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{{pp-pc|small=yes}}
{{Short description|Species of mammal}}
{{Short description|Species of mammal}}
{{about|the animal}}
{{About|the animal}}
{{good article}}
{{pp-pc}}
{{Good article}}
{{Use dmy dates|date=October 2020}}
{{Use dmy dates|date=October 2020}}
{{Speciesbox
{{Speciesbox
| name = Okapi
| name = Okapi
| image = Saint-Aignan (Loir-et-Cher). Okapi.jpg
| image = Saint-Aignan (Loir-et-Cher). Okapi.jpg
| image_caption = At [[ZooParc de Beauval|Beauval Zoo]]
| image_caption = Male okapi at [[ZooParc de Beauval|Beauval Zoo]]
| image2 = Okapia johnstoni 17zz.jpg
| image2_caption = Female okapi at [[Zoo Miami]]
| status = EN
| status = EN
| status_system = IUCN3.1
| status_system = IUCN3.1
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}}
}}


The '''okapi''' ({{IPAc-en|oʊ|ˈ|k|ɑː|p|iː}}; '''''Okapia johnstoni'''''), also known as the '''forest giraffe''', '''Congolese giraffe''', or '''zebra giraffe''', is an [[artiodactyl]] [[mammal]] that is [[endemic]] to the northeast [[Democratic Republic of the Congo]] in central Africa. It is the [[monotypic taxon|only species]] in the [[genus]] '''''Okapia'''''. Although the okapi has striped markings reminiscent of [[zebra]]s, it is most closely related to the [[giraffe]]. The okapi and the giraffe are the only living members of the family [[Giraffidae]]. The okapi is a result of a giraffe mating with a zebra.
The '''okapi''' ({{IPAc-en|oʊ|ˈ|k|ɑː|p|iː}}; '''''Okapia johnstoni'''''), also known as the '''forest giraffe''', '''Congolese giraffe''' and '''zebra giraffe''', is an [[artiodactyl]] [[mammal]] that is [[endemic]] to the northeast [[Democratic Republic of the Congo]] in central Africa. However, non-invasive genetic identification has suggested that a population has occurred south-west of the Congo River as well.<ref>{{cite journal |last1=Stanton |first1=D. |last2=Hart |first2=J. |last3=Vosper |first3=A. |last4=Kümpel |first4=N. |last5=Wang |first5=J. |last6=Ewen |first6=J. |last7=Bruford |first7=M. |year=2016 |title=Non-invasive genetic identification confirms the presence of the Endangered okapi Okapia johnstoni south-west of the Congo River |journal=Oryx |volume=50 |issue=1 |pages=134–137 |doi=10.1017/S0030605314000593|doi-access=free }}</ref> It is the [[monotypic taxon|only species]] in the [[genus]] '''''Okapia'''''. Although the okapi has striped markings reminiscent of [[zebra]]s, it is most closely related to the [[giraffe]]. The okapi and the giraffe are the only living members of the family [[Giraffidae]].


The okapi stands about {{cvt|1.5|m|}} tall at the shoulder and has a typical body length around {{cvt|2.5|m|}}. Its weight ranges from {{cvt|200|to|350|kg|}}. It has a long neck, and large, flexible ears. Its coat is a chocolate to reddish brown, much in contrast with the white horizontal stripes and rings on the legs, and white ankles. Male okapis have short, distinct horn-like protuberances on their heads called [[ossicone]]s, less than {{convert|15|cm|in|abbr=on}} in length. Females possess [[hair whorl]]s, and ossicones are absent.
The okapi stands about {{cvt|1.5|m|}} tall at the shoulder and has a typical body length around {{cvt|2.5|m|}}. Its weight ranges from {{cvt|200|to|350|kg|}}. It has a long neck, and large, flexible ears. Its coat is a chocolate to reddish brown, much in contrast with the white horizontal stripes and rings on the legs, and white ankles. Male okapis have short, distinct horn-like protuberances on their heads called [[ossicone]]s, less than {{convert|15|cm|in|abbr=on}} in length. Females possess [[hair whorl]]s, and ossicones are absent.


Okapis are primarily [[Diurnal animal|diurnal]], but may be active for a few hours in darkness. They are essentially solitary, coming together only to breed. Okapis are [[herbivore]]s, feeding on tree leaves and buds, grasses, ferns, fruits, and [[fungus|fungi]]. Rut in males and estrus in females does not depend on the season. In captivity, estrus cycles recur every 15 days. The [[gestational period]] is around 440 to 450 days long, following which usually a single calf is born. The juveniles are kept in hiding, and nursing takes place infrequently. Juveniles start taking solid food from three months, and weaning takes place at six months.
Okapis are primarily [[Diurnality|diurnal]], but may be active for a few hours in darkness. They are essentially solitary, coming together only to breed. Okapis are [[herbivore]]s, feeding on tree leaves and buds, grasses, ferns, fruits, and [[fungus|fungi]]. Rut in males and estrus in females does not depend on the season. In captivity, estrus cycles recur every 15 days. The [[gestational period]] is around 440 to 450 days long, following which usually a single calf is born. The juveniles are kept in hiding, and nursing takes place infrequently. Juveniles start taking solid food from three months, and weaning takes place at six months.


Okapis inhabit [[canopy (biology)|canopy]] forests at altitudes of {{cvt|500|-|1500|m|}}. The [[International Union for the Conservation of Nature and Natural Resources]] classifies the okapi as [[endangered]]. Major threats include habitat loss due to [[logging]] and human settlement. [[Illegal mining]] and extensive hunting for bushmeat and skin have also led to a decline in populations. The [[Okapi Conservation Project]] was established in 1987 to protect okapi populations.
Okapis inhabit [[canopy (biology)|canopy]] forests at altitudes of {{cvt|500|-|1500|m|}}. The [[International Union for the Conservation of Nature and Natural Resources]] classifies the okapi as [[endangered]]. Major threats include habitat loss due to [[logging]] and human settlement. [[Illegal mining]] and extensive hunting for bushmeat and skin have also led to a decline in populations. The [[Okapi Conservation Project]] was established in 1987 to protect okapi populations.


==Etymology and taxonomy==
==Etymology and taxonomy==
[[File: Pieces from Okapi leather, obtained by Sir Harry Johnston (crop).jpg|thumb|left|Strips cut from the striped part of the skin of an okapi, sent home by Sir [[Harry Johnston]], were the first evidence of the okapi's existence to reach Europe]]
[[File: Pieces from Okapi leather, obtained by Sir Harry Johnston (crop).jpg|thumb|left|Strips cut from the striped part of the skin of an okapi, sent home by Sir [[Harry Johnston]], were the first evidence of the okapi's existence to reach Europe.]]
Although the okapi was unknown to the Western world until the 20th century, it may have been depicted since the early fifth century BCE on the [[façade]] of the [[Apadana]] at [[Persepolis]], a gift from the Ethiopian procession to the [[Achaemenid]] kingdom.<ref>[http://oi.uchicago.edu/museum/collections/pa/persepolis/apadana.html The Oriental Institute of the University of Chicago, Photographic Archives]; [http://oi.uchicago.edu/gallery/pa_iran_paai_per_apa/index.php/2C9_72dpi.png?action=big&size=resize&fromthumbnail=true photo detail]. The Oriental Institute identifies the subject as an Okapi with a question mark.</ref>
Although the okapi was unknown to the Western world until the 20th century, it may have been depicted since the early fifth century BCE on the [[façade]] of the [[Apadana]] at [[Persepolis]], a gift from the Ethiopian procession to the [[Achaemenid]] kingdom.<ref>[http://oi.uchicago.edu/museum/collections/pa/persepolis/apadana.html The Oriental Institute of the University of Chicago, Photographic Archives] {{Webarchive|url=https://web.archive.org/web/20080708195251/http://oi.uchicago.edu/museum/collections/pa/persepolis/apadana.html |date=8 July 2008 }}; [http://oi.uchicago.edu/gallery/pa_iran_paai_per_apa/index.php/2C9_72dpi.png?action=big&size=resize&fromthumbnail=true photo detail] {{Webarchive|url=https://web.archive.org/web/20140221130911/http://oi.uchicago.edu/gallery/pa_iran_paai_per_apa/index.php/2C9_72dpi.png?action=big&size=resize&fromthumbnail=true |date=21 February 2014 }}. The Oriental Institute identifies the subject as an Okapi with a question mark.</ref><ref>{{Cite web |title=Ethiopian Delegation, Apadana Staircase, Persepolis by Richard Stone |url=https://pbase.com/rjstone/image/153898896 |access-date=2023-03-04 |website=PBase |language=en-US}}</ref>


For years, Europeans in Africa had heard of an animal that they came to call the African [[unicorn]].<ref>{{Cite web|url=https://www.zmescience.com/science/biology/first-pictures-of-the-okapi-or-the-african-unicorn/|title=First pictures of the okapi or the African 'unicorn'|date=2008-09-12|website=ZME Science|language=en-US|access-date=2020-02-20}}</ref><ref>{{Cite web|url=https://www.nrdc.org/onearth/new-deal-okapi-africas-unicorn|title=A New Deal for the Okapi, Africa's "Unicorn"|website=NRDC|language=en|access-date=2020-02-20}}</ref> The animal was brought to prominent European attention by speculation on its existence found in press reports covering [[Henry Morton Stanley]]'s journeys in 1887. In his travelogue of exploring the Congo, Stanley mentioned a kind of [[donkey]] that the natives called the ''atti''<!--The Ancient Greek word ati means horse{{dub}}-->, which scholars later identified as the okapi.{{cn|date=November 2022}}
For years, Europeans in Africa had heard of an animal that they came to call the African [[unicorn]].<ref>{{Cite web|url=https://www.zmescience.com/science/biology/first-pictures-of-the-okapi-or-the-african-unicorn/|title=First pictures of the okapi or the African 'unicorn'|date=2008-09-12|website=ZME Science|language=en-US|access-date=2020-02-20}}</ref><ref>{{Cite web|url=https://www.nrdc.org/onearth/new-deal-okapi-africas-unicorn|title=A New Deal for the Okapi, Africa's "Unicorn"|website=NRDC|date=13 December 2019 |language=en|access-date=2020-02-20}}</ref> The animal was brought to prominent European attention by speculation on its existence found in press reports covering [[Henry Morton Stanley]]'s journeys in 1887. In his travelogue of exploring the Congo, Stanley mentioned a kind of [[donkey]] that the natives called the ''atti''<!--The Ancient Greek word ati means horse{{dub}}-->, which scholars later identified as the okapi.{{citation needed|date=November 2022}}


When the British special commissioner in Uganda, [[Harry Johnston|Sir Harry Johnston]], discovered some [[African Pygmies|Pygmy]] inhabitants of the Congo being abducted by a showman for exhibition, he rescued them and promised to return them to their homes. The Pygmies fed Johnston's curiosity about the animal mentioned in Stanley's book. Johnston was puzzled by the okapi tracks the natives showed him; while he had expected to be on the trail of some sort of forest-dwelling horse, the tracks were of a cloven-hoofed beast.<ref>{{Cite news|url=https://www.earthtouchnews.com/conservation/endangered/new-hope-for-the-elusive-okapi-congos-mini-giraffe/|title=New hope for the elusive okapi, Congo's mini giraffe|work=Earth Touch News Network|access-date=2017-11-09|language=en}}</ref>
When the British special commissioner in Uganda, [[Harry Johnston|Sir Harry Johnston]], discovered some [[African Pygmies|Pygmy]] inhabitants of the Congo being abducted by a showman for exhibition, he rescued them and promised to return them to their homes. The Pygmies fed Johnston's curiosity about the animal mentioned in Stanley's book. Johnston was puzzled by the okapi tracks the natives showed him; while he had expected to be on the trail of some sort of forest-dwelling horse, the tracks were of a cloven-hoofed beast.<ref>{{Cite news|url=https://www.earthtouchnews.com/conservation/endangered/new-hope-for-the-elusive-okapi-congos-mini-giraffe/|title=New hope for the elusive okapi, Congo's mini giraffe|work=Earth Touch News Network|access-date=2017-11-09|language=en}}</ref>
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In 1901, Sclater presented a painting of the okapi before the [[Zoological Society of London]] that depicted its physical features with some clarity. Much confusion arose regarding the taxonomical status of this newly discovered animal. Sir Harry Johnston himself called it a ''[[Helladotherium]]'', or a relative of other extinct giraffids.<ref>{{cite journal|title=Proceedings of the general meetings for scientific business of the Zoological Society of London|journal=[[Proceedings of the Zoological Society of London]]|date=1901|volume=2|issue=1|pages=1–5|url=https://archive.org/stream/proceedingsofzoo19012zool#page/n47/mode/2up}}(May to December)</ref> Based on the description of the okapi by Pygmies, who referred to it as a "horse", Sclater named the species ''[[Equus (genus)|Equus]] johnstoni''.<ref name=kingdon1979>{{cite book|last1=Kingdon|first1=Jonathan|title=East African Mammals: An Atlas of Evolution in Africa, Volume 3, Part B|date=1979|publisher=University of Chicago Press|location=Chicago|isbn=9780226437224|page=339}}</ref> Subsequently, zoologist [[Ray Lankester]] declared that the okapi represented an unknown genus of the [[Giraffidae]], which he placed in its own genus, ''Okapia'', and assigned the name ''Okapia johnstoni'' to the species.<ref name=prothero>{{cite book|last1=Prothero|first1=Donald R.|last2=Schoch|first2=Robert M.|title=Horns, tusks, and flippers : the evolution of hoofed mammals|date=2002|publisher=Johns Hopkins University Press|location=Baltimore, Md.|isbn=9780801871351|pages=66–67}}</ref>
In 1901, Sclater presented a painting of the okapi before the [[Zoological Society of London]] that depicted its physical features with some clarity. Much confusion arose regarding the taxonomical status of this newly discovered animal. Sir Harry Johnston himself called it a ''[[Helladotherium]]'', or a relative of other extinct giraffids.<ref>{{cite journal|title=Proceedings of the general meetings for scientific business of the Zoological Society of London|journal=[[Proceedings of the Zoological Society of London]]|date=1901|volume=2|issue=1|pages=1–5|url=https://archive.org/stream/proceedingsofzoo19012zool#page/n47/mode/2up}}(May to December)</ref> Based on the description of the okapi by Pygmies, who referred to it as a "horse", Sclater named the species ''[[Equus (genus)|Equus]] johnstoni''.<ref name=kingdon1979>{{cite book|last1=Kingdon|first1=Jonathan|title=East African Mammals: An Atlas of Evolution in Africa, Volume 3, Part B|date=1979|publisher=University of Chicago Press|location=Chicago|isbn=9780226437224|page=339}}</ref> Subsequently, zoologist [[Ray Lankester]] declared that the okapi represented an unknown genus of the [[Giraffidae]], which he placed in its own genus, ''Okapia'', and assigned the name ''Okapia johnstoni'' to the species.<ref name=prothero>{{cite book|last1=Prothero|first1=Donald R.|last2=Schoch|first2=Robert M.|title=Horns, tusks, and flippers : the evolution of hoofed mammals|date=2002|publisher=Johns Hopkins University Press|location=Baltimore, Md.|isbn=9780801871351|pages=66–67}}</ref>


In 1902, Swiss zoologist [[Charles Immanuel Forsyth Major]] suggested the inclusion of ''O. johnstoni'' in the extinct giraffid subfamily [[Palaeotragus|Palaeotraginae]]. However, the species was placed in its own subfamily Okapiinae, by Swedish [[palaeontologist]] [[Birger Bohlin]] in 1926,<ref>{{cite journal|last1=Bohlin|first1=B.|title=Die Familie Giraffidae: mit besonderer Berücksichtigung der fossilen Formen aus China|journal=Palaeontologica Sinica, Series C|date=1926|volume=4|pages=1–179}}</ref> mainly due to the lack of a [[Cingulum (tooth)|cingulum]], a major feature of the palaeotragids.<ref name=colbert>{{cite journal|last1=Colbert|first1=E. H.|title=The relationships of the okapi|journal=Journal of Mammalogy|date=February 1938|volume=19|issue=1|pages=47–64|doi=10.2307/1374281|jstor=1374281}}</ref> In 1986, ''Okapia'' was finally established as a sister genus of ''[[Giraffa]]'' on the basis of [[cladistics|cladistic]] analysis. The two genera together with ''[[Palaeotragus]]'' constitute the tribe Giraffini.<ref name=geraads>{{cite journal |last1=Geraads |first1=Denis |title=Remarques sur la systématique et la phylogénie des Giraffidae (Artiodactyla, Mammalia) |journal=Geobios |date=January 1986 |volume=19 |issue=4 |pages=465–477 |doi=10.1016/S0016-6995(86)80004-3 }}</ref>
In 1902, Swiss zoologist [[Charles Immanuel Forsyth Major]] suggested the inclusion of ''O. johnstoni'' in the extinct giraffid subfamily [[Palaeotragus|Palaeotraginae]]. However, the species was placed in its own subfamily Okapiinae, by Swedish [[palaeontologist]] [[Birger Bohlin]] in 1926,<ref>{{cite journal|last1=Bohlin|first1=B.|title=Die Familie Giraffidae: mit besonderer Berücksichtigung der fossilen Formen aus China|journal=Palaeontologica Sinica, Series C|date=1926|volume=4|pages=1–179}}</ref> mainly due to the lack of a [[Cingulum (tooth)|cingulum]], a major feature of the palaeotragids.<ref name=colbert>{{cite journal|last1=Colbert|first1=E. H.|title=The relationships of the okapi|journal=Journal of Mammalogy|date=February 1938|volume=19|issue=1|pages=47–64|doi=10.2307/1374281|jstor=1374281}}</ref> In 1986, ''Okapia'' was finally established as a sister genus of ''[[Giraffa]]'' on the basis of [[cladistics|cladistic]] analysis. The two genera together with ''[[Palaeotragus]]'' constitute the tribe Giraffini.<ref name=geraads>{{cite journal |last1=Geraads |first1=Denis |title=Remarques sur la systématique et la phylogénie des Giraffidae (Artiodactyla, Mammalia) |journal=Geobios |date=January 1986 |volume=19 |issue=4 |pages=465–477 |doi=10.1016/S0016-6995(86)80004-3 |bibcode=1986Geobi..19..465G }}</ref>


===Evolution===
===Evolution===
[[File:Okapi Giraffe Neck.png|thumb|upright|Despite the vast difference in neck length, the okapi (left) and the giraffe (right) both have seven [[cervical vertebrae]] (as do all mammals except for manatees and sloths).]]
[[File:Okapi Giraffe Neck.png|thumb|upright|Despite the vast difference in neck length, the okapi (left) and the giraffe (right) both have seven [[cervical vertebrae]] (as do all mammals except for manatees and sloths).]]
The earliest members of the Giraffidae first appeared in the early [[Miocene]] in Africa, having diverged from the superficially deer-like [[Climacoceratidae|climacoceratids]]. Giraffids spread into Europe and Asia by the middle Miocene in a first [[Radiation (biology)|radiation]]. Another radiation began in the [[Pliocene]], but was terminated by a decline in diversity in the [[Pleistocene]].<ref name=finlayson>{{cite book|last1=Finlayson|first1=Clive|title=Neanderthals and Modern Humans : An Ecological and Evolutionary Perspective|date=2009|publisher=Cambridge University Press|location=Cambridge|isbn=978-0521121002|page=25|edition=Digitally printed}}</ref> Several important primitive giraffids existed more or less contemporaneously in the Miocene (23–10 million years ago), including ''[[Canthumeryx]]'', ''[[Giraffokeryx]]'', ''[[Palaeotragus]]'', and ''[[Samotherium]]''. According to palaeontologist and author Kathleen Hunt, ''Samotherium'' split into ''Okapia'' (18 million years ago) and ''Giraffa'' (12 million years ago).<ref>{{cite web|author=Hunt, Kathleen|title=Transitional Vertebrate Fossils FAQ Part 2C|publisher=TalkOrigins|url=http://www.talkorigins.org/faqs/faq-transitional/part2c.html#arti|access-date=28 April 2015}}</ref> However, J. D. Skinner argued that ''Canthumeryx'' gave rise to the okapi and giraffe through the latter three genera and that the okapi is the extant form of ''Palaeotragus''.<ref>{{cite journal |last1=Mitchell |first1=G. |last2=Skinner |first2=J. D. |title=On the origin, evolution and phylogeny of giraffes Giraffa camelopardalis |journal=Transactions of the Royal Society of South Africa |volume=58 |issue=1 |year=2003 |doi=10.1080/00359190309519935 |pages=51–73|s2cid=6522531 }}</ref> The okapi is sometimes referred to as a [[living fossil]], as it has existed as a species over a long geological time period, and morphologically resembles more primitive forms (e.g. ''Samotherium'').<ref name=prothero/><ref name="auto1">{{cite news |url=https://news.google.com/newspapers?nid=1499&dat=19570624&id=wAMkAAAAIBAJ&pg=6731,2170969 |title=Why Is the Okapi Called a Living Fossil |newspaper=The Milwaukee Journal |date=24 June 1954}}</ref>
The earliest members of the Giraffidae first appeared in the early [[Miocene]] in Africa, having diverged from the superficially deer-like [[Climacoceratidae|climacoceratids]]. Giraffids spread into Europe and Asia by the middle Miocene in a first [[Radiation (biology)|radiation]]. Another radiation began in the [[Pliocene]], but was terminated by a decline in diversity in the [[Pleistocene]].<ref name=finlayson>{{cite book|last1=Finlayson|first1=Clive|title=Neanderthals and Modern Humans : An Ecological and Evolutionary Perspective|date=2009|publisher=Cambridge University Press|location=Cambridge|isbn=978-0521121002|page=25|edition=Digitally printed}}</ref> Several important primitive giraffids existed more or less contemporaneously in the Miocene (23–10 million years ago), including ''[[Canthumeryx]]'', ''[[Giraffokeryx]]'', ''[[Palaeotragus]]'', and ''[[Samotherium]]''. According to palaeontologist and author Kathleen Hunt, ''Samotherium'' split into ''Okapia'' (18 million years ago) and ''Giraffa'' (12 million years ago).<ref>{{cite web|author=Hunt, Kathleen|title=Transitional Vertebrate Fossils FAQ Part 2C|publisher=TalkOrigins|url=http://www.talkorigins.org/faqs/faq-transitional/part2c.html#arti|access-date=28 April 2015}}</ref> However, J. D. Skinner argued that ''Canthumeryx'' gave rise to the okapi and giraffe through the latter three genera and that the okapi is the extant form of ''Palaeotragus''.<ref>{{cite journal |last1=Mitchell |first1=G. |last2=Skinner |first2=J. D. |title=On the origin, evolution and phylogeny of giraffes Giraffa camelopardalis |journal=Transactions of the Royal Society of South Africa |volume=58 |issue=1 |year=2003 |doi=10.1080/00359190309519935 |pages=51–73|bibcode=2003TRSSA..58...51M |s2cid=6522531 }}</ref> The okapi is sometimes referred to as a [[living fossil]], as it has existed as a species over a long geological time period, and morphologically resembles more primitive forms (e.g. ''Samotherium'').<ref name=prothero/><ref name="auto1">{{cite news |url=https://news.google.com/newspapers?nid=1499&dat=19570624&id=wAMkAAAAIBAJ&pg=6731,2170969 |title=Why Is the Okapi Called a Living Fossil |newspaper=The Milwaukee Journal |date=24 June 1954 }}{{Dead link|date=April 2023 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>


In 2016, a genetic study found that the common ancestor of giraffe and okapi lived about 11.5&nbsp;million years ago.<ref>{{cite journal |last1=Agaba |first1=M. |last2=Ishengoma |first2=E. |last3=Miller |first3=W. C. |last4=McGrath |first4=B. C. |last5=Hudson |first5=C. N. |last6=Bedoya Reina |first6=O. C. |last7=Ratan |first7=A. |last8=Burhans |first8=R. |last9=Chikhi |first9=R. |last10=Medvedev |first10=P. |last11=Praul |first11=C. A. |last12=Wu-Cavener |first12=L. |last13=Wood |first13=B. |last14=Robertson |first14=H. |last15=Penfold |first15=L. |last16=Cavener |first16=D. R. |title=Giraffe genome sequence reveals clues to its unique morphology and physiology |journal=[[Nature (journal)|Nature]] |date=May 2016 |volume=7 |pages=11519 |doi=10.1038/ncomms11519 |doi-access=free |pmid=27187213 |pmc=4873664|bibcode=2016NatCo...711519A }}</ref>
In 2016, a genetic study found that the common ancestor of giraffe and okapi lived about 11.5&nbsp;million years ago.<ref>{{cite journal |last1=Agaba |first1=M. |last2=Ishengoma |first2=E. |last3=Miller |first3=W. C. |last4=McGrath |first4=B. C. |last5=Hudson |first5=C. N. |last6=Bedoya Reina |first6=O. C. |last7=Ratan |first7=A. |last8=Burhans |first8=R. |last9=Chikhi |first9=R. |last10=Medvedev |first10=P. |last11=Praul |first11=C. A. |last12=Wu-Cavener |first12=L. |last13=Wood |first13=B. |last14=Robertson |first14=H. |last15=Penfold |first15=L. |last16=Cavener |first16=D. R. |title=Giraffe genome sequence reveals clues to its unique morphology and physiology |journal=[[Nature (journal)|Nature]] |date=May 2016 |volume=7 |pages=11519 |doi=10.1038/ncomms11519 |doi-access=free |pmid=27187213 |pmc=4873664|bibcode=2016NatCo...711519A }}</ref>


==Characteristics==
==Description==
[[File:Okapi (Okapia johnstoni) 2009-04-04 04.jpg|upright|left|thumbnail|Male okapi displaying his striking horizontal stripes]]
[[File:Okapi (Okapia johnstoni) 2009-04-04 04.jpg|upright|left|thumbnail|Male okapi displaying his striking horizontal stripes]]
The okapi is a medium-sized giraffid, standing {{convert|1.5|m|ftin|abbr=on}} tall at the shoulder. Its average body length is about {{convert|2.5|m|ftin|abbr=on}} and its weight ranges from {{Convert|200|to|350|kg|lb|abbr=on}}.<ref name="Burnie">{{cite book|author1=Burnie|author2=Don E. Wilson|name-list-style=amp|title=Animal|date=2001|publisher=DK|location=New York|isbn=0789477645|edition=1st American}}</ref> It has a long neck, and large and flexible ears. In sharp contrast to the white horizontal stripes on the legs and white ankles, the okapi's coat is a chocolate to reddish brown. The distinctive stripes resemble those of a zebra.<ref name=adw/> These features serve as an effective camouflage amidst dense vegetation. The face, throat, and chest are greyish white. [[Interdigital gland]]s are present on all four feet, and are slightly larger on the front feet.<ref name=bodmer>{{cite journal |last1=Bodmer |first1=R. E. |last2=Rabb |first2=G. B. |title=''Okapia johnstoni'' |journal=Mammalian Species |date=10 December 1992 |issue=422 |pages=1–8 |url=http://www.science.smith.edu/msi/pdf/i0076-3519-422-01-0001.pdf |doi=10.2307/3504153 |jstor=3504153 |url-status=dead |archive-url=https://web.archive.org/web/20150924122153/http://www.science.smith.edu/msi/pdf/i0076-3519-422-01-0001.pdf |archive-date=24 September 2015 }}</ref> Male okapis have short, hair-covered horn-like structures called [[ossicone]]s, less than {{convert|15|cm|in|abbr=on}} in length, which are similar in form and function to the ossicones of a [[giraffe]].<ref>{{cite journal|last1=Nasoori|first1=Alireza|date=2020|title=Formation, structure, and function of extra‐skeletal bones in mammals|url=https://archive.org/details/formation-structure-and-function-of-extra-skeletal-bones-in-mammals|journal=Biological Reviews|volume=95|issue=4|pages=986–1019|doi=10.1111/brv.12597|pmid=32338826|s2cid=216556342}}</ref> The okapi exhibits [[sexual dimorphism]], with females {{convert|4.2|cm|in|abbr=on}} taller on average, slightly redder, and lacking prominent ossicones, instead possessing [[hair whorl]]s.<ref name=grzimek>{{cite book |last1=Grzimek |first1=B. |title=Grzimek's Encyclopedia of Mammals (Volume 5) |date=1990 |publisher=McGraw-Hill Publishing Company |location=New York }}</ref><ref name=jstor>{{cite journal |last1=Solounias |first1=N. |title=Prevalence of ossicones in Giraffidae (Artiodactyla, Mammalia) |journal=Journal of Mammalogy |date=November 1988 |volume=69 |issue=4 |pages=845–8 |doi=10.2307/1381645 |jstor=1381645}}</ref>
The okapi is a medium-sized giraffid, standing {{convert|1.5|m|ftin|abbr=on}} tall at the shoulder. Its average body length is about {{convert|2.5|m|ftin|abbr=on}} and its weight ranges from {{Convert|200|to|350|kg|lb|abbr=on}}.<ref name="Burnie">{{cite book|author1=Burnie|author2=Don E. Wilson|name-list-style=amp|title=Animal|date=2001|publisher=DK|location=New York|isbn=0789477645|edition=1st American}}</ref> It has a long neck, and large and flexible ears. In sharp contrast to the white horizontal stripes on the legs and white ankles, the okapi's coat is a chocolate to reddish brown. The distinctive stripes resemble those of a zebra.<ref name=adw/> These features serve as an effective camouflage amidst dense vegetation. The face, throat, and chest are greyish white. [[Interdigital gland]]s are present on all four feet, and are slightly larger on the front feet.<ref name=bodmer>{{cite journal |last1=Bodmer |first1=R. E. |last2=Rabb |first2=G. B. |title=''Okapia johnstoni'' |journal=Mammalian Species |date=10 December 1992 |issue=422 |pages=1–8 |url=http://www.science.smith.edu/msi/pdf/i0076-3519-422-01-0001.pdf |doi=10.2307/3504153 |jstor=3504153 |s2cid=253915266 |url-status=dead |archive-url=https://web.archive.org/web/20150924122153/http://www.science.smith.edu/msi/pdf/i0076-3519-422-01-0001.pdf |archive-date=24 September 2015 |accessdate=17 April 2015 }}</ref> Male okapis have short, hair-covered horn-like structures called [[ossicone]]s, less than {{convert|15|cm|in|abbr=on}} in length, which are similar in form and function to the ossicones of a [[giraffe]].<ref>{{cite journal|last1=Nasoori|first1=Alireza|date=2020|title=Formation, structure, and function of extra-skeletal bones in mammals|url=https://archive.org/details/formation-structure-and-function-of-extra-skeletal-bones-in-mammals|journal=Biological Reviews|volume=95|issue=4|pages=986–1019|doi=10.1111/brv.12597|pmid=32338826|s2cid=216556342}}</ref> The okapi exhibits [[sexual dimorphism]], with females {{convert|4.2|cm|in|abbr=on}} taller on average, slightly redder, and lacking prominent ossicones, instead possessing [[hair whorl]]s.<ref name=grzimek>{{cite book |last1=Grzimek |first1=B. |title=Grzimek's Encyclopedia of Mammals (Volume 5) |date=1990 |publisher=McGraw-Hill Publishing Company |location=New York }}</ref><ref name=jstor>{{cite journal |last1=Solounias |first1=N. |title=Prevalence of ossicones in Giraffidae (Artiodactyla, Mammalia) |journal=Journal of Mammalogy |date=November 1988 |volume=69 |issue=4 |pages=845–8 |doi=10.2307/1381645 |jstor=1381645}}</ref>


The okapi shows several adaptations to its tropical habitat. The large number of [[rod cell]]s in the retina facilitate [[night vision]], and an efficient [[olfactory system]] is present. The large [[auditory bullae]] of the temporal bone allow a strong sense of hearing. The [[dental formula]] of the okapi is {{DentalFormula|upper=0.0.3.3|lower=3.1.3.3}}.<ref name=bodmer/> Teeth are low-[[crown (dentistry)|crowned]] and finely [[cusp (anatomy)|cusped]], and efficiently cut tender foliage. The large [[Large intestine|cecum and colon]] help in microbial digestion, and a quick rate of food passage allows for lower cell wall digestion than in other [[ruminant]]s.<ref name=kingdon/>
The okapi shows several adaptations to its tropical habitat. The large number of [[rod cell]]s in the retina facilitate [[night vision]], and an efficient [[olfactory system]] is present. The large [[auditory bullae]] of the temporal bone allow a strong sense of hearing. The [[dental formula]] of the okapi is {{DentalFormula|upper=0.0.3.3|lower=3.1.3.3}}.<ref name=bodmer/> Teeth are low-[[crown (dentistry)|crowned]] and finely [[cusp (anatomy)|cusped]], and efficiently cut tender foliage. The large [[Large intestine|cecum and colon]] help in microbial digestion, and a quick rate of food passage allows for lower cell wall digestion than in other [[ruminant]]s.<ref name=kingdon/>
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===Diet===
===Diet===
[[File:Okapi tongue.jpg|thumbnail|left|The long tongue of the okapi]]
[[File:Okapi tongue.jpg|thumbnail|left|The long tongue of the okapi]]
Okapis are [[herbivore]]s, feeding on tree leaves and buds, [[Poaceae|grasses]], [[fern]]s, fruits, and [[fungus|fungi]]. They are unique in the Ituri Forest as they are the only known mammal that feeds solely on understory vegetation, where they use their {{convert|18|in|cm|adj=mid|-long}} tongues to selectively browse for suitable plants. The tongue is also used to groom their ears and eyes.<ref>{{Cite web|url=http://www.giraffidsg.org/files/2016/02/Okapi-conservation-strategy-2015-2025-final-EN1.pdf|title=Okapi Conservation Strategy and Status Review|date=2018-02-21|website=www.giraffidsg.org|access-date=2018-02-21|archive-url=https://web.archive.org/web/20180221222436/http://www.giraffidsg.org/files/2016/02/Okapi-conservation-strategy-2015-2025-final-EN1.pdf|archive-date=21 February 2018|url-status=dead}}</ref> They prefer to feed in [[treefall gap]]s. The okapi has been known to feed on over 100 species of plants, some of which are known to be poisonous to humans and other animals. Fecal analysis shows that none of those 100 species dominates the diet of the okapi. Staple foods comprise [[shrub]]s and [[liana]]s. The main constituents of the diet are woody, [[dicot]]yledonous species; [[monocot]]yledonous plants are not eaten regularly. In the Ituri forest, the okapi feeds mainly upon the plant families [[Acanthaceae]], [[Ebenaceae]], [[Euphorbiaceae]], [[Flacourtiaceae]], [[Loganiaceae]], [[Rubiaceae]], and [[Violaceae]].<ref name=bodmer/><ref name=hart/>
Okapis are [[herbivore]]s, feeding on tree leaves and buds, [[branch]]es, [[Poaceae|grasses]], [[fern]]s, fruits, and [[fungus|fungi]].<ref>{{cite web | url=https://animaldiversity.org/accounts/Okapia_johnstoni/ | title=Okapia johnstoni (Okapi) | website=[[Animal Diversity Web]] }}</ref> They are unique in the Ituri Forest as they are the only known mammal that feeds solely on understory vegetation, where they use their {{convert|18|in|cm|adj=mid|-long}} tongues to selectively browse for suitable plants. The tongue is also used to groom their ears and eyes.<ref>{{Cite web|url=http://www.giraffidsg.org/files/2016/02/Okapi-conservation-strategy-2015-2025-final-EN1.pdf|title=Okapi Conservation Strategy and Status Review|date=2018-02-21|website=www.giraffidsg.org|access-date=2018-02-21|archive-url=https://web.archive.org/web/20180221222436/http://www.giraffidsg.org/files/2016/02/Okapi-conservation-strategy-2015-2025-final-EN1.pdf|archive-date=21 February 2018|url-status=dead}}</ref> They prefer to feed in [[treefall gap]]s. The okapi has been known to feed on over 100 species of plants, some of which are known to be poisonous to humans and other animals. Fecal analysis shows that none of those 100 species dominates the diet of the okapi. Staple foods comprise [[shrub]]s and [[liana]]s. The main constituents of the diet are woody, [[dicot]]yledonous species; [[monocot]]yledonous plants are not eaten regularly. In the Ituri forest, the okapi feeds mainly upon the plant families [[Acanthaceae]], [[Ebenaceae]], [[Euphorbiaceae]], [[Flacourtiaceae]], [[Loganiaceae]], [[Rubiaceae]], and [[Violaceae]].<ref name=bodmer/><ref name=hart/>


===Reproduction===
===Reproduction===
[[File:Okapi and calf at White Oak.jpg |thumbnail|A female okapi with her calf at White Oak Conservation]]
[[File:Okapi and calf at White Oak.jpg |thumbnail|A female okapi with her calf at White Oak Conservation]]
Female okapis become sexually mature at about one-and-a-half years old, while males reach maturity after two years. [[Rut (mammalian reproduction)|Rut]] in males and [[estrous]] in females does not depend on the season. In captivity, estrous cycles recur every 15&nbsp;days.<ref name=kingdon/><ref name=reproduction>{{cite journal |last1=Schwarzenberger |first1=F. |last2=Rietschel |first2=W. |last3=Matern |first3=B. |last4=Schaftenaar |first4=W. |last5=Bircher |first5=P. |last6=van Puijenbroeck |first6=B. |last7=Leus |first7=K. |title=Noninvasive reproductive monitoring in the okapi (''Okapia johnstoni'') |journal=Journal of Zoo and Wildlife Medicine |publisher=The American Association of Zoo Veterinarians |date=December 1999 |volume=30 |issue=4 |pages=497–503 |pmid=10749434}}</ref> The male and the female begin courtship by circling, smelling, and licking each other. The male shows his interest by extending his neck, tossing his head, and protruding one leg forward. This is followed by mounting and copulation.<ref name=grzimek/>
Female okapis become [[sexual maturity|sexually mature]] at about one-and-a-half years old, while males reach maturity after two years. [[Rut (mammalian reproduction)|Rut]] in males and [[estrus]] in females does not depend on the season. In captivity, estrous cycles recur every 15&nbsp;days.<ref name=kingdon/><ref name=reproduction>{{cite journal |last1=Schwarzenberger |first1=F. |last2=Rietschel |first2=W. |last3=Matern |first3=B. |last4=Schaftenaar |first4=W. |last5=Bircher |first5=P. |last6=van Puijenbroeck |first6=B. |last7=Leus |first7=K. |title=Noninvasive reproductive monitoring in the okapi (''Okapia johnstoni'') |journal=Journal of Zoo and Wildlife Medicine |publisher=The American Association of Zoo Veterinarians |date=December 1999 |volume=30 |issue=4 |pages=497–503 |pmid=10749434}}</ref> The male and the female begin [[courtship display|courtship]] by circling, smelling, and licking each other. The male shows his interest by extending his neck, tossing his head, and protruding one leg forward. This is followed by mounting and [[copulation (zoology)|copulation]].<ref name=grzimek/>


The [[gestational period]] is around 440 to 450&nbsp;days long, following which usually a single calf is born, weighing {{convert|14|-|30|kg|lb|abbr=on}}. The [[udder]] of the pregnant female starts swelling 2&nbsp;months before [[parturition]], and [[vulva]]l discharges may occur. Parturition takes 3–4&nbsp;hours, and the female stands throughout this period, though she may rest during brief intervals. The mother consumes the afterbirth and extensively grooms the infant. Her milk is very rich in proteins and low in fat.<ref name=kingdon/>
The [[gestational period]] is around 440 to 450&nbsp;days long, following which usually a single calf is born, weighing {{convert|14|-|30|kg|lb|abbr=on}}. The [[udder]] of the pregnant female starts swelling 2&nbsp;months before [[parturition]], and [[vulva]]l discharges may occur. Parturition takes 3–4&nbsp;hours, and the female stands throughout this period, though she may rest during brief intervals. The mother consumes the afterbirth and extensively grooms the infant. Her milk is very rich in proteins and low in fat.<ref name=kingdon/>


As in other ruminants, the infant can stand within 30&nbsp;minutes of birth. Although generally similar to adults, newborn calves have long hairs around the eye (resembling false eyelashes), a long dorsal [[Mane (horse)|mane]], and long white hairs in the stripes.<ref>{{cite web |last1=Jirik |first1=Kate |title=Okapia johnstoni Fact Sheet |url=https://ielc.libguides.com/sdzg/factsheets/okapi/characteristics |website=ielc.libguides.com |publisher=[[San Diego Zoo Wildlife Alliance]] |access-date=28 August 2021 |language=en}}</ref> These features gradually disappear and give way to the general appearance within a year. The juveniles are kept in hiding, and nursing takes place infrequently. Calves are known not to defecate for the first month or two of life, which is hypothesized to help avoid predator detection in their most vulnerable phase of life.<ref>{{Cite web|url=https://www.diergaardeblijdorp.nl/en/2019/09/02/rare-okapi-born/|title=Rare okapi born in Rotterdam Zoo|date=2019-09-02|website=Rotterdam Zoo|language=en-US|access-date=2020-02-20}}</ref> The growth rate of calves is appreciably high in the first few months of life, after which it gradually declines. Juveniles start taking solid food from 3&nbsp;months, and weaning takes place at 6&nbsp;months. Ossicone development in males takes 1&nbsp;year after birth. The okapi's typical lifespan is 20–30&nbsp;years.<ref name=bodmer/>
As in other ruminants, the infant can stand within 30&nbsp;minutes of birth. Although generally similar to adults, newborn calves have long hairs around the eye (resembling false eyelashes), a long dorsal [[Mane (horse)|mane]], and long white hairs in the stripes.<ref>{{cite web |last1=Jirik |first1=Kate |title=Okapia johnstoni Fact Sheet |url=https://ielc.libguides.com/sdzg/factsheets/okapi/characteristics |website=ielc.libguides.com |publisher=[[San Diego Zoo Wildlife Alliance]] |access-date=28 August 2021 |language=en}}</ref> These features gradually disappear and give way to the general appearance within a year. The juveniles are kept in hiding, and nursing takes place infrequently. Calves are known not to defecate for the first month or two of life, which is hypothesized to help avoid predator detection in their most vulnerable phase of life.<ref>{{Cite web|url=https://www.diergaardeblijdorp.nl/en/2019/09/02/rare-okapi-born/|title=Rare okapi born in Rotterdam Zoo|date=2019-09-02|website=Rotterdam Zoo|language=en-US|access-date=2020-02-20|archive-date=20 February 2020|archive-url=https://web.archive.org/web/20200220145536/https://www.diergaardeblijdorp.nl/en/2019/09/02/rare-okapi-born/|url-status=dead}}</ref> The growth rate of calves is appreciably high in the first few months of life, after which it gradually declines. Juveniles start taking solid food from 3&nbsp;months, and weaning takes place at 6&nbsp;months. Ossicone development in males takes 1&nbsp;year after birth. The okapi's typical lifespan is 20–30&nbsp;years.<ref name=bodmer/>


==Distribution and habitat==
==Distribution and habitat==
The okapi is [[endemic]] to the Democratic Republic of the Congo, where it occurs north and east of the [[Congo River]]. It ranges from the [[Maiko National Park]] northward to the [[Ituri rainforest]], then through the river basins of the Rubi, [[Lake Tele]], and [[Ebola River|Ebola]] to the west and the [[Ubangi River]] further north. Smaller populations exist west and south of the Congo River. It is also common in the [[Wamba, Luo Reserve|Wamba]] and Epulu areas. It is extinct in [[Uganda]].<ref name="iucn status 19 November 2021" />
The okapi is [[endemic]] to the Democratic Republic of the Congo, where it occurs north and east of the [[Congo River]]. It ranges from the [[Maiko National Park]] northward to the [[Ituri rainforest]], then through the river basins of the Rubi, [[Lake Tele]], and [[Ebola River|Ebola]] to the west and the [[Ubangi River]] further north. Smaller populations exist west and south of the Congo River. It is also common in the [[Wamba, Luo Reserve|Wamba]] and Epulu areas. It is extinct in [[Uganda]].<ref name="iucn status 19 November 2021" />


The okapi inhabits [[canopy (biology)|canopy]] forests at altitudes of {{convert|500|-|1500|m|ft|abbr=on}}. It occasionally uses seasonally inundated areas, but does not occur in [[gallery forest]]s, [[swamp forest]]s, and habitats disturbed by [[human settlement]]s. In the wet season, it visits rocky [[inselbergs]] that offer forage uncommon elsewhere. Results of research conducted in the late 1980s in a mixed ''[[Cynometra]]'' forest indicated that the okapi population density averaged 0.53 animals per square kilometre.<ref name=hart>{{cite journal |last1=Hart |first1=J. A. |last2=Hart |first2=T. B. |title=Ranging and feeding behaviour of okapi (''Okapia johnstoni'') in the Ituri Forest of Zaire: food limitation in a rain-forest herbivore |journal=Symposium of the Zoological Society of London |date=1989 |volume=61 |pages=31–50}}</ref> In 2008, it was recorded in [[Virunga National Park]].<ref>{{cite book |author1=Nixon, S. C. |author2=Lusenge, T. |year=2008 |title=Conservation status of okapi in Virunga National Park, Democratic Republic of Congo. ZSL Conservation Report No. 9 |publisher=The Zoological Society of London |location=London |url=https://www.zsl.org/sites/default/files/Nixon%20and%20Lusenge%202008%20-%20Conservation%20status%20of%20okapi%20in%20Virunga%20National%20Park%2C%20DRC.pdf}}</ref> There is also evidence that okapis were also observed in the [[Semuliki National Park|Semuliki Valley]] in [[Uganda]] by Europeans, but later became extinct in the late 1970s.<ref>{{cite journal |last1=Sever |first1=Zvi |title=Searching for the okapi (Okapia johnstoni) in Semuliki National Park, Uganda |journal=African Journal of Ecology |date=3 October 2020 |volume=59 |issue=1 |pages=286–292 |doi=10.1111/aje.12796 |s2cid=224839859 |url=https://onlinelibrary.wiley.com/doi/abs/10.1111/aje.12796 |access-date=26 March 2021}}</ref> The Semuliki Valley provides a similar habitat to the [[Congo Basin]].
The okapi inhabits [[canopy (biology)|canopy]] forests at elevations of {{convert|500|-|1500|m|ft|abbr=on}}. It occasionally uses seasonally inundated areas, but does not occur in [[gallery forest]]s, [[swamp forest]]s, and habitats disturbed by [[human settlement]]s. In the wet season, it visits rocky [[inselbergs]] that offer forage uncommon elsewhere. Results of research conducted in the late 1980s in a mixed ''[[Cynometra]]'' forest indicated that the okapi population density averaged 0.53 animals per square kilometre.<ref name=hart>{{cite journal |last1=Hart |first1=J. A. |last2=Hart |first2=T. B. |title=Ranging and feeding behaviour of okapi (''Okapia johnstoni'') in the Ituri Forest of Zaire: food limitation in a rain-forest herbivore |journal=Symposium of the Zoological Society of London |date=1989 |volume=61 |pages=31–50}}</ref> In 2008, it was recorded in [[Virunga National Park]].<ref>{{cite book |author1=Nixon, S. C. |author2=Lusenge, T. |year=2008 |title=Conservation status of okapi in Virunga National Park, Democratic Republic of Congo. ZSL Conservation Report No. 9 |publisher=The Zoological Society of London |location=London |url=https://www.zsl.org/sites/default/files/Nixon%20and%20Lusenge%202008%20-%20Conservation%20status%20of%20okapi%20in%20Virunga%20National%20Park%2C%20DRC.pdf |access-date=22 November 2018 |archive-date=25 August 2021 |archive-url=https://web.archive.org/web/20210825193426/https://www.zsl.org/sites/default/files/Nixon%20and%20Lusenge%202008%20-%20Conservation%20status%20of%20okapi%20in%20Virunga%20National%20Park%2C%20DRC.pdf |url-status=dead }}</ref> There is also evidence that okapis were also observed in the [[Semuliki National Park|Semuliki Valley]] in [[Uganda]] by Europeans, but later became extinct in the late 1970s.<ref>{{cite journal |last1=Sever |first1=Zvi |title=Searching for the okapi (Okapia johnstoni) in Semuliki National Park, Uganda |journal=African Journal of Ecology |date=3 October 2020 |volume=59 |issue=1 |pages=286–292 |doi=10.1111/aje.12796 |s2cid=224839859 |url=https://onlinelibrary.wiley.com/doi/abs/10.1111/aje.12796 |access-date=26 March 2021}}</ref> The Semuliki Valley provides a similar habitat to the [[Congo Basin]].


==Status==
==Status==
===Threats and conservation===
===Threats and conservation===
[[File:Okapi2.jpg|thumb|left|Okapi at [[Disney's Animal Kingdom]]]]
[[File:Okapi2.jpg|thumb|left|Okapi at [[Disney's Animal Kingdom]]]]
The IUCN classifies the okapi as endangered.<ref name=OCP>{{cite news |last=Hebert |first=Amanda |date=26 November 2013 |title=Okapi Added to IUCN'S Endangered Species List |url=http://www.epulu-story.org/assets/endangered-press-release-11.25.docx |location=[[Jacksonville, Florida]] |publisher=[[Okapi Conservation Project]] |access-date=3 June 2014}}</ref> It is fully protected under Congolese law. The [[Okapi Wildlife Reserve]] and [[Maiko National Park]] support significant populations of the okapi, though a steady decline in numbers has occurred due to several threats. Other areas of occurrence are the [[Rubi Tele Hunting Reserve]] and the Abumombanzi Reserve. Major threats include habitat loss due to [[logging]] and human settlement. Extensive hunting for [[bushmeat]] and skin and illegal mining have also led to population declines. A threat that has emerged quite recently is the presence of illegal armed groups around protected areas, inhibiting conservation and monitoring actions. A small population occurs north of the [[Virunga National Park]], but lacks protection due to the presence of armed groups in the vicinity.<ref name="iucn status 19 November 2021" /> In June 2012, a gang of poachers attacked the headquarters of the [[Okapi Wildlife Reserve]], killing six guards and other staff<ref>{{cite news|last1=Flocken|first1=J.|title=Tragic Losses in the Heart of Darkness|url=http://www.huffingtonpost.com/jeffrey-flocken/okapi-wildlife-reserve-attack_b_1634403.html|access-date=18 April 2015|agency=HuffPost|date=29 June 2012}}</ref> as well as all 14 okapis at their breeding center.<ref>{{cite news|last1=Jones|first1=P.|title=Infamous elephant poacher turns cannibal in the Congo|url=https://news.mongabay.com/2013/04/infamous-elephant-poacher-turns-cannibal-in-the-congo/|access-date=16 July 2017|agency=Mongabay|date=3 April 2013}}</ref>
The IUCN classifies the okapi as endangered.<ref name=OCP>{{cite news |last=Hebert |first=Amanda |date=26 November 2013 |title=Okapi Added to IUCN'S Endangered Species List |url=http://www.epulu-story.org/assets/endangered-press-release-11.25.docx |location=[[Jacksonville, Florida]] |publisher=[[Okapi Conservation Project]] |access-date=3 June 2014}}</ref> It is fully protected under Congolese law. The [[Okapi Wildlife Reserve]] and [[Maiko National Park]] support significant populations of the okapi, though a steady decline in numbers has occurred due to several threats. Other areas of occurrence are the [[Rubi Tele Hunting Reserve]] ,the Abumombanzi Reserve,the
[[Sankuru Nature Reserve]], the [[Lomami National Park]]. Major threats include habitat loss due to [[logging]] and human settlement. Extensive hunting for [[bushmeat]] and skin and illegal mining have also led to population declines. A threat that has emerged quite recently is the presence of illegal armed groups around protected areas, inhibiting conservation and monitoring actions. A small population occurs north of the [[Virunga National Park]], but lacks protection due to the presence of armed groups in the vicinity.<ref name="iucn status 19 November 2021" /> In June 2012, a gang of poachers attacked the headquarters of the [[Okapi Wildlife Reserve]], killing six guards and other staff<ref>{{cite news|last1=Flocken|first1=J.|title=Tragic Losses in the Heart of Darkness|url=http://www.huffingtonpost.com/jeffrey-flocken/okapi-wildlife-reserve-attack_b_1634403.html|access-date=18 April 2015|agency=HuffPost|date=29 June 2012}}</ref> as well as all 14 okapis at their breeding center.<ref>{{cite news|last1=Jones|first1=P.|title=Infamous elephant poacher turns cannibal in the Congo|url=https://news.mongabay.com/2013/04/infamous-elephant-poacher-turns-cannibal-in-the-congo/|access-date=16 July 2017|agency=Mongabay|date=3 April 2013}}</ref>


The [[Okapi Conservation Project]], established in 1987, works towards the conservation of the okapi, as well as the growth of the indigenous [[Mbuti people]].<ref name="iucn status 19 November 2021" /> In November 2011, the [[White Oak Conservation]] center and [[Jacksonville Zoo and Gardens]] hosted an international meeting of the Okapi [[Species Survival Plan]] and the Okapi [[European Endangered Species Programme]] at [[Jacksonville]], which was attended by representatives from zoos from the US, Europe, and Japan. The aim was to discuss the management of captive okapis and arrange support for okapi conservation. Many zoos in North America and Europe currently have okapis in captivity.<ref name=meet>{{cite web|title=Okapi SSP and EEP International Meeting|url=http://www.okapiconservation.org/ssp-eep/|website=Okapi Conservation Project|publisher=Wildlife Conservation Global|access-date=18 April 2015}}</ref>
The [[Okapi Conservation Project]], established in 1987, works towards the conservation of the okapi, as well as the growth of the indigenous [[Mbuti people]].<ref name="iucn status 19 November 2021" /> In November 2011, the [[White Oak Conservation]] center and [[Jacksonville Zoo and Gardens]] hosted an international meeting of the Okapi [[Species Survival Plan]] and the Okapi [[European Endangered Species Programme]] at [[Jacksonville]], which was attended by representatives from zoos from the US, Europe, and Japan. The aim was to discuss the management of captive okapis and arrange support for okapi conservation. Many zoos in North America and Europe currently have okapis in captivity.<ref name=meet>{{cite web|title=Okapi SSP and EEP International Meeting|url=http://www.okapiconservation.org/ssp-eep/|website=Okapi Conservation Project|publisher=Wildlife Conservation Global|access-date=18 April 2015|archive-date=18 April 2015|archive-url=https://web.archive.org/web/20150418101547/http://www.okapiconservation.org/ssp-eep/|url-status=dead}}</ref>


===Okapis in zoos===
===Okapis in zoos===
[[File:Jonge dieren in onze dierentuinen, Blijdorp Weeknummer 60-17 - Open Beelden - 47662.ogv|thumb|thumbtime=0:09|1960 Dutch newsreel about okapis in [[Diergaarde Blijdorp]]]]
[[File:Jonge dieren in onze dierentuinen, Blijdorp Weeknummer 60-17 - Open Beelden - 47662.ogv|thumb|thumbtime=0:09|1960 Dutch newsreel about okapis in [[Diergaarde Blijdorp]]]]


Around 100 okapis are in accredited [[Association of Zoos and Aquariums]] (AZA) zoos. The okapi population is managed in America by the AZA's Species Survival Plan, a breeding program that works to ensure genetic diversity in the captive population of endangered animals, while the [[European Endangered Species Programme|EEP]] (European studbook) and ISB (Global studbook) are managed by [[Antwerp Zoo]] in Belgium, which was the first zoo to have an Okapi on display (in 1919), as well as one of the most successful in breeding them.<ref>{{cite web|url=http://www.flanderstoday.eu/living/okapis-and-men-antwerp-zoo-helps-preserve-endangered-species |title=Of okapis and men: Antwerp Zoo helps preserve endangered species |date=2016-08-12 |website=[[The Bulletin (Belgian magazine)#Flanders Today|Flanders Today]] |access-date=2018-05-27 |archive-url=https://web.archive.org/web/20160814194411/http://www.flanderstoday.eu/living/okapis-and-men-antwerp-zoo-helps-preserve-endangered-species |archive-date=2016-08-14 |url-status=dead}}</ref><ref>{{cite journal|url=https://www.eaza.net/assets/Uploads/Zooquaria/ZQ85.pdf |title=Okapi's Half-Century |journal=Zooquaria |publisher=[[European Association of Zoos and Aquaria|EAZA]] |issue=85 |date=Spring 2014 |page=7 |access-date=2021-02-23}}</ref>
Around 100 okapis are in accredited [[Association of Zoos and Aquariums]] (AZA) zoos. The okapi population is managed in America by the AZA's Species Survival Plan, a breeding program that works to ensure genetic diversity in the captive population of endangered animals, while the [[European Endangered Species Programme|EEP]] (European studbook) and ISB (Global studbook) are managed by [[Antwerp Zoo]] in Belgium, which was the first zoo to have an Okapi on display (in 1919), as well as one of the most successful in breeding them.<ref>{{cite web|url=http://www.flanderstoday.eu/living/okapis-and-men-antwerp-zoo-helps-preserve-endangered-species |title=Of okapis and men: Antwerp Zoo helps preserve endangered species |date=2016-08-12 |website=[[The Bulletin (Belgian magazine)#Flanders Today|Flanders Today]] |access-date=2018-05-27 |archive-url=https://web.archive.org/web/20160814194411/http://www.flanderstoday.eu/living/okapis-and-men-antwerp-zoo-helps-preserve-endangered-species |archive-date=2016-08-14 |url-status=dead}}</ref><ref>{{cite journal |url=https://www.eaza.net/assets/Uploads/Zooquaria/ZQ85.pdf |title=Okapi's Half-Century |journal=Zooquaria |publisher=[[European Association of Zoos and Aquaria|EAZA]] |issue=85 |date=Spring 2014 |page=7 |access-date=2021-02-23 |archive-date=25 August 2021 |archive-url=https://web.archive.org/web/20210825055536/https://www.eaza.net/assets/Uploads/Zooquaria/ZQ85.pdf |url-status=dead }}</ref>


In 1937, the [[Bronx Zoo]] became the first in North America to acquire an okapi.<ref>{{cite web|url=https://newsroom.wcs.org/News-Releases/articleType/ArticleView/articleId/4802/Bronx-Zoo-Debuts-Its-Baby-Okapi.aspx |title=Bronx Zoo Debuts Its Baby Okapi |date=2009-07-27 |work=[[Wildlife Conservation Society|WCSNewsroom]] |access-date=2018-10-19}}</ref> With one of the most successful breeding programs, 13 calves have been born there between 1991 and 2011.<ref>{{Cite web | url=https://newyork.cbslocal.com/2011/11/08/baby-okapi-makes-public-debut-at-bronx-zoo/ |title = Baby Okapi Makes Public Debut At Bronx Zoo|date = 8 November 2011 |website=[[WCBS-TV|newyork.cbslocal.com]] |access-date=2018-10-19}}</ref> The [[San Diego Zoo]] has exhibited okapis since 1956, and their first okapi calf was born in 1962.<ref name="SDZ">{{cite web|url=http://animals.sandiegozoo.org/animals/okapi |title=Animals & Plants {{!}} Okapi |website=[[San Diego Zoo|animals.sandiegozoo.org]] |access-date=2017-10-04}}</ref> Since then, there have been more than 60 okapis born at the zoo and the nearby [[San Diego Zoo Safari Park]], the most recent being Mosi, a male calf born on 21&nbsp;July 2017 at the zoo.<ref>{{cite web|url=https://www.sandiegouniontribune.com/entertainment/things-to-do/sd-me-zoo-okapi-20170823-story.html |title=Endangered okapi born at San Diego Zoo |last=Peterson |first=Karla |date=2017-08-23 |work=[[The San Diego Union-Tribune]] |access-date=2021-02-23}}</ref> The [[Brookfield Zoo]] in [[Chicago]] has also greatly contributed to the captive population of okapis in accredited zoos. The zoo has had 28 okapi births since 1959.<ref>{{cite web|url=https://chicago.cbslocal.com/2017/05/26/brookfield-zoo-okapi-birth/ |title=Brookfield Zoo Celebrates Its 28th Okapi Birth Since 1959 |date=26 May 2017 |website=[[WBBM-TV|chicago.cbslocal.com]] |access-date=2017-10-04}}</ref>
In 1937, the [[Bronx Zoo]] became the first in North America to acquire an okapi.<ref>{{cite web|url=https://newsroom.wcs.org/News-Releases/articleType/ArticleView/articleId/4802/Bronx-Zoo-Debuts-Its-Baby-Okapi.aspx |title=Bronx Zoo Debuts Its Baby Okapi |date=2009-07-27 |work=[[Wildlife Conservation Society|WCSNewsroom]] |access-date=2018-10-19}}</ref> With one of the most successful breeding programs, 13 calves have been born there between 1991 and 2011.<ref>{{Cite web | url=https://newyork.cbslocal.com/2011/11/08/baby-okapi-makes-public-debut-at-bronx-zoo/ |title = Baby Okapi Makes Public Debut At Bronx Zoo|date = 8 November 2011 |website=[[WCBS-TV|newyork.cbslocal.com]] |access-date=2018-10-19}}</ref> The [[San Diego Zoo]] has exhibited okapis since 1956, and their first okapi calf was born in 1962.<ref name="SDZ">{{cite web|url=http://animals.sandiegozoo.org/animals/okapi |title=Animals & Plants {{!}} Okapi |website=[[San Diego Zoo|animals.sandiegozoo.org]] |access-date=2017-10-04}}</ref> Since then, there have been more than 60 okapis born at the zoo and the nearby [[San Diego Zoo Safari Park]], the most recent being Mosi, a male calf born on 21&nbsp;July 2017 at the zoo.<ref>{{cite web|url=https://www.sandiegouniontribune.com/entertainment/things-to-do/sd-me-zoo-okapi-20170823-story.html |title=Endangered okapi born at San Diego Zoo |last=Peterson |first=Karla |date=2017-08-23 |work=[[The San Diego Union-Tribune]] |access-date=2021-02-23}}</ref> The [[Brookfield Zoo]] in [[Chicago]] has also greatly contributed to the captive population of okapis in accredited zoos. The zoo has had 28 okapi births since 1959.<ref>{{cite web|url=https://chicago.cbslocal.com/2017/05/26/brookfield-zoo-okapi-birth/ |title=Brookfield Zoo Celebrates Its 28th Okapi Birth Since 1959 |date=26 May 2017 |website=[[WBBM-TV|chicago.cbslocal.com]] |access-date=2017-10-04}}</ref>


Other North American zoos that exhibit and breed okapis include: [[Denver Zoo]] and [[Cheyenne Mountain Zoo]] (Colorado); [[Houston Zoo]], [[Dallas Zoo]], and [[San Antonio Zoo]] (Texas); [[Disney's Animal Kingdom]], [[White Oak Conservation]], [[Zoo Miami]], and [[ZooTampa at Lowry Park]] (Florida); [[Los Angeles Zoo]], [[Sacramento Zoo]], and [[San Diego Zoo]] (California); [[Saint Louis Zoo]] (Missouri); [[Cincinnati Zoo and Botanical Garden]] and [[Columbus Zoo and Aquarium]] (Ohio); [[Memphis Zoo]] and [[Nashville Zoo at Grassmere|Nashville Zoo]] (Tennessee); [[The Maryland Zoo in Baltimore]] (Maryland); [[Sedgwick County Zoo]] and [[Tanganyika Wildlife Park]] (Kansas); [[Roosevelt Park Zoo]]<ref>{{Cite news|date=15 September 2017|title=Okapi arrives at Roosevelt Park Zoo|work=Minot Daily News|url=https://www.minotdailynews.com/news/local-news/2017/09/okapi-arrives-at-roosevelt-park-zoo/|access-date=18 May 2020 |archive-url=https://web.archive.org/web/20200806033135/https://www.minotdailynews.com/news/local-news/2017/09/okapi-arrives-at-roosevelt-park-zoo/ |archive-date=2020-08-06 |url-status=live}}</ref> (North Dakota); [[Henry Doorly Zoo and Aquarium]] (Nebraska); [[Philadelphia Zoo]] (Pennsylvania); [[Potawatomi Zoo]]<ref>{{Cite web|url=https://www.potawatomizoo.org/animal/okapi/|title = Okapi}}</ref> (Indiana); [[Oklahoma City Zoo and Botanical Garden]] (Oklahoma); and [[Blank Park Zoo]] (Iowa).<ref>{{cite web|title=Okapi Conservation Project {{!}} The Americas |url=https://www.okapiconservation.org/zoo-network-the-americas/ |website=okapiconservation.org |access-date=2019-05-13}}</ref>
Other North American zoos that exhibit and breed okapis include: [[Denver Zoo]] and [[Cheyenne Mountain Zoo]] (Colorado); [[Houston Zoo]], [[Dallas Zoo]], and [[San Antonio Zoo]] (Texas); [[Disney's Animal Kingdom]], [[White Oak Conservation]], [[Zoo Miami]], and [[ZooTampa at Lowry Park]] (Florida); [[Los Angeles Zoo]], [[Sacramento Zoo]], and [[San Diego Zoo]] (California); [[Saint Louis Zoo]] (Missouri); [[Cincinnati Zoo and Botanical Garden]] and [[Columbus Zoo and Aquarium]] (Ohio); [[Memphis Zoo]] and [[Nashville Zoo at Grassmere|Nashville Zoo]] (Tennessee); [[The Maryland Zoo in Baltimore]] (Maryland); [[Sedgwick County Zoo]] and [[Tanganyika Wildlife Park]] (Kansas); [[Roosevelt Park Zoo]]<ref>{{Cite news|date=15 September 2017|title=Okapi arrives at Roosevelt Park Zoo|work=Minot Daily News|url=https://www.minotdailynews.com/news/local-news/2017/09/okapi-arrives-at-roosevelt-park-zoo/|access-date=18 May 2020 |archive-url=https://web.archive.org/web/20200806033135/https://www.minotdailynews.com/news/local-news/2017/09/okapi-arrives-at-roosevelt-park-zoo/ |archive-date=2020-08-06 |url-status=live}}</ref> (North Dakota); [[Henry Doorly Zoo and Aquarium]] (Nebraska); [[Philadelphia Zoo]] (Pennsylvania); [[Potawatomi Zoo]]<ref>{{Cite web|url=https://www.potawatomizoo.org/animal/okapi/|title = Okapi}}</ref> (Indiana); [[Oklahoma City Zoo and Botanical Garden]] (Oklahoma); [[Blank Park Zoo]] (Iowa);<ref>{{cite web |title=Okapi Conservation Project {{!}} The Americas |url=https://www.okapiconservation.org/zoo-network-the-americas/ |website=okapiconservation.org |access-date=2019-05-13 |archive-date=5 February 2021 |archive-url=https://web.archive.org/web/20210205130622/https://www.okapiconservation.org/zoo-network-the-americas/ |url-status=dead }}</ref> and [[Potter Park Zoo]] (Michigan).<ref>{{cite web |title=Potter Park Zoo Welcomes Elombe the Okapi |url=https://potterparkzoo.org/potter-park-zoo-welcomes-elombe-the-okapi/ |website=potterparkzoo.org |date=2024-05-07 |access-date=2024-09-25}}</ref>


In Europe, zoos that exhibit and breed okapis include: [[Chester Zoo]], [[London Zoo]], [[Marwell Zoo]], [[Wild Place Project|The Wild Place]],<ref>{{cite web|url=https://bristolzoo.org.uk/latest-zoo-news/helping-to-protect-endangered-species-around-the-world |title=Helping to protect endangered species around the world |date=2019-05-17 |work=Bristol Zoo |access-date=2021-02-23}}</ref> and [[Yorkshire Wildlife Park]]<ref>{{cite web|url=https://www.yorkshirewildlifepark.com/okapi-arrival/ |title=Rare Okapi Arrive at Yorkshire Wildlife Park |date=2018-05-17 |work=Yorkshire Wildlife Park |access-date=2021-02-23}}</ref> (United Kingdom); [[Dublin Zoo]] (Ireland); [[Berlin Zoo]], [[Frankfurt Zoological Garden|Frankfurt Zoo]], [[Wilhelma|Wilhelma Zoo]], [[Wuppertal Zoo]], [[Cologne Zoological Garden|Cologne Zoo]], and [[Leipzig Zoological Garden|Leipzig Zoo]] (Germany); [[Basel Zoo|Zoo Basel]] (Switzerland); [[Copenhagen Zoo]] (Denmark); [[Diergaarde Blijdorp|Rotterdam Zoo]] and [[Safaripark Beekse Bergen]] (Netherlands); [[Dvůr Králové Zoo]] (Czech Republic); [[Wrocław Zoo]] (Poland); [[Zoo de Doué|Bioparc Zoo de Doué]] and [[ZooParc de Beauval]] (France); and [[Lisbon Zoo]] (Portugal).<ref>{{cite web|title=Okapi Conservation Project {{!}} Europe |url=https://www.okapiconservation.org/zoo-network-europe-2/ |website=okapiconservation.org |access-date=2017-11-25}}</ref>
In Europe, zoos that exhibit and breed okapis include: [[Chester Zoo]], [[London Zoo]], [[Marwell Zoo]], [[Wild Place Project|The Wild Place]],<ref>{{cite web|url=https://bristolzoo.org.uk/latest-zoo-news/helping-to-protect-endangered-species-around-the-world |title=Helping to protect endangered species around the world |date=2019-05-17 |work=Bristol Zoo |access-date=2021-02-23}}</ref> and [[Yorkshire Wildlife Park]]<ref>{{cite web|url=https://www.yorkshirewildlifepark.com/okapi-arrival/ |title=Rare Okapi Arrive at Yorkshire Wildlife Park |date=2018-05-17 |work=Yorkshire Wildlife Park |access-date=2021-02-23}}</ref> (United Kingdom); [[Dublin Zoo]] (Ireland); [[Berlin Zoo]], [[Frankfurt Zoological Garden|Frankfurt Zoo]], [[Wilhelma|Wilhelma Zoo]], [[Wuppertal Zoo]], [[Cologne Zoological Garden|Cologne Zoo]], and [[Leipzig Zoological Garden|Leipzig Zoo]] (Germany); [[Basel Zoo|Zoo Basel]] (Switzerland); [[Copenhagen Zoo]] (Denmark); [[Diergaarde Blijdorp|Rotterdam Zoo]] and [[Safaripark Beekse Bergen]] (Netherlands); [[Antwerp Zoo]] (Belgium); [[Dvůr Králové Zoo]] (Czech Republic); [[Wrocław Zoo]] (Poland); [[Zoo de Doué|Bioparc Zoo de Doué]] and [[ZooParc de Beauval]] (France); and [[Lisbon Zoo]] (Portugal).<ref>{{cite web |title=Okapi Conservation Project {{!}} Europe |url=https://www.okapiconservation.org/zoo-network-europe-2/ |website=okapiconservation.org |access-date=2017-11-25 |archive-date=1 December 2017 |archive-url=https://web.archive.org/web/20171201042836/https://www.okapiconservation.org/zoo-network-europe-2/ |url-status=dead }}</ref>


In Asia, three Japanese zoos exhibit okapis: [[Ueno Zoo]] in Tokyo; [[Kanazawa Zoo]] and [[Zoorasia]] in Yokohama.<ref>{{cite web|title=Okapi Conservation Project {{!}} Asia |url=https://www.okapiconservation.org/zoo-network-asia/ |website=okapiconservation.org |access-date=2019-05-13}}</ref>
In Asia, three Japanese zoos exhibit okapis: [[Ueno Zoo]] in Tokyo; [[Kanazawa Zoo]] and [[Zoorasia]] in Yokohama.<ref>{{cite web |title=Okapi Conservation Project {{!}} Asia |url=https://www.okapiconservation.org/zoo-network-asia/ |website=okapiconservation.org |access-date=2019-05-13 |archive-date=5 February 2021 |archive-url=https://web.archive.org/web/20210205133110/https://www.okapiconservation.org/zoo-network-asia/ |url-status=dead }}</ref>


== See also ==
{{Portal|Africa}}
* {{Portal-inline|Africa}}
* {{Portal-inline|Mammals}}


==References==
==References==
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==Further reading==
==Further reading==
* Wolfram Bell (Nov. 2009): ''Okapis: geheimnisvolle Urwaldgiraffen; Entdeckungsgeschichte, Biologie, Haltung und Medizin einer seltenen Tierart''. Schüling Verlag Münster, Germany. {{ISBN|978-3-86523-144-4}}.
* Bell, Wolfram (Nov. 2009). ''Okapis: geheimnisvolle Urwaldgiraffen; Entdeckungsgeschichte, Biologie, Haltung und Medizin einer seltenen Tierart''. Schüling Verlag Münster, Germany. {{ISBN|978-3-86523-144-4}}.
* Zvi Sever, [https://onlinelibrary.wiley.com/doi/10.1111/aje.12796 Searching for the okapi (Okapia johnstoni) in Semuliki National Park], Uganda. Afr. J. Ecol. Vol. 00: 1–7. {{doi|10.1111/aje.12796}}
* Sever, Zvi (March 2021). "[https://onlinelibrary.wiley.com/doi/10.1111/aje.12796 Searching for the okapi (Okapia johnstoni) in Semuliki National Park, Uganda]". ''Afr. J. Ecol.'' Vol. 59, issue 1: 1–7. {{doi|10.1111/aje.12796}}.


==External links==
==External links==
{{Commons and category|Okapia johnstoni|Okapia johnstoni}}
{{Commons and category|Okapia johnstoni|Okapia johnstoni}}
{{Wiktionary}}
{{Wiktionary}}
* [http://www.theokapi.org The okapi management site]

* [http://catalog.hathitrust.org/Record/001502940 ''Monograph of the Okapi''] (1910) by [[E. Ray Lankester]] and William George Ridewood
*[http://www.theokapi.org The okapi management site]
* {{Cite EB1911|wstitle=Okapi|short=x}}
*[http://catalog.hathitrust.org/Record/001502940 ''Monograph of the Okapi''] (1910) by [[E. Ray Lankester]] and William George Ridewood
* {{cite web|title=Fun Facts for World Okapi Day|date=October 18, 2018|publisher=San Diego Zoo|website=YouTube|url=https://www.youtube.com/watch?v=1ryjzEWwZtA}}
*{{Cite EB1911|wstitle=Okapi|short=x}}
* {{cite web|title=5 Weird, Wild & Wonderful Facts About Okapi|date=October 20, 2019|publisher=Brookfield Zoo Chicago|website=YouTube|url=https://www.youtube.com/watch?v=2G8XsyNSIjo}}


{{Artiodactyla|R.}}
{{Artiodactyla|R.}}
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[[Category:Northeastern Congolian lowland forests]]
[[Category:Northeastern Congolian lowland forests]]
[[Category:Taxa named by Philip Sclater]]
[[Category:Taxa named by Philip Sclater]]
[[Category:Articles containing video clips]]

Latest revision as of 01:19, 25 November 2024

Okapi
Male okapi at Beauval Zoo
Female okapi at Zoo Miami
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Family: Giraffidae
Genus: Okapia
Lankester, 1901
Species:
O. johnstoni
Binomial name
Okapia johnstoni
(P.L. Sclater, 1901)
Range of the okapi

The okapi (/ˈkɑːp/; Okapia johnstoni), also known as the forest giraffe, Congolese giraffe and zebra giraffe, is an artiodactyl mammal that is endemic to the northeast Democratic Republic of the Congo in central Africa. However, non-invasive genetic identification has suggested that a population has occurred south-west of the Congo River as well.[2] It is the only species in the genus Okapia. Although the okapi has striped markings reminiscent of zebras, it is most closely related to the giraffe. The okapi and the giraffe are the only living members of the family Giraffidae.

The okapi stands about 1.5 m (4 ft 11 in) tall at the shoulder and has a typical body length around 2.5 m (8 ft 2 in). Its weight ranges from 200 to 350 kg (440 to 770 lb). It has a long neck, and large, flexible ears. Its coat is a chocolate to reddish brown, much in contrast with the white horizontal stripes and rings on the legs, and white ankles. Male okapis have short, distinct horn-like protuberances on their heads called ossicones, less than 15 cm (5.9 in) in length. Females possess hair whorls, and ossicones are absent.

Okapis are primarily diurnal, but may be active for a few hours in darkness. They are essentially solitary, coming together only to breed. Okapis are herbivores, feeding on tree leaves and buds, grasses, ferns, fruits, and fungi. Rut in males and estrus in females does not depend on the season. In captivity, estrus cycles recur every 15 days. The gestational period is around 440 to 450 days long, following which usually a single calf is born. The juveniles are kept in hiding, and nursing takes place infrequently. Juveniles start taking solid food from three months, and weaning takes place at six months.

Okapis inhabit canopy forests at altitudes of 500–1,500 m (1,600–4,900 ft). The International Union for the Conservation of Nature and Natural Resources classifies the okapi as endangered. Major threats include habitat loss due to logging and human settlement. Illegal mining and extensive hunting for bushmeat and skin have also led to a decline in populations. The Okapi Conservation Project was established in 1987 to protect okapi populations.

Etymology and taxonomy

[edit]
Strips cut from the striped part of the skin of an okapi, sent home by Sir Harry Johnston, were the first evidence of the okapi's existence to reach Europe.

Although the okapi was unknown to the Western world until the 20th century, it may have been depicted since the early fifth century BCE on the façade of the Apadana at Persepolis, a gift from the Ethiopian procession to the Achaemenid kingdom.[3][4]

For years, Europeans in Africa had heard of an animal that they came to call the African unicorn.[5][6] The animal was brought to prominent European attention by speculation on its existence found in press reports covering Henry Morton Stanley's journeys in 1887. In his travelogue of exploring the Congo, Stanley mentioned a kind of donkey that the natives called the atti, which scholars later identified as the okapi.[citation needed]

When the British special commissioner in Uganda, Sir Harry Johnston, discovered some Pygmy inhabitants of the Congo being abducted by a showman for exhibition, he rescued them and promised to return them to their homes. The Pygmies fed Johnston's curiosity about the animal mentioned in Stanley's book. Johnston was puzzled by the okapi tracks the natives showed him; while he had expected to be on the trail of some sort of forest-dwelling horse, the tracks were of a cloven-hoofed beast.[7]

Illustration from an original painting by Sir Harry Johnston, based on preserved skins (1901)

Though Johnston did not see an okapi himself, he did manage to obtain pieces of striped skin and eventually a skull. From this skull, the okapi was correctly classified as a relative of the giraffe; in 1901, the species was formally recognized as Okapia johnstoni.[8]

Okapia johnstoni was first described as Equus johnstoni by English zoologist Philip Lutley Sclater in 1901.[9] The generic name Okapia derives either from the Mbuba name okapi[10] or the related Lese Karo name o'api, while the specific name (johnstoni) is in recognition of Johnston, who first acquired an okapi specimen for science from the Ituri Forest.[8][11]

In 1901, Sclater presented a painting of the okapi before the Zoological Society of London that depicted its physical features with some clarity. Much confusion arose regarding the taxonomical status of this newly discovered animal. Sir Harry Johnston himself called it a Helladotherium, or a relative of other extinct giraffids.[12] Based on the description of the okapi by Pygmies, who referred to it as a "horse", Sclater named the species Equus johnstoni.[13] Subsequently, zoologist Ray Lankester declared that the okapi represented an unknown genus of the Giraffidae, which he placed in its own genus, Okapia, and assigned the name Okapia johnstoni to the species.[14]

In 1902, Swiss zoologist Charles Immanuel Forsyth Major suggested the inclusion of O. johnstoni in the extinct giraffid subfamily Palaeotraginae. However, the species was placed in its own subfamily Okapiinae, by Swedish palaeontologist Birger Bohlin in 1926,[15] mainly due to the lack of a cingulum, a major feature of the palaeotragids.[16] In 1986, Okapia was finally established as a sister genus of Giraffa on the basis of cladistic analysis. The two genera together with Palaeotragus constitute the tribe Giraffini.[17]

Evolution

[edit]
Despite the vast difference in neck length, the okapi (left) and the giraffe (right) both have seven cervical vertebrae (as do all mammals except for manatees and sloths).

The earliest members of the Giraffidae first appeared in the early Miocene in Africa, having diverged from the superficially deer-like climacoceratids. Giraffids spread into Europe and Asia by the middle Miocene in a first radiation. Another radiation began in the Pliocene, but was terminated by a decline in diversity in the Pleistocene.[18] Several important primitive giraffids existed more or less contemporaneously in the Miocene (23–10 million years ago), including Canthumeryx, Giraffokeryx, Palaeotragus, and Samotherium. According to palaeontologist and author Kathleen Hunt, Samotherium split into Okapia (18 million years ago) and Giraffa (12 million years ago).[19] However, J. D. Skinner argued that Canthumeryx gave rise to the okapi and giraffe through the latter three genera and that the okapi is the extant form of Palaeotragus.[20] The okapi is sometimes referred to as a living fossil, as it has existed as a species over a long geological time period, and morphologically resembles more primitive forms (e.g. Samotherium).[14][21]

In 2016, a genetic study found that the common ancestor of giraffe and okapi lived about 11.5 million years ago.[22]

Description

[edit]
Male okapi displaying his striking horizontal stripes

The okapi is a medium-sized giraffid, standing 1.5 m (4 ft 11 in) tall at the shoulder. Its average body length is about 2.5 m (8 ft 2 in) and its weight ranges from 200 to 350 kg (440 to 770 lb).[23] It has a long neck, and large and flexible ears. In sharp contrast to the white horizontal stripes on the legs and white ankles, the okapi's coat is a chocolate to reddish brown. The distinctive stripes resemble those of a zebra.[24] These features serve as an effective camouflage amidst dense vegetation. The face, throat, and chest are greyish white. Interdigital glands are present on all four feet, and are slightly larger on the front feet.[25] Male okapis have short, hair-covered horn-like structures called ossicones, less than 15 cm (5.9 in) in length, which are similar in form and function to the ossicones of a giraffe.[26] The okapi exhibits sexual dimorphism, with females 4.2 cm (1.7 in) taller on average, slightly redder, and lacking prominent ossicones, instead possessing hair whorls.[27][28]

The okapi shows several adaptations to its tropical habitat. The large number of rod cells in the retina facilitate night vision, and an efficient olfactory system is present. The large auditory bullae of the temporal bone allow a strong sense of hearing. The dental formula of the okapi is 0.0.3.33.1.3.3.[25] Teeth are low-crowned and finely cusped, and efficiently cut tender foliage. The large cecum and colon help in microbial digestion, and a quick rate of food passage allows for lower cell wall digestion than in other ruminants.[29]

Head of a male okapi with damaged ossicones

The okapi is easily distinguished from its nearest extant relative, the giraffe. It is much smaller than the giraffe and shares more external similarities with bovids and cervids. Ossicones are present only in the male okapi, while both sexes of giraffe possess this feature. The okapi has large palatine sinuses (hollow cavities in the palate), unique among the giraffids. Morphological features shared between the giraffe and the okapi include a similar gait – both use a pacing gait, stepping simultaneously with the front and the hind leg on the same side of the body, unlike other ungulates that walk by moving alternate legs on either side of the body[30] – and a long, black tongue (longer in the okapi) useful for plucking buds and leaves, as well as for grooming.[29]

Ecology and behaviour

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Okapis are primarily diurnal, but may be active for a few hours in darkness.[31] They are essentially solitary, coming together only to breed. They have overlapping home ranges and typically occur at densities around 0.6 animals per square kilometre.[24] Male home ranges average 13 km2 (5.0 sq mi), while female home ranges average 3–5 km2 (1.2–1.9 sq mi). Males migrate continuously, while females are sedentary.[32] Males often mark territories and bushes with their urine, while females use common defecation sites. Grooming is a common practice, focused at the earlobes and the neck. Okapis often rub their necks against trees, leaving a brown exudate.[25]

The male is protective of his territory, but allows females to pass through the domain to forage. Males visit female home ranges at breeding time.[29] Although generally tranquil, the okapi can kick and butt with its head to show aggression. As the vocal cords are poorly developed, vocal communication is mainly restricted to three sounds — "chuff" (contact calls used by both sexes), "moan" (by females during courtship) and "bleat" (by infants under stress). Individuals may engage in Flehmen response, a visual expression in which the animal curls back its upper lips, displays the teeth, and inhales through the mouth for a few seconds. The leopard is the main natural predator of the okapi.[25]

Diet

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The long tongue of the okapi

Okapis are herbivores, feeding on tree leaves and buds, branches, grasses, ferns, fruits, and fungi.[33] They are unique in the Ituri Forest as they are the only known mammal that feeds solely on understory vegetation, where they use their 18-inch-long (46 cm) tongues to selectively browse for suitable plants. The tongue is also used to groom their ears and eyes.[34] They prefer to feed in treefall gaps. The okapi has been known to feed on over 100 species of plants, some of which are known to be poisonous to humans and other animals. Fecal analysis shows that none of those 100 species dominates the diet of the okapi. Staple foods comprise shrubs and lianas. The main constituents of the diet are woody, dicotyledonous species; monocotyledonous plants are not eaten regularly. In the Ituri forest, the okapi feeds mainly upon the plant families Acanthaceae, Ebenaceae, Euphorbiaceae, Flacourtiaceae, Loganiaceae, Rubiaceae, and Violaceae.[25][32]

Reproduction

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A female okapi with her calf at White Oak Conservation

Female okapis become sexually mature at about one-and-a-half years old, while males reach maturity after two years. Rut in males and estrus in females does not depend on the season. In captivity, estrous cycles recur every 15 days.[29][35] The male and the female begin courtship by circling, smelling, and licking each other. The male shows his interest by extending his neck, tossing his head, and protruding one leg forward. This is followed by mounting and copulation.[27]

The gestational period is around 440 to 450 days long, following which usually a single calf is born, weighing 14–30 kg (31–66 lb). The udder of the pregnant female starts swelling 2 months before parturition, and vulval discharges may occur. Parturition takes 3–4 hours, and the female stands throughout this period, though she may rest during brief intervals. The mother consumes the afterbirth and extensively grooms the infant. Her milk is very rich in proteins and low in fat.[29]

As in other ruminants, the infant can stand within 30 minutes of birth. Although generally similar to adults, newborn calves have long hairs around the eye (resembling false eyelashes), a long dorsal mane, and long white hairs in the stripes.[36] These features gradually disappear and give way to the general appearance within a year. The juveniles are kept in hiding, and nursing takes place infrequently. Calves are known not to defecate for the first month or two of life, which is hypothesized to help avoid predator detection in their most vulnerable phase of life.[37] The growth rate of calves is appreciably high in the first few months of life, after which it gradually declines. Juveniles start taking solid food from 3 months, and weaning takes place at 6 months. Ossicone development in males takes 1 year after birth. The okapi's typical lifespan is 20–30 years.[25]

Distribution and habitat

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The okapi is endemic to the Democratic Republic of the Congo, where it occurs north and east of the Congo River. It ranges from the Maiko National Park northward to the Ituri rainforest, then through the river basins of the Rubi, Lake Tele, and Ebola to the west and the Ubangi River further north. Smaller populations exist west and south of the Congo River. It is also common in the Wamba and Epulu areas. It is extinct in Uganda.[1]

The okapi inhabits canopy forests at elevations of 500–1,500 m (1,600–4,900 ft). It occasionally uses seasonally inundated areas, but does not occur in gallery forests, swamp forests, and habitats disturbed by human settlements. In the wet season, it visits rocky inselbergs that offer forage uncommon elsewhere. Results of research conducted in the late 1980s in a mixed Cynometra forest indicated that the okapi population density averaged 0.53 animals per square kilometre.[32] In 2008, it was recorded in Virunga National Park.[38] There is also evidence that okapis were also observed in the Semuliki Valley in Uganda by Europeans, but later became extinct in the late 1970s.[39] The Semuliki Valley provides a similar habitat to the Congo Basin.

Status

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Threats and conservation

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Okapi at Disney's Animal Kingdom

The IUCN classifies the okapi as endangered.[40] It is fully protected under Congolese law. The Okapi Wildlife Reserve and Maiko National Park support significant populations of the okapi, though a steady decline in numbers has occurred due to several threats. Other areas of occurrence are the Rubi Tele Hunting Reserve ,the Abumombanzi Reserve,the Sankuru Nature Reserve, the Lomami National Park. Major threats include habitat loss due to logging and human settlement. Extensive hunting for bushmeat and skin and illegal mining have also led to population declines. A threat that has emerged quite recently is the presence of illegal armed groups around protected areas, inhibiting conservation and monitoring actions. A small population occurs north of the Virunga National Park, but lacks protection due to the presence of armed groups in the vicinity.[1] In June 2012, a gang of poachers attacked the headquarters of the Okapi Wildlife Reserve, killing six guards and other staff[41] as well as all 14 okapis at their breeding center.[42]

The Okapi Conservation Project, established in 1987, works towards the conservation of the okapi, as well as the growth of the indigenous Mbuti people.[1] In November 2011, the White Oak Conservation center and Jacksonville Zoo and Gardens hosted an international meeting of the Okapi Species Survival Plan and the Okapi European Endangered Species Programme at Jacksonville, which was attended by representatives from zoos from the US, Europe, and Japan. The aim was to discuss the management of captive okapis and arrange support for okapi conservation. Many zoos in North America and Europe currently have okapis in captivity.[43]

Okapis in zoos

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1960 Dutch newsreel about okapis in Diergaarde Blijdorp

Around 100 okapis are in accredited Association of Zoos and Aquariums (AZA) zoos. The okapi population is managed in America by the AZA's Species Survival Plan, a breeding program that works to ensure genetic diversity in the captive population of endangered animals, while the EEP (European studbook) and ISB (Global studbook) are managed by Antwerp Zoo in Belgium, which was the first zoo to have an Okapi on display (in 1919), as well as one of the most successful in breeding them.[44][45]

In 1937, the Bronx Zoo became the first in North America to acquire an okapi.[46] With one of the most successful breeding programs, 13 calves have been born there between 1991 and 2011.[47] The San Diego Zoo has exhibited okapis since 1956, and their first okapi calf was born in 1962.[48] Since then, there have been more than 60 okapis born at the zoo and the nearby San Diego Zoo Safari Park, the most recent being Mosi, a male calf born on 21 July 2017 at the zoo.[49] The Brookfield Zoo in Chicago has also greatly contributed to the captive population of okapis in accredited zoos. The zoo has had 28 okapi births since 1959.[50]

Other North American zoos that exhibit and breed okapis include: Denver Zoo and Cheyenne Mountain Zoo (Colorado); Houston Zoo, Dallas Zoo, and San Antonio Zoo (Texas); Disney's Animal Kingdom, White Oak Conservation, Zoo Miami, and ZooTampa at Lowry Park (Florida); Los Angeles Zoo, Sacramento Zoo, and San Diego Zoo (California); Saint Louis Zoo (Missouri); Cincinnati Zoo and Botanical Garden and Columbus Zoo and Aquarium (Ohio); Memphis Zoo and Nashville Zoo (Tennessee); The Maryland Zoo in Baltimore (Maryland); Sedgwick County Zoo and Tanganyika Wildlife Park (Kansas); Roosevelt Park Zoo[51] (North Dakota); Henry Doorly Zoo and Aquarium (Nebraska); Philadelphia Zoo (Pennsylvania); Potawatomi Zoo[52] (Indiana); Oklahoma City Zoo and Botanical Garden (Oklahoma); Blank Park Zoo (Iowa);[53] and Potter Park Zoo (Michigan).[54]

In Europe, zoos that exhibit and breed okapis include: Chester Zoo, London Zoo, Marwell Zoo, The Wild Place,[55] and Yorkshire Wildlife Park[56] (United Kingdom); Dublin Zoo (Ireland); Berlin Zoo, Frankfurt Zoo, Wilhelma Zoo, Wuppertal Zoo, Cologne Zoo, and Leipzig Zoo (Germany); Zoo Basel (Switzerland); Copenhagen Zoo (Denmark); Rotterdam Zoo and Safaripark Beekse Bergen (Netherlands); Antwerp Zoo (Belgium); Dvůr Králové Zoo (Czech Republic); Wrocław Zoo (Poland); Bioparc Zoo de Doué and ZooParc de Beauval (France); and Lisbon Zoo (Portugal).[57]

In Asia, three Japanese zoos exhibit okapis: Ueno Zoo in Tokyo; Kanazawa Zoo and Zoorasia in Yokohama.[58]

See also

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References

[edit]
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  2. ^ Stanton, D.; Hart, J.; Vosper, A.; Kümpel, N.; Wang, J.; Ewen, J.; Bruford, M. (2016). "Non-invasive genetic identification confirms the presence of the Endangered okapi Okapia johnstoni south-west of the Congo River". Oryx. 50 (1): 134–137. doi:10.1017/S0030605314000593.
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Further reading

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