callithrix humeralifer]]
*Rio Maues Marmoset [[Callithrix mauesi]]
*Golden-white Tassel-ear Marmoset [[Callithrix chrysoleuca]]
*Tassel-ear Marmoset [[Callithrix intermedia]]
*Dwarf Marmoset [[Callithrix humilis]]
*Rio Acari Marmoset [[Callithrix acariensis]]
*Rio Manicore Marmoset [[Callithrix manicorensis]]
*Pygmy Marmoset [[Cebuella pygmaea]]
*Golden Lion Tamarin [[Leontopithecus rosalia ]]
*Golden-headed Lion Tamarin [[Leontopithecus chrysomelas ]]
*Golden-rumped Lion Tamarin [[Leontopithecus chrysopygus ]]
*Black-faced Lion Tamarin [[Leontopithecus caissara]]
*Midas Tamarin [[Saguinus midas ]]
*Black-mantle Tamarin [[Saguinus nigricollis]]
*Saddle-back Tamarin [[Saguinus fuscicollis]]
*Golden-mantle Saddle-back Tamarin [[Saguinus tripartitus]]
*Black-chested Moustached Tamarin [[Saguinus mystax ]]
*Red-bellied Tamarin [[Saguinus labiatus ]]
*Emperor Tamarin [[Saguinus imperator]]
*Pied Tamarin [[Saguinus bicolour]]
*Cotton-top Tamarin [[Saguinus oedipus ]]
*Geoffroy's Tamarin [[Saguinus geoffroyi]]
*White-footed Tamarin [[Saguinus leucopus]]
*Mottle-face Tamarin [[Saguinus inustus]]
=====INFRAORDER CATARRHINI=====
=====Superfamily Hominoidea=====


======Family Hylobatidae======
*White-handed Gibbon [[Hylobates lar]]
*Agile Gibbon [[Hylobates agilis]]
*Mueller's Gibbon [[Hylobates muelleri]]
*Moloch Gibbon [[Hylobates moloch]]
*Pileated Gibbon [[Hylobates pileatus]]
*Kloss' Gibbon [[Hylobates klossii]]
*Hoolock Gibbon [[Hylobates hoolock]]
*Black Gibbon [[Hylobates concolor]]
*Siamang [[Hylobates syndactylus]]
======Family Hominidae======
*Orang-Utan [[Pongo pygmaeus]]
*Gorilla [[Gorilla gorilla]]
*Pygmy Chimpanzee (Bonobo) [[Pan paniscus]]
*Common Chimpanzee [[Pan troglodytes]]
=====Superfamily Cercopithecoidea=====
======Family Cercopithecidae======
======Subfamily Cercopithecinae======
*Allen's Swamp Monkey [[Allenopithecus nigroviridis]]
*Talapoin Monkey [[Miopithecus talapoin]]
*Patas Monkey [[Erythrocebus patas]][[Image:Vervet monkey.jpg|thumb|right|200px|A vervet monkey (Cercopithecus aethiops). South Africa.]]
*Vervet Monkey [[Cercopithecus aethiops]]
*Dryas Monkey [[Cercopithecus dryas]]
*Zaire Diana Monkey [[Cercopithecus salongo]]
*Diana Monkey [[Cercopithecus diana]]
*Greater White-nosed Monkey [[Cercopithecus nictitans]]
*Blue Monkey [[Cercopithecus mitis]]
*Mona Monkey [[Cercopithecus mona]]
*Campbell's Monkey [[Cercopithecus campbelli]]
*Crowned Guenon [[Cercopithecus pogonias]]
*Wolf's Monkey [[Cercopithecus wolfi]]
*Lesser White-nosed Monkey [[Cercopithecus petaurista]]
*Red-bellied Monkey [[Cercopithecus erythrogaster]]
*Sclater's Monkey [[Cercopithecus sclateri]]
*Red-eared Nose-spotted Monkey [[Cercopithecus erythrotis]]
*Moustached Monkey [[Cercopithecus cephus]]
*Redtail Monkey [[Cercopithecus ascanius]]
*L'hoest's Monkey [[Cercopithecus lhoesti]]
*Preuss's Monkey [[Cercopithecus preussi]]
*Sun-tailed Monkey [[Cercopithecus solatus]]
*Hamlyn's Monkey [[Cercopithecus hamlyni]]
*DeBrazza's Monkey [[Cercopithecus neglectus]]
*Barbary Macaque [[Macaca sylvanus]]
*Lion-tailed Macaque [[Macaca silenus]]
*Pigtailed Macaque [[Macaca nemestrina]]
*Mentawai Macaque [[Macaca pagensis]]
*Moor Macaque [[Macaca maura]]
*Ochre Macaque [[Macaca ochreata]]
*Muna-Butung Macaque [[Macaca brunescens]]
*Tonkean Macaque [[Macaca tonkeana]]
*Heck's Macaque [[Macaca hecki]]
*Gorontalo Macaque [[Macaca nigriscens]]
*Celebes Macaque [[Macaca nigra]]
*Crab-eating Macaque [[Macaca fascicularis]]
*Stumptailed Macaque [[Macaca arctoides]]
*Rhesus Macaque [[Macaca mulatta]]
*Formosan Rock Macaque [[Macaca cyclopis]]
*Japanese Macaque [[Macaca fuscata]]
*Toque Macaque [[Macaca sinica]]
*Bonnet Macaque [[Macaca radiate]]
*Assamese Macaque [[Macaca assamensis]]
*Arunachal Macaque [[Macaca munzala]]
*Pere David's Macaque [[Macaca thibetana]]
*Gray-cheeked Mangabey [[Lophocebus albigena]]
*Highland Mangabey [[Lophocebus kipunji]]
*Black Mangabey [[Lophocebus aterrimus]]
*Hamadryas Baboon [[Papio hamadryas]]
*Guinea Baboon [[Papio papio]]
*Olive Baboon [[Papio anubis]]
*Yellow Baboon [[Papio cynocephalus]]
*Chacma Baboon [[Papio ursinus]]
*Gelada Baboon [[Theropithecus gelada]]
*Sooty Mangabey [[Cercocebus atys]]
*White-collared Mangabey [[Cercocebus torquatus]]
*Agile Mangabey [[Cercocebus agilis]]
*Tana River Mangabey [[Cercocebus galeritus]]
*Mandrill [[Mandrillus sphinx]]
*Drill [[Mandrillus leucophaeus]]
======Subfamily Colobinae======
*Black Colobus Monkey [[Colobus satanas]]
*Angolan Black-and-white Colobus Monkey [[Colobus angolensis]]
*Western Black-and-white Colobus Monkey [[Colobus polykomos]]
*Geoffroy's Black-and-white Colobus Monkey [[Colobus vellerosus]]
*Abyssinian Black-and-white Colobus Monkey [[Colobus guereza]]
*Western Red Colobus Monkey [[Procolobus badius]]
*Pennant's Red Colobus Monkey [[Procolobus pennantii]]
*Preuss's Red Colobus Monkey [[Procolobus preussi]]
*Tana River Red Colobus Monkey [[Procolobus rufomitratus]]
*Olive Colobus Monkey [[Procolobus verus]]
*Hanuman Langur [[Semnopithecus entellus]]
*Purple-faced Langur [[Trachypithecus vetulus]]
*Nilgiri Langur [[Trachypithecus johnii]]
*Javan Langur [[Trachypithecus auratus]]
*Silvered Leaf-monkey [[Trachypithecus cristatus]]
*Tenasserim Langur [[Trachypithecus barbei]]
*Dusky Leaf-monkey [[Trachypithecus obscurus]]
*Phayre's Leaf-monkey [[Trachypithecus phayrei]]
*Capped Langur [[Trachypithecus pileatus]]
*Golden Langur [[Trachypithecus geei]]
*Francois' Leaf-monkey [[Trachypithecus francoisi]]
*Hatinh Langur [[Trachypithecus hatinhensis]]
*White-headed Langur [[Trachypithecus poliocephalus]]
*Laotian Langur [[Trachypithecus laotum]]
*Delacour's Langur [[Trachypithecus delacouri]]
*Mitered Leaf-monkey [[Presbytis melalophos]]
*Banded Leaf-monkey [[Presbytis femoralis]]
*White Fronted Leaf-monkey [[Presbytis frontata]]
*Grizzled Leaf-monkey [[Presbytis comata]]
*Thomas's Leaf-monkey [[Presbytis thomasi]]
*Hose's Leaf-monkey [[Presbytis hosei]]
*Maroon Leaf-monkey [[Presbytis rubicunda]]
*Mentawai Island Leaf-monkey [[Presbytis potenziani]]
*Douc Langur [[Pygathrix nemaeus]]
*Snub-nosed Langur [[Pygathrix roxellana]]
*Black Snub-nosed Langur [[Pygathrix bieti]]
*Brelich's Snub-nosed Langur [[Pygathrix brelichi]]
*Tonkin Snub-nosed Langur [[Pygathrix avunculus]]
*Proboscis Monkey [[Nasalis larvatus]]
*Pig-tailed Langur [[Nasalis concolor]]


==References==
==References==
 
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Primates
Fossil range: Paleocene - Recent
An "Old World" monkey - Papio anubis. This male baboon at Ngorongoro Crater, Tanzania is holding an infant.
An "Old World" monkey - Papio anubis. This male baboon at Ngorongoro Crater, Tanzania is holding an infant.
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Infraclass: Eutheria
Superorder: Euarchontoglires
Order: Primates
Linnaeus, 1758

Primates are an order of mammals which in living diversity include, prosimians (galagos, lorises, lemurs and tarsiers), platyrrhines (New World monkeys), cercopithecids (Old World monkeys) and hominoids (apes and humans). They have their origins in some type of an insectivorous mammal that lived in the late Cretaceous[1][2].

Description

All primates have a primitive dental plan, five fingers, nails instead of claws, a thumb and a generalized body plan. All primates share a similar eye orbit morphology and have a post-orbital bar[2]. All primates have forward facing eyes[3].

Geographical distribution

Due to the recent spread of humans in the last 12,000 years, primates are a probably the most geographically distributed mammal, occupying every continent. Non-human primates are indigenous to South and Central America, Africa, Asia and the the islands of Indonesia.

Prosimians

Prosimian primates are the most primitive of living primates and share many morphological characteristics with other mammals such as tree shrews and bats[2]. The greatest diversity of prosimian primates is found on the island of Madagascar[4], but all species of living prosimian species are found only in the Old World.

Lemurs

Lemurs exist only on the island of Madagascar and the neighbouring islands of the Comores. They are among the most primitive of primates. They have moist noses and reflective eyes. They range in body size from the 30 gram Pygmy lemur to the 10kg Indri. Due to their geographically restricted range and destruction of habitat by humans, all lemur species are endangered[1][2].

Lorises

Lorises are arboreal prosimian primates who live in India and southeast Asia. They live in tropical areas, typically high in the canopy and rarely come to the ground[1][2]. They are known to be very slow moving.

Galagos

Galagos, also known as bushbabies, are small, arboreal nocturnal primates with large eyes. They are native to Africa. Bushbabies are extremely adept leapers[1].

Tarsiers

Tarsiers are a nocturnal, arboreal primate restricted to several islands in southeast Asia. They are primarily insectiverous and are agile leapers. Unlike most nocturnal primates, they have non-reflective eyes.

Monkeys

There are two basic types of monkeys - platyrrhines and catarrhines. South American monkeys are known as platyrrhines and differ considerably from the catarrhines monkeys, having evolved largely in isolation[1][2].

Platyrrhine monkeys

The name platyrrhine derives from the broad, flat shape of their external nostrils. All platyrrhines are small, the largest is only around 10kg[1]. They also exhibit many primitive dental and skeletal features including having three pre-molars[2].

All platyrrhines have a tail of some sort and five genera have prehensile tails[1], the most well known of these probably being the spider monkey.

Catarrhine monkeys

Catarrhines monkeys are "Old World Monkeys" and all fall under the Superfamily Cercopithecidae[2]. They have narrow noses, eight pre-molars and none have prehensile tails[1]. There are two Subfamilies within the Superfamily - Cercopithecinae and Colobinae[2]. There are approximately sixty species of cercopithicus monkey and about forty species of Colobus monkey.

Apes and humans

The living apes are generally considered to be primates who are tailess, of relatively large body size and all live in the old world. Typically included in the grouping "apes" are gibbons and siamangs from southeast Asia, Orangutans from Borneo and Sumatra, Mountain and Lowland Gorillas, Chimpanzees and Bonobos and humans. Under the modern genetic classification scheme (see Hominini for more on this), apes are in the superfamily Hominoidea. Underneath this hominoid umbrella falls orang-utans, gorillas, chimps and humans in the Family Hominidae. In recognition of their genetic divergence some 11-13 million years ago, the orangutans are placed in the sub-family Ponginae and the African apes, including humans, are lumped together in the Subfamily Homininae. The bipedal apes, namely all of the fossil species as well as living humans, fall into the Tribe Hominini[5]. Some evolutionary biologists include humans and chimpanzees within the same genus, the genus Homo. The more traditional Linnaean clasification of primates may be found in the "List of Primate Species" at the end of this article.

Primate evolution

The earliest possible primate discovered so far comes from North America and is about 60 million years old[1][2]. Named Purgatorius, this tiny insectivore is only loosely morphologically allied with later primates[2]. There are possible older Purgatorius specimens going back into the latest Cretaceous, but most are from dubious context. It is only in the late Paleocene (about 55 million years ago) that we see more numerous remains of primate-like animals appearing in the fossil record[1][2].

Known as the Plesiadapiforms these near-primates appear to have evolved in North America and Europe[2]. The Plesiadapiforms radiated into many different niches, but in the early Eocene (about 45 to 50 million years ago), it seems that the rise of rodents caused a rapid decline in the number and diversity of Plesiadapiforms[2]. But Plesiadapiforms are probably not the ancestors of living primates, as they possessed too many specializations to have given rise to the first Prosimian primates that would appear a few million years later[2]. So at this time, the only primate-like mammal that is a firm candidate as ancestor of all higher primates is the tiny Purgatorius.

The first true prosimian primates appeared, and exploded in diversity, in the early Eocene Epoch (between 54 and 38 million years ago)[1]. Eocene aged Prosimian primates are commonly found in North America and Europe and more rarely in Asia and Africa. No early primates have ever been found in South America or Antarctica as the former was an island continent, while we have as of yet found fossil deposits of this age in the latter[2]. In these earliest primates the bony ring around the orbit was complete like in modern primates, nails replaced claws and larger brains were evolved. These early Eocene primates were clearly true primates and took two distinct forms: lemur-like adapids and galago- (bushbaby) like omomyids[1]. Although the living forms are different species, these animals descendants can clearly be seen in the lemurs of Madagascar and the galagos, lorises and tarsiers of Africa and Asia.

As the Eocene drew to a close and the Oligocene epoch began about 37 million years ago, the continents were approaching their modern form and position, with the exception that there was no land bridge between South America and North America[1][2]. The world was however, in a state of geographical transition. India was colliding with the continent of Asia, lifting the great Himalayas[6]. South America and Australia had pulled away from Antarctica and formed independent island continents. Deep water currents could thus circulate around Antarctica, bringing cold waters northward and subsequently cooling the oceans of the world. At the same time, the rise of the Himalayas blocked the northward curve of the jet stream, changing the climate south of this great mountain range[6].

Primates in Europe suddenly go extinct while in North America their fossils become increasingly rare and there is a general decline in mammalian diversity[2]. Until recently, the global climatic changes of the early Oligocene have been blamed almost wholly on the mammalian extinctions that occurred at this time, but in November of 2001, scientists from the United States Geological Service announced that what was previously thought to be a relatively small extraterrestrial impact in the Chesapeake Bay area was in fact quite large (around 137 kilometers in diameter), and struck at approximately 35 million years ago[7], right at the point of extinction of many of the North American primates and at a point of general loss of mammalian diversity[8].

A primate puzzle

Prior to about 30 million years ago there are no primates or even primate-like animals in South America[1][2]. Around 25 to 30 million years ago a wide variety of new forms of mammal suddenly appear in South America but it is unknown where they come from[2]. Among the new forms are rare fossil primates which look very much like existing Platyrrhines[2]. As the only major difference in continental position between that of today and then was that no land bridge existed between North and South America, any introduction of primates into South America would require some form of open water crossing, possibly rafting on large fallen tree trunks or large mats of vegetation[9]. Because of relatively shallow water in the South Atlantic during lower sea level periods, there were almost certainly many islands exposed between Africa and South America, effectively bringing the two continents much closer together and making potential rafting hops shorter. In fact, most geophysicists suggest that at the time the open water distance between North America and South America was probably greater than that between the latter and Africa[9].

Predications of current direction also tentatively support a West to East crossing rather than a North to South rafting event[9]. The fossil record also supports an “Out of Africa theory by raft” for the origin of Platyrrhines. At this time, there are simply no known primates advanced enough in North America to be suitable ancestral candidates of the early Platyrrhines[2][9], but Africa has a host of possible ancestral Platyrrhine forms. Further tantalizing evidence of an African connection is the fact that the closest living relatives of South American rodents are the African Hystricids, more commonly known as porcupines[9][2].

Another possible source for Platyrrhine origins would be Antarctica, but we know nothing about the later fossil record, if it exists at all, of Antarctica at this time[9][2]. The same may be said about Asia, where there is presently little or no evidence for Platyrrhine origins[9][2].

==Living Primate Species==[1][10][11]


References

  1. ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 J. Fleagle (1998). Primate Adaptation and Evolution. Academic Press: New York. 
  2. ↑ 2.00 2.01 2.02 2.03 2.04 2.05 2.06 2.07 2.08 2.09 2.10 2.11 2.12 2.13 2.14 2.15 2.16 2.17 2.18 2.19 2.20 2.21 2.22 2.23 2.24 F. Szalay and E. Delson (2001). Evolutionary History of the Primates. Academic Press, New York. 
  3. ↑ S. Lovgren (2006). Snake Threat May Have Spurred Evolution of Primate Eyes. National Geographic. Retrieved on 2007-08-10.
  4. ↑ Wild Madagascar (2005). Madagascar lemurs descended from single primate ancestor. Wildmadagascar.com. Retrieved on 2007-08-10.
  5. ↑ L.R. Berger (2001). Is it time to revise the system of scientific naming. National Geographic. Retrieved on 2007-08-10.
  6. ↑ 6.0 6.1 >R. Bilham (2000). Birth of the Himilaya. PBS. Retrieved on 2007-08-11.
  7. ↑ USGS (2001). The Chesapeake Meteorite: Message from the Past. Retrieved on 2007-08-11.
  8. ↑ Primata (2007). Primate fact sheet. Retrieved on 2007-08-11. 
  9. ↑ 9.0 9.1 9.2 9.3 9.4 9.5 9.6 R.L. Ciochon and A.B. Chiarelli (1981). Evolutionary Biology of the New World Monkeys and Continental Drift. Plenum Pub Corp, 528p. 
  10. ↑ Primata (2007). Primate fact sheet. Retrieved on 2007-08-11.
  11. ↑ Primata (2007). Primate fact sheet. Retrieved on 2007-08-11. 
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