Editing Plains zebra (section)

==Taxonomy==
The plains zebra was formally classified by British zoologist [[John Edward Gray]] in 1824 as ''Equus burchellii''. After the quagga, described by [[Pieter Boddaert]] in 1785, was found to be the same species in the 21st century, the plains zebra was reclassified as ''Equus quagga'' due to the [[principle of priority]].<ref>{{cite journal|author=Heywood, P.|year=2015|title=The Micro-politics of Macromolecules in the Taxonomy and Restoration of Quaggas|journal=Kronos|volume=41|issue=1|pages=314–337|url=http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0259-01902015000100013}}</ref> The plains zebra and [[mountain zebra]] were traditionally placed in the [[subgenus]] ''Hippotigris'', in contrast to [[Grévy's zebra]], which was considered the sole species of the subgenus ''Dolichohippus'';<ref name="Prothero 2003">{{Cite book|title=Horns, Tusks, and Flippers: The Evolution of Hoofed Mammals'|author1=Prothero D.R |author2=Schoch R. M |url=https://books.google.com/books?id=kWpQX-sfsLgC&q=Horns,+Tusks,+and+Flippers:+The+Evolution+of+Hoofed+Mammals|publisher=Johns Hopkins University Press|pages=216–18|year=2003|isbn=978-0-801-87135-1}}</ref> however, recent (2013) [[phylogenetic]] evidence finds that plains zebras are more closely related to Grévy's zebras than mountain zebras.<ref name=Vilstrup>{{cite journal|author=Vilstrup, Julia T.|year=2013|title=Mitochondrial Phylogenomics of Modern and Ancient Equids|journal=PLOS ONE|volume=8|issue=2|page=e55950|doi=10.1371/journal.pone.0055950|display-authors=etal|pmid=23437078|pmc=3577844|bibcode=2013PLoSO...855950V|doi-access=free}}</ref> Groves and Bell (2004) place all three species in the subgenus ''Hippotigris'',<ref name="GrovesBell2004">{{cite journal|author=Groves, C. P.; Bell, C. H.|year=2004|title=New investigations on the taxonomy of the zebras genus ''Equus'', subgenus ''Hippotigris''|journal=Mammalian Biology|volume=69|issue=3|pages=182–196|doi=10.1078/1616-5047-00133|bibcode=2004MamBi..69..182G }}</ref> and zebras appear to be a [[monophyletic]] lineage.<ref name=Vilstrup/> In areas where plains zebras are [[sympatric]] with Grévy's zebras, finding them in the same herds is not unusual,<ref name="Estes 1991">{{cite book|author=Estes, R.|year=1991|title=The Behavior Guide to African Mammals, Including Hoofed Mammals, Carnivores, Primates|url=https://archive.org/details/isbn_0520080858|url-access=registration|publisher=University of California Press|pages=[https://archive.org/details/isbn_0520080858/page/242 242–246]|isbn=978-0-520-08085-0}}</ref> and [[Zebroid|fertile hybrids]] occur.<ref>{{cite journal|author=J. E. Cordingley, S. R. Sundaresan, I. R. Fischhoff, B. Shapiro, J. Ruskey, D. I. Rubenstein|year=2009|title=Is the endangered Grevy's zebra threatened by hybridization?|journal=Animal Conservation|volume=12|issue=6|pages=505–513|doi=10.1111/j.1469-1795.2009.00294.x|bibcode=2009AnCon..12..505C |s2cid=18388598}}</ref>

===Subspecies===
In their 2004 study of cranial and pelage differences between specimens, Groves and Bell found support for the division of the plains zebra into six subspecies:<ref name="GrovesBell2004"/>
{| class="wikitable "
|-
! Image !! Subspecies !!  Distribution
|-
|[[File:Maneless zebras at Kidepo Valley NP - Uganda.jpg|150px]]||[[Maneless zebra]], ''Equus quagga borensis'' – Lönnberg, 1921 ||  Northwestern [[Kenya]] (from [[Uasin Gishu County|Uasin Gishu]] and [[Lake Baringo]]) to the [[Karamoja]] district of [[Uganda]].
|-
|[[File:Equus quagga.jpg|150px]]||[[Grant's zebra]], ''Equus quagga boehmi'' – Matschie, 1892 ||  [[Zambia]] west of the [[Luangwa River]] and west to Kariba, [[Katanga Province]] of the [[Democratic Republic of the Congo]], north to the Kibanzao Plateau, and in [[Tanzania]] north from Nyangaui and [[Kibwezi]] into southwestern Kenya as far as [[Sotik Constituency|Sotik]] and southwestern [[Ethiopia]] from [[Omo National Park|Omo Valley]] to [[Nechisar National Park|Nechisar plains]] in the north and [[Yabelo Wildlife Sanctuary|Yabello]] and [[Borena National Park|Borena Zone]] to the east. 
|-
|[[File:Zebra Side.JPG|150px]]||[[Crawshay's zebra]], ''Equus quagga crawshayi'' – De Winton, 1896 || Eastern Zambia, east of the Luangwa River, [[Malawi]], southeastern Tanzania, and northern [[Mozambique]] south to the Gorongoza District
|-
|[[File:Burchell's Zebra (Equus quagga burchellii) (15844593253).jpg|150px]]|| [[Chapman's zebra]], ''Equus quagga chapmani'' – Layard, 1865 ||  North-east [[South Africa]], north to Zimbabwe, west into [[Botswana]], the [[Caprivi Strip]] in [[Namibia]], and southern [[Angola]].
|-
|[[File:Equus quagga burchellii - Etosha, 2014.jpg|150px]]<!--Common zebra 1.jpg-->|| [[Burchell's zebra]], ''Equus quagga burchellii'' – Gray, 1824 || Southern Botswana to Etosha and the [[Kaokoveld]], and southeast to [[Eswatini]] and [[KwaZulu-Natal]]. 
|-
|[[File:Quagga Naturhistorisches Museum Basel 27102013 3.jpg|150px]]|| [[Quagga]], [[Extinction|†]]''Equus quagga quagga'' – Boddaert, 1785||  South Africa 
|-
|[[File:Zeitschrift für wissenschaftliche Zoologie (1906) (14762972812).jpg|150px]]|| [[Selous' zebra]], ''Equus quagga selousi'' – Pocock, 1897*|| Mozambique
|-
|}
<nowiki>*</nowiki>Sometimes a seventh subspecies is recognised.<ref>{{cite book|author=Beolens, B.; Watkins, M.; Grayson, M.|year=2009|title=The Eponym Dictionary of Mammals|publisher=Johns Hopkins University Press|pages=167|isbn=978-0801893049}}</ref>

Burchell's zebra was thought to have been hunted to extinction. However, Groves and Bell concluded that "the extinct true Burchell's zebra is a phantom". Careful study of the original zebra populations in Zululand and Eswatini and of skins harvested on game farms in Zululand and Natal has revealed that a certain small proportion shows similarity to what now is regarded as typical ''burchellii''. The type localities of the subspecies ''Equus quagga burchellii'' and ''Equus quagga antiquorum'' are so close to each other that the two are in fact one and that, therefore, the older of the two names should take precedence over the younger. They suggested that the correct name for the subspecies must be ''burchellii'', not ''antiquorum''.<ref name="GrovesBell2004"/>

A 2005 genetic study confirmed the quagga being the same species as the plains zebra. It showed that the quagga had little genetic diversity and that it diverged from the other plains zebra subspecies only 120,000–290,000 years ago, during the [[Pleistocene]] and, possibly, the penultimate glacial maximum. Its distinct coat pattern may have evolved rapidly because of geographical isolation and/or adaptation to a drier environment. In addition, plains zebra subspecies tend to have less striping the further south they live, and the quagga was the most southern-living of them all.<ref name="smithsonian">{{Cite journal |last1=Hofreiter |first1=M. |last2=Caccone |first2=A. |last3=Fleischer |first3=R. C. |last4=Glaberman |first4=S. |last5=Rohland |first5=N. |last6=Leonard |first6=J. A. |doi=10.1098/rsbl.2005.0323 |title=A rapid loss of stripes: The evolutionary history of the extinct quagga |journal=Biology Letters |volume=1 |issue=3 |pages=291–295 |year=2005 |pmid=17148190 |pmc=1617154}}</ref>

The simplified [[cladogram]] below is based on the 2005 analysis (some taxa shared [[haplotype]]s and could therefore not be differentiated):<ref name="smithsonian"/>
{{clade| style=font-size:100%; line-height:100%
|1={{clade
 |1=[[Mountain zebra]] (''E. zebra'')
 |2={{clade
  |1=[[Grévy's zebra]] (''E. grevyi'')
  |2={{clade
    |1={{clade
     |1='''Quagga''' ('''''E. q. quagga''''')
     |2=[[Damara zebra]] (''E. q. antiquorum'')-[[Chapman's zebra]] (''E. q. chapmani'')}}
    |2=[[Grant's zebra]] (''E. q. boehmi'') }}
  }}
 }}
}}

A 2018 DNA study found no evidence for a subspecies structure in plains zebras but, instead, observed a north–south genetic continuum. Modern plains zebra populations appear to have originated from Southern Africa around 370,000 years ago with plains zebras in Uganda, the most northern population, being the most distinct.<ref name="PedersenAlbrechtsen2018">{{cite journal |last1=Pedersen |first1=Casper-Emil T. |last2=Albrechtsen |first2=Anders |last3=Etter |first3=Paul D. |last4=Johnson |first4=Eric A. |last5=Orlando |first5=Ludovic |last6=Chikhi |first6=Lounes |last7=Siegismund |first7=Hans R. |last8=Heller |first8=Rasmus |year=2018|title=A southern African origin and cryptic structure in the highly mobile plains zebra |journal=Nature Ecology & Evolution |volume=2 |issue=3 |pages=491–498 |issn=2397-334X |doi=10.1038/s41559-017-0453-7 |pmid=29358610 |bibcode=2018NatEE...2..491P |s2cid=3333849 }}</ref>