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Quagga
Live female quagga in London Zoo, 1870
Conservation status
Extinct (1883)  (IUCN 3.1)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Perissodactyla
Family:	Equidae
Genus:	Equus
Subgenus:	Hippotigris
Species:	E. quagga
Subspecies:	†E. q. quagga
Trinomial name
†Equus quagga quagga Boddaert, 1785

The quagga (Equus quagga quagga) is an extinct subspecies of the plains zebra that lived in South Africa. It was long thought to be a distinct species, but recent genetic studies have shown it to be the southernmost subspecies of the plains zebra. Its name is derived from its call, which is reported to have sounded like "kwa-ha-ha".

The quagga was distinguished from other zebras by its limited pattern of primarily brown and white stripes, mainly on the front part of the body. The rear was brown and without stripes, and therefore more horse-like. The distribution of stripes varied considerably between individuals. Little is known about its behaviour. It gathered into herds of 30–50 individuals, and was sympatric with Burchell's zebra in some of its range. The quagga was once found in great numbers in the Karoo of the former Cape Province and the southern part of the former Orange Free State in South Africa.

Since Dutch settlement of South Africa began, the quagga was heavily hunted, and it competed with domesticated animals for forage. While some individuals were taken to zoos in Europe, breeding programs were not successful and the quagga was extinct in the wild by 1878. The last captive specimen died in Amsterdam on August 12, 1883. In 1984, the quagga was the first extinct animal to have its DNA analysed, and the Quagga Project has tried to recreate it by selectively breeding plains zebras to resemble it.

Taxonomy

The name "quagga" is derived from the Khoikhoi word for zebra and is onomatopoeic, being said to resemble the quagga's call. The name is still used colloquially for the plains zebra, which also has a call resembling "kwa-ha-ha". This sound has also been transliterated as "oug-ga, oug-ga". The quagga was originally classified as a distinct species, Equus quagga, in 1778 by Dutch naturalist Pieter Boddaert. The name has also been used for a subgenus, Quagga, by Shortridge in in 1934, which included the quagga and Burchell's zebra (Equus quagga burchellii). Today, the quagga and the other plains and mountain zebras are placed in the subgenus Hippotigris.

Some authors have found the quagga to be a kind of wild horse rather than a zebra, and one craniometric study from 1980 seemed to confirm its affiliation with the horse (Equus caballus). There has been much debate over the status of the quagga in relation to the plains zebra (Equus burchelli). It is poorly represented in the fossil record, and the identification of these fossils is unsure, as they were collected at a time when the name quagga referred to all zebras. Fossil skulls from Algeria refereed to an Equus mauritanicus have been claimed to show affinities with the quagga and the plains zebra, but these may be too damaged to definitely conclude anything. The quagga has also been identified in cave art attributed to Bushmen.

Different subspecies of plains zebra were recognised as members of Equus quagga by early researchers, though there was much confusion over which species were valid. It has also been pointed out that early morphological studies were erroneous, since using skeletons from stuffed specimens might be problematical, as early taxidermists sometimes used donkey and horse skulls inside their mounts, when the originals were unavailable. Quagga subspecies were described based on differences in striping patterns, but these differences were since attributed to individual variation within the same populations. Reginald Innes Pocock was perhaps the first to suggest that the quagga was a subspecies of plains zebra in 1902. As the quagga was scientifically described and named before the plains zebra, the trinomial name for the quagga becomes E. quagga quagga under this scheme, and the other subspecies of plains zebra are placed under E. quagga as well.

Evolution

In 1984, the quagga was the first extinct animal to have its DNA studied. This article also launched the field of ancient DNA study. The study confirmed that the quagga was more closely related to zebras than to horses. It found that the quagga and mountain zebra (Equus zebra) shared an ancestor 3–4 million years ago. An immunological study published the following year found the quagga to be closest to the plains zebra. A 1987 study suggested that the mtDNA of the quagga diverged at a range of roughly 2% per every one million years, similar to other mammal species, and again confirmed the close relation to the plains zebra.

Later morphological studies came to conflicting conclusions. A 1999 analysis of cranial measurements found that the quagga was as different from the plains zebra as the latter is from the mountain zebra. A 2004 study of skins and skulls instead suggested that the quagga was not a distinct species, but a subspecies of the plains zebra. In spite of these findings, many authors subsequently kept the plains zebra and the quagga as separate species.

A genetic study published in 2005 confirmed the sub-specific status of the quagga. It showed that the quagga had little genetic diversity, and that it diverged from the other plains zebra subspecies only between 120,000 and 290,000 years ago, during the Pleistocene, and possibly the penultimate glacial maximum. Its distinct coat pattern likely evolved rapidly due to 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. Other large African ungulates diverged into separate species and subspecies during this period as well, probably due to the same climate shift.

Description

The quagga is believed to have been 257 cm (8.43 ft) long and stood 125–135 cm (4.10–4.43 ft) tall. The coat pattern of the quagga was unique among equids. It was zebra-like in the front part, but its rear part looked more like a horse. It had brown stripes on the head and neck, brown upper parts and a white belly, tail and legs. The stripes were darkest on the head and neck, and became gradually lighter further down the body, blending with the reddish brown of the back and flanks, until disappearing along the back. However it appears to have had a high degree of polymorphism, with some individuals having almost no stripes and others having striping patterns similar to Burchell's zebra , where the stripes covers most of the body except for the hindparts, legs and belly. It also had a broad dark dorsal stripe on its back. It had a standing mane, with brown and white stripes.

The only quagga to have been photographed alive was a mare at the Zoological Society of London's Zoo; it died in 1872. On the basis of some accounts and photographs, it has been suggested that the stripes were light, contrary to the configuration in other zebras. But it has been pointed out that this is an optical illusion, and that the base colour of the head, shoulders, and other parts was a creamy white, which is what gives this impression when seen between the actual dark stripes, typical of zebras. However, embryological evidence supports zebra being dark coloured with white as an addition.

Living in the very southern end of the plains zebra's range, the quagga possibly had a thick winter coat that moulted each year. Its skull was described as having a straight profile and a concave distema, and as being relatively broad, with a narrow occiput. The 2004 morphological study found that the skeletal features of Burchell's zebra and the quagga overlapped, and that they were impossible to distinguish. Some specimens also appeared to be intermediate between the two in striping. The female specimens used in the study were larger than the males on average. Like other plains zebras, the quagga did not have a dewlap on its neck, as is present on the mountain zebra.

Distribution

The quagga was the southernmost disturbed plains zebra, mainly living south of the Orange River. It was probably a grazer, and its habitat range was restricted to the grasslands and arid interior scrubland of the Karoo region of South Africa, today forming parts of the contemporary provinces of Northern Cape, Eastern Cape, Western Cape and the Free State. These areas were known for distinctive flora and fauna and high amounts of endemism.

Behaviour and ecology

Little is known about the quagga in life, and it is sometimes unclear what exact species of zebra is referred to in old reports. Quagga have been reported gathering into herds of 30–50 individuals and sometimes traveled in a linear fashion.

" The geographical range of the quagga does not appear to extend to the northward of the river Vaal. The animal was formerly extremely common within the colony ; but, vanishing before the strides of civilisation, is now to be found in very limited numbers and on the borders only. Beyond, on those sultry plains which are completely taken possession of by wild beasts, and may with strict propriety be termed the domains of savage nature, it occurs in interminable herds ; and, although never intermixing with its more elegant congeners, it is almost invariably to be found ranging with the white-tailed gnu and with the ostrich, for the society of which bird especially it evinces the most singular predilection. Moving slowly across the profile of the ocean-like horizon, uttering a shrill, barking neigh, of which its name forms a correct imitation, long files of quaggas continually remind the early traveller of a rival caravan on its march. Bands of many hundreds are thus frequently seen doing their migration from the dreary and desolate plains of some portion of the interior, which has formed their secluded abode, seeking for those more luxuriant pastures where, during the summer months, various herbs thrust forth their leaves and flowers to form a green carpet, spangled with hues the most brilliant and diversified."

— Major Sir William Cornwallis Harris, English military engineer, artist and hunter.

Captive individuals in European zoos were said to be tamer and more docile than Burchell's zebra. Local farmers even used them as guards for their livestock. One specimen was reported to have lived in captivity for 21 years and 4 months, until dying in 1872.

The quaggas may have been sympatic with Burchell's zebra between the Vaal and Orange rivers. However, this is disputed, and there is no evidence that they interbred. It could also have shared a small portion of its range with Hartmann's mountain zebra (Equus zebra hartmannae). The practical function of zebra striping has not been determined, and it is unclear why the quagga lost the stripes on its hind parts. A cryptic function for protection from predators and tsetse flies, as well as various social functions, have been proposed for zebras in general. Differences in hind quarter stripes may have aided species recognition during stampedes of mixed herds, so that members of one subspecies or species would follow its own kind. It has also been hypothesised that the zebras developed striping patterns as thermoregulation to cool themselves down, and that the quagga lost them due to living in a cooler climate, although one problem with this is that the mountain zebra lives in similar environments and has a bold striping pattern.

Decline and extinction

The quagga was hunted by early Dutch settlers from the 1600s, and later by their descendants the Afrikaners, as they were easy to find and kill. Their meat was eaten and their skins were traded or used locally. It is probable that the quagga was vulnerable to extinction due to its limited distribution and may have competed with domestic livestock for forage. The quagga had disappeared from much of its range by the 1850s, and the last wild population, living in the Orange Free State, was extirpated in the late 1870s. The last wild individual died in 1878.

Individual quaggas were also captured and shipped to Europe where they were displayed in zoos. Lord Morton tried to save the animal from extinction by starting a captive breeding program. However, he was only able to obtain a single male which, in desperation, he bred with a female horse. This produced a female hybrid which bore the zebra stripes on its back and legs. Lord Morton's mare was sold and was subsequently bred with a black stallion, resulting in offspring that again had zebra stripes. An account of this was published in 1820 by the Royal Society. This lead to new ideas on telegony, referred to as pan-genesis by Charles Darwin.

The last captive specimen, a female in Amsterdam's Natura Artis Magistra zoo, had lived there from May 9 1867 until it died on August 12 1883, and its origin and cause of death were not recorded. The specimen in London died in 1872 and the one in Berlin in 1875. There are 23 known stuffed and mounted quagga specimens throughout the world. A twenty-fourth specimen was destroyed in Königsberg, Germany, during World War II.

"Breeding back" project

After the very close relationship between the quagga and surviving zebras was discovered, the Quagga Project was started in 1986 by Reinhold Rau in South Africa to recreate the quagga by selective breeding from plains zebra stock, with the eventual aim of reintroducing them to the wild. The founding population consisted of 19 individuals from Namibia and South Africa, chosen because they had reduced striping on the rear body and legs. The first foal of the project was born in 1988. Once a sufficiently quagga-like population has been created, it will be released in the Western Cape. This type of selective breeding is also called breeding back. In early 2006, the third and fourth generation animals produced by the project were reported to look very much like the depictions and preserved specimens of the quagga. The practice of breeding back generally, and specifically whether optic similarity alone are enough to declare that this project has truly recreated the original quagga, are both controversial. The technology to use recovered DNA for breeding does not exist.

See also

• List of extinct animals

References

1. Template:IUCN2008
2. ^ Skinner, JD (2005). "Equidae". The Mammals of the Southern African Subregion (3rd ed.). Cambridge: Cambridge University Press. pp. 537–546. ISBN 0-521-84418-5. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
3. ^  This article incorporates text from a publication now in the public domain: Chisholm, Hugh, ed. (1911). "Quagga". Encyclopædia Britannica (11th ed.). Cambridge University Press.
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External links

• The Quagga Project
• PBS Nature: Restoring the Quagga
• Quagga Quest. Can we bring back a long-extinct animal? (Slate)
• Real Life Jurassic Park? Scientists claim to 'restore' extinct zebra (ABC News)

• IUCN Red List extinct species
• Extinct mammals
• Extinct mammals of Africa
• Mammals of South Africa
• Megafauna of Africa
• Zebras
• Mammal extinctions since 1500
• Species made extinct by human activities