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Zebra

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From Wikipedia, the free encyclopedia
Black-and-white striped animals in the equid family
Not to be confused withzebro.
For other uses, seeZebra (disambiguation).

Zebra
A herd of plains zebra ("Equus quagga")
Aplains zebra (Equus quagga) among a herd in theNgorongoro Crater inTanzania
Scientific classificationEdit this classification
Kingdom:Animalia
Phylum:Chordata
Class:Mammalia
Order:Perissodactyla
Family:Equidae
Genus:Equus
Subgenus:Hippotigris
C. H. Smith, 1841
Species

E. capensis
E. grevyi
E. mauritanicus
E. oldowayensis
E. quagga
E. zebra

Modern range of the three living zebra species

Zebras (US:/ˈzbrəz/,UK:/ˈzɛbrəz,ˈz-/)[2] (subgenusHippotigris) are Africanequines with distinctive black-and-white stripedcoats. There are threeliving species:Grévy's zebra (Equus grevyi), theplains zebra (E. quagga), and themountain zebra (E. zebra). Zebras share the genusEquus withhorses andasses, the three groups being the only living members of the familyEquidae. Zebra stripes come in different patterns, unique to each individual. Several theories have been proposed for the function of these patterns, with most evidence supporting them as a deterrent for biting flies. Zebras inhabiteastern andsouthern Africa and can be found in a variety of habitats such assavannahs,grasslands, woodlands,shrublands, and mountainous areas.

Zebras are primarilygrazers and can subsist on lower-quality vegetation. They are preyed on mainly bylions, and typically flee when threatened but also bite and kick. Zebra species differ insocial behaviour, with plains and mountain zebra living in stableharems consisting of an adult male orstallion, several adult females ormares, and their young orfoals; while Grévy's zebra live alone or in loosely associated herds. In harem-holding species, adult females mate only with their harem stallion, while male Grévy's zebras establishterritories which attract females and the species ispolygynandrous. Zebras communicate with various vocalisations, body postures and facial expressions.Social grooming strengthens social bonds in plains and mountain zebras.

Zebras' dazzling stripes make them among the most recognisable mammals. They have been featured in art and stories in Africa and beyond. Historically, they have been highly sought by exotic animal collectors, but unlikehorses anddonkeys, zebras have never been completelydomesticated. TheInternational Union for Conservation of Nature (IUCN) lists Grévy's zebra asendangered, the mountain zebra asvulnerable and the plains zebra asnear-threatened. Thequagga (E. quagga quagga), a type of plains zebra, was driven to extinction in the 19th century. Nevertheless, zebras can be found in numerous protected areas.

Etymology

The English name "zebra" derives fromItalian,Spanish orPortuguese.[3][4] Its origins may lie in theLatinequiferus, meaning "wild horse".Equiferus appears to have entered into Portuguese asezebro orzebro, which was originally used for amysterious equine reported in the wilds of theIberian Peninsula during the Middle Ages. In 1591, Italian explorerFilippo Pigafetta recorded "zebra" being used to refer to the African animals by Portuguese visitors to the continent.[5] In ancient times, the zebra was calledhippotigris ("horse tiger") by theGreeks andRomans.[5][6]

The wordzebra was traditionally pronounced with a long initial vowel, but over the course of the 20th century the pronunciation with the short initial vowel became the norm inBritish English.[7] The pronunciation with a long initial vowel remains standard inAmerican English.[8]

Taxonomy

Further information:Evolution of the horse

Zebras are classified in the genusEquus (known as equines) along withhorses andasses. These three groups are the only living members of the familyEquidae.[9] Theplains zebra andmountain zebra were traditionally placed in thesubgenusHippotigris (C. H. Smith, 1841) in contrast to theGrévy's zebra which was considered the sole species of subgenusDolichohippus (Heller, 1912).[10][11][12] Groves and Bell (2004) placed all three species in the subgenusHippotigris.[13] A 2013phylogenetic study found that the plains zebra is more closely related to Grévy's zebras than mountain zebras.[14] The extinctquagga was originally classified as a distinct species.[15] Later genetic studies have placed it as the same species as the plains zebra, either a subspecies or just the southernmost population.[16][17] Molecular evidence supports zebras as amonophyleticlineage.[14][18][19]

Equus originated in North America and directpaleogenomic sequencing of a 700,000-year-old middle Pleistocene horsemetapodial bone from Canada implies a date of 4.07 million years ago (mya) for the mostrecent common ancestor of the equines within a range of 4.0 to 4.5 mya.[20] Horsessplit from asses and zebras around this time and equines colonised Eurasia and Africa around 2.1–3.4 mya. Zebras and asses diverged from each other close to 2 mya. The mountain zebra diverged from the other species around 1.6 mya and the plains and Grévy's zebra split 1.4 mya.[21]

A 2017 mitochondrial DNA study placed the EurasianEquus ovodovi and the subgenusSussemionus lineage as closer to zebras than to asses.[22] However, other studies disputed this placement, finding theSussemionus lineage basal to the zebra+asses group, but suggested that theSussemionus lineage may have received gene flow from zebras.[23]

The cladogram ofEquus below is based on Vilstrup and colleagues (2013) and Jónsson and colleagues (2014):[14][21]

Equus
Zebras

Mountain zebra (E. zebra)

Plains zebra (E. quagga)

Grévy's zebra (E. grevyi)

Wild asses

Kiang (E. kiang)

Onager (E. hemionus)

African wild ass (E. africanus)

Horses

Horse (E. ferus caballus)

Przewalski's horse (E. ferus przewalski)

Extant species

NameDimensionsDescriptionDistributionSubspeciesChromosomesImage
Grévy's zebra (Equus grevyi)Body length: 250–300 cm (98–118 in)
Tail length: 38–75 cm (15–30 in)
Shoulder height: 125–160 cm (49–63 in)
Weight: 352–450 kg (776–992 lb).[24]
Thin, elongated skull, robust neck and conical ears; narrow striping pattern withconcentric rump stripes, white belly and tail base and white line around the ashy muzzle.[9][25][26]Eastern Africa includingthe Horn;[25] arid and semiaridgrasslands andshrublands.[27]Monotypic[25]46[27]
Plains zebra (Equus quagga)Body length: 217–246 cm (85–97 in)
Tail length: 47–56 cm (19–22 in)
Shoulder height: 110–145 cm (43–57 in)
Weight: 175–385 kg (386–849 lb).[24]
Thick bodied with relatively short legs and an obtusely shaped skull profile with a protruding forehead and a more recessed nose area;[9][28] broad stripes, horizontal on the rump, with northern populations having more extensive striping while populations further south have whiter legs and bellies and more brown "shadow" stripes while the snout is black.[9][29][30][31]Eastern andsouthern Africa;savannahs, grasslands and open woodlands.[32]6[13] or monotypic[17]44[33]
Mountain zebra (Equus zebra)Body length: 210–260 cm (83–102 in)
Tail length: 40–55 cm (16–22 in)
Shoulder height: 116–146 cm (46–57 in)
Weight: 204–430 kg (450–948 lb).[24]
Eye sockets more circular and positioned farther back, a squarernuchal crest,dewlap present under neck and compact hooves; stripes intermediate in width between the other species, with gridiron and horizontal stripes on the rump, while the belly is white and the black muzzle is lined withchestnut or orange.[34][9][35][27]Southwestern Africa; mountains, rocky uplands andKaroo shrubland.[32][34][31]2[34]32[27]

Fossil record

A fossil skull of Equus mauritanicu
Fossil skull ofEquus mauritanicus

In addition to the three living species, some fossil zebras and relatives have also been identified.E. oldowayensis is identified from remains in Olduvai Gorge dating to 1.8 mya.[36] Fossil skulls ofE. mauritanicus from Algeria which date to around 1 mya appears to show affinities with the plains zebra.[37][38]E. capensis, known as the Cape zebra, appeared around 2 mya and lived throughout southern and eastern Africa.[1][36]

Hybridisation

Main article:Zebroid

Fertile hybrids have been reported in the wild between plains and Grévy's zebra.[39] Hybridisation has also been recorded between the plains and mountain zebra, though it is possible that these are infertile due to the difference in chromosome numbers between the two species.[40] Captive zebras have been bred with horses anddonkeys; these are known aszebroids. A zorse is a cross between a zebra and a horse; a zonkey, between a zebra and a donkey; and a zoni, between a zebra and apony. Zebroids are often born sterile withdwarfism.[41]

  • Grévy's × plains zebra hybrid, alongside plains zebras
    Grévy's × plains zebra hybrid, alongside plains zebras
  • Donkey × plains zebra hybrid, in South Africa
    Donkey × plains zebra hybrid, in South Africa

Characteristics

Further information:Equine anatomy
Mounted skeleton of a Grévy's zebra Cranium, complete skeleton, left forefoot frontal, left forefoot side
Skeleton of a Grévy's zebra at theState Museum of Natural History Karlsruhe

As with all wild equines, zebras have barrel-chested bodies withtufted tails, elongated faces and long necks with long, erectmanes. Their thin legs are each supported by a spade-shaped toe covered in a hardhoof. Theirdentition is adapted forgrazing; they have large incisors that clip grass blades and rough molars and premolars well suited for grinding. Males have spade-shaped canines, which can be used as weapons in fighting. The eyes of zebras are at the sides and far up the head, which allows them to look over the tall grass while feeding. Their moderately long, erect ears are movable and can locate the source of a sound.[9][29][35]

Unlike horses, zebras and asses havechestnut callosities present only on their front legs. In contrast to other living equines, zebras have longer front legs than back legs.[35] Diagnostic traits of the zebra skull include: its relatively small size with a straight dorsal outline, protruding eye sockets, narrower rostrum, less conspicuouspostorbital bar, separation of themetaconid andmetastylid of the tooth by a V-shaped canal and roundedenamel wall.[42]

Stripes

"Zebra stripes" redirects here. For other uses, seeZebra stripes (disambiguation).
An illustration showing the three living zebra species
Comparative illustration of living zebra species

Zebras are easily recognised by their bold black-and-white striping patterns. Thecoat appears to be white with black stripes, as indicated by the belly and legs when unstriped, but the skin is black.[43][44][45] Young orfoals are born with brown and white coats, and the brown darkens with age.[28][25] Adorsal stripe acts as the backbone for vertical stripes along the sides, from the head to the rump. On the snout they curve toward the nostrils, while the stripes above the front legs split into two branches. On the rump, they develop into species-specific patterns. The stripes on the legs, ears and tail are separate and horizontal.[43]

Striping patterns are unique to an individual and heritable.[46] Duringembryonic development, the stripes appear at eight months, but the patterns may be determined at three to five weeks. For each species there is a point in embryonic development where the stripes are perpendicular to the dorsal line and spaced 0.4 mm (0.016 in) apart. However, this happens at three weeks of development for the plains zebra, four weeks for the mountain zebra, and five for Grévy's zebra. The difference in timing is thought to be responsible for the differences in the striping patterns of the different species.[43]

Various abnormalities of the patterns have been documented in plains zebras. In "melanistic" zebras, dark stripes are highly concentrated on the torso but the legs are whiter. "Spotted" individuals have broken up black stripes around the dorsal area.[47] There have even beenmorphs with white spots on dark backgrounds.[48] Striping abnormalities have been linked toinbreeding.[47]Albino zebras have been recorded in the forests ofMount Kenya, with the dark stripes being blonde.[49] The quagga had brown and white stripes on the head and neck, brown upper parts and a white belly, tail and legs.[50]

Function

The function of stripes in zebras has been discussed among biologists since at least the 19th century.[51] Popular hypotheses include the following:

  • Thecrypsis hypothesis suggests that the stripes allow the animal to blend in with its environment orbreak up its outline. This was the earliest hypothesis and proponents argued that the stripes were particularly suited for camouflage in tall grassland and woodland habitat.Alfred Wallace also wrote in 1896 that stripes make zebras less noticeable at night. BiologistTim Caro notes that zebras graze in open habitat and do not behave cryptically, being noisy, fast, and social and do not freeze when a predator is near. In addition, the camouflaging stripes of woodland living ungulates likebongos andbushbucks are much less vivid with less contrast with the background colour.[52] A 1987Fourier analysis study concluded that thespatial frequencies of zebra stripes do not line up with their environment,[53] while a 2014 study of wild equine species and subspecies could not find any correlations between striping patterns and woodland habitats.[54] Melin and colleagues (2016) found thatlions and hyenas do not appear to perceive the stripes when they are a certain distance away at daytime or nighttime, thus making the stripes useless in blending in except when the predators are close enough by which they could smell or hear their target. They also found that the stripes do not make the zebra less noticeable than solidly coloured herbivores on the open plains. They suggested that stripes may give zebras an advantage in woodlands, as the dark stripes could line up with the outlines of tree branches and other vegetation.[55]
Closeup shot of mountain zebra stripes
Closeup of mountain zebra stripes
  • Theconfusion hypothesis states that the stripes confuse predators, be it by: making it harder to distinguish individuals in a group as well as determining the number of zebras in a group; making it difficult to determine an individual's outline when the group runs away; reducing a predator's ability to keep track of a target during a chase;dazzling an assailant so they have difficulty making contact; or making it difficult for a predator to deduce the zebra's size, speed and direction viamotion dazzle. This theory has been proposed by several biologists since at least the 1970s.[56] A 2014 computer study of zebra stripes found that they may create awagon-wheel effect and/orbarber pole illusion when in motion. The researchers concluded that this could be used against mammalian predators or biting flies.[57] The use of the stripes for confusing mammalian predators has been questioned. Caro suggests that the stripes of zebras could make groups seem smaller, and thus more likely to be attacked. Zebras also tend to scatter when fleeing from attackers and thus the stripes could not break up an individual's outline. Lions, in particular, appear to have no difficulty targeting and catching zebras when they get close and take them by ambush.[58] In addition, no correlations have been found between the number of stripes and populations of mammal predators.[54] Hughes and colleagues (2021) disputed the idea of motion dazzle and concluded that moving objects that are solidly grey or have less contrasted patterns are actually more likely to escape being caught.[59]
  • Theaposematic hypothesis suggests that the stripes serve as warning colouration. This hypothesis was first suggested by Wallace in 1867 and discussed in more detail byEdward Bagnall Poulton in 1890. As with known aposematic mammals, zebras are recognizable up close, live in more open environments, have a high risk of predation and do not hide or act inconspicuous. However, Caro notes that stripes do not work on lions because they frequently prey on zebras, though they may work on smaller predators, and zebras are not slow-moving enough to need to ward off threats. In addition, zebras do not possess adequate defenses to back up the warning pattern.[60]
  • Thesocial function hypothesis states that stripes serve a role in intraspecific or individual recognition, social bonding, mutual grooming or a signal offitness.Charles Darwin wrote in 1871[a] that "a female zebra would not admit the addresses of a male ass until he was painted so as to resemble a zebra" while Wallace stated in 1871 that: "The stripes therefore may be of use by enabling stragglers to distinguish their fellows at a distance". Regarding species and individual identification, Caro notes that zebra species have limited range overlap with each other and horses can recognise each other using visual communication.[61] In addition, no correlation has been found between striping and social behaviour or group numbers among equines,[54] and no link has been found between fitness and striping.[62]
  • Thethermoregulatory hypothesis suggests that stripes help to control a zebra's body temperature. In 1971, biologist H. A. Baldwin noted that heat would be absorbed by the black stripes and reflected by the white ones and in 1990, zoologistDesmond Morris suggested that the stripes create coolingconvection currents.[63] A 2019 study supported this, finding that where the faster air currents of the warmer black stripes meet those of the white,air swirls form. The researchers also concluded that during the hottest times of the day, zebraserect their black hair to release heat from the skin and flatten it again when it gets cooler.[64] Larison and colleagues (2015) determined that environmental temperature is a strong predictor for zebra striping patterns.[65] Others have found no evidence that zebras have lower body temperatures than other ungulates whose habitat they share, or that striping correlates with temperature.[66][54] A 2018 experimental study which dressed water-filled metal barrels in horse, zebra and cattle hides concluded that the zebra stripes had no effect on thermoregulation.[67]
Comparison of horse fly flight patterns on horses and zebras
Comparison of flight patterns and contact/landings of horse flies around domestic horses (a-c) and plains zebras (d-f).[68]
  • Thefly protection hypothesis holds that the stripes deterblood-sucking flies.Horse flies, in particular, spread diseases that are lethal to equines such asAfrican horse sickness,equine influenza,equine infectious anemia andtrypanosomiasis. In addition, zebra hair is about as long as the mouthparts of these flies.[54] This hypothesis is the most strongly supported by the evidence.[68][69] It was found that flies preferred landing on solidly coloured surfaces over those with black-and-white striped patterns in 1930 by biologist R. Harris,[70] and this was proposed to have been a function of zebra stripes in a 1981 study.[71] A 2014 study found a correlation between striping and overlap with horse andtsetse fly populations and activity.[54] Other studies have found that zebras are rarely targeted by these insect species.[72] Caro and colleagues (2019) studied captive zebras and horses and observed that neither could deter flies from a distance, but zebra stripes kept flies from landing, both on zebras and horses dressed in zebraprint coats.[68] There does not appear to be any difference in the effectiveness of repelling flies between the different zebra species; thus the difference in striping patterns may have evolved for other reasons.[69] White or light stripes painted on dark bodies have also been found to reduce fly irritations in both cattle and humans.[73][74] How the stripes repel flies is less clear.[69] A 2012 study concluded that they disrupt thepolarised light patterns these insects use to locate water and habitat,[75] though subsequent studies have refuted this.[76][77][78] Stripes do not appear to work like a barber pole against flies sincecheckered patterns also repel them.[76][79] There is also little evidence that zebra stripes confuse the insects via visual distortion oraliasing.[76] Takács and colleagues (2022) suggest that, when the animal is in sunlight, temperature gradients between the warmer dark stripes and cooler white stripes prevent horseflies from detecting the warm blood vessels underneath.[77] Caro and colleagues (2023) conclude that the high colour contrast and relative thinness of the patterns make it difficult for the insects to find a place to land.[76]

Behaviour and ecology

Mountain zebra dust bathing
Mountain zebra dustbathing inNamibia

Zebras may travel ormigrate to wetter areas during the dry season.[28][29] Plains zebras have been recorded travelling 500 km (310 mi) between Namibia and Botswana, the longest land migration of mammals in Africa.[80] When migrating, they appear to rely on some memory of the locations where foraging conditions were best and may predict conditions months after their arrival.[81] Plains zebras are more water-dependent and live inmoister environments than other species. They usually can be found 10–12 km (6.2–7.5 mi) from a water source.[28][29][31] Grévy's zebras can survive almost a week without water but will drink it every day when given the chance, and their bodies maintain water better than cattle.[82][25] Mountain zebras can be found at elevations of up to 2,000 m (6,600 ft).[83] Zebras sleep up to seven hours a day, standing up during the day and lying down during the night. They regularly use various objects as rubbing posts and willroll on the ground.[29]

Plains zebras drinking at a river
Plains zebras atOkavango Delta,Botswana

A zebra's diet is mostlygrasses andsedges, but they will opportunistically consumebark, leaves, buds, fruits, and roots. Compared toruminants, zebras have a simpler and less efficient digestive system. Nevertheless, they can subsist on lower-quality vegetation. Zebras may spend 60–80% of their time feeding, depending on the availability of vegetation.[9][29] The plains zebra is a pioneer grazer, mowing down the upper, less nutritious grass canopy and preparing the way for more specialised grazers likewildebeest, which depend on shorter and more nutritious grasses below.[84]

Zebras are preyed on mainly by lions.Leopards,cheetahs,spotted hyenas,brown hyenas andwild dogs pose less of a threat to adults.[85] Biting and kicking are a zebra's defense tactics. When threatened by lions, zebras flee, and when caught they are rarely effective in fighting off the big cats.[86] In one study, the maximum speed of a zebra was found to be 50 km/h (31 mph) while a lion was measured at 74 km/h (46 mph). Zebras do not escape lions by speed alone but by sideways turning, especially when the cat is close behind.[87] With smaller predators like hyenas and dogs, zebras may act more aggressively, especially in defense of their young.[88]

Social behaviour

See also:Horse behaviour
A group of six plains zebra
A plains zebra group

Zebra species have two basic social structures. Plains and mountain zebras live in stable, closed family groups orharems consisting of onestallion, severalmares, and their offspring. These groups have their ownhome ranges, which overlap, and they tend to be nomadic. Stallions form and expand their harems by herding young mares away from their birth harems. The stability of the group remains even when the family stallion is displaced. Plains zebras groups gather into large herds and may create temporarily stable subgroups within a herd, allowing individuals to interact with those outside their group. Females in harems can spend more time feeding, and gain protection both for them and their young. They have a lineardominance hierarchy with the high-ranking females having lived in the group longest. While traveling, the most dominant females and their offspring lead the group, followed by the next most dominant; the family stallion trails behind. Young of both sexes leave their natal groups as they mature; females are usually herded by outside males to become part of their harems.[9][29][89]

In the more arid-living Grévy's zebras, adults have more fluid associations and adult males establish largeterritories, marked by dung piles, and mate with the females that enter them.[29][9] Grazing and drinking areas tend to be separated in these environments and the most dominant males establish territories near watering holes, which attract females with dependent foals and those who simply want a drink, while less dominant males control territories away from water with more vegetation, and only attract mares without foals.[90] Mares may travel through several territories but remain in one when they have young. Staying in a territory offers a female protection from harassment by outside males, as well as access to resources.[89][91]

Three Grévy's zebras grazing
Group of Grévy's zebras grazing

In all species, excess males gather inbachelor groups. These are typically young males that are not yet ready to establish a harem or territory.[9][29] With the plains zebra, the oldest males are the most dominant and group membership is stable.[29] Bachelor groups tend to be at the boundaries of herds and during group movements, the bachelors follow behind or along the sides.[31] Mountain zebra bachelor groups may also include young females that have left their natal group early, as well as old, former harem males. A territorial Grévy's zebra stallion may allow non-territorial bachelors in their territory, however when a mare inoestrous is present the territorial stallion keeps other stallions at bay. Bachelors prepare for their future harem roles with play fights and greeting/challenge rituals, which make up most of their activities.[29]

Fights between males usually occur over mates and involve biting and kicking. In plains zebra, stallions fight each other over recently matured mares to bring into their group and her father will fight off all suitors trying to abduct her. As long as a harem stallion is healthy, he is not usually challenged. Only unhealthy stallions have their harems taken over, and even then, the new stallion slowly takes over, peacefully displacing the old one.Agonistic behaviour between male Grévy's zebras occurs at the border of their territories.[29]

Communication

A pair of Plains zebra facing each other and rubbing heads on the others body
Plains zebras mutually grooming

Zebras produce a number of vocalisations and noises. The plains zebra has a distinctive,barking contact call heard as "a-ha, a-ha, a-ha" or "kwa-ha, kaw-ha, ha, ha".[28][29] The mountain zebra may produce a similar sound while the call of Grévy's zebra has been described as "something like ahippo's grunt combined with a donkey's wheeze". Loud snorting and rough "gasping" in zebras signals alarm. Squealing is usually made when in pain, but can also be heard in friendly interactions. Zebras also communicate with visual displays, and the flexibility of their lips allows them to make complex facial expressions. Visual displays also consist of head, ear, and tail postures. A zebra may signal an intention to kick by dropping back its ears and whipping its tail. Flattened ears, bared teeth and a waving head may be used as threatening gestures by stallions.[29]

Individuals may greet each other by mutually touching and rubbing, sniffing their genitals and resting their heads on their shoulders. They then may caress their shoulders against each other and lay their heads on one another. This greeting usually occurs between harem or territorial males or among bachelor males playing.[29] Plains and mountain zebras strengthen their social bonds withgrooming. Members of a harem nibble and rake along the neck, shoulder, and back with their teeth and lips. Grooming usually occurs between mothers and foals and between stallions and mares. Grooming establishes social rank and eases aggressive behaviour,[29][92] although Grévy's zebras generally do not perform social grooming.[25]

Reproduction and parenting

See also:Horse breeding
A pair of Grévy's zebras mating
Captive Grévy's zebras mating

Among plains and mountain zebras, the adult females mate only with their harem stallion, while in Grévy's zebras, mating is morepolygynandrous and the males have larger testes forsperm competition.[90][93] Female zebras have five to ten day long oestrous cycles; physical signs include a swollen, everted (inside out) labia and copious flows of urine and mucus. Upon reaching peak oestrous, mares spread-out their legs, lift their tails and open their mouths when in the presence of a male. Males assess the female's reproductive state with a curled lip and bared teeth (flehmen response) and the female will solicit mating by backing in. Gestation is typically around a year. A few days to a month later, mares can return to oestrus.[29] In harem-holding species, oestrus in a female becomes less noticeable to outside males as she gets older, hence competition for older females is virtually nonexistent.[28]

Mountain zebra suckling a foal
Mountain zebra suckling a foal

Usually, a single foal is born, which is capable of running within an hour of birth.[9] A newborn zebra will follow anything that moves, so new mothers prevent other mares from approaching their foals as they become more familiar with the mother's striping pattern, smell and voice.[25] At a few weeks old, foals begin to graze, but may continue to nurse for eight to thirteen months.[9] Living in an arid environment, Grévy's zebras have longer nursing intervals and young only begin to drink water three months after birth.[94]

In plains and mountain zebras, foals are cared for mostly by their mothers, but if threatened by pack-hunting hyenas and dogs, the entire group works together to protect all the young. The group forms a protective front with the foals in the centre, and the stallion will rush at predators that come too close.[29] In Grévy's zebras, young stay in "kindergartens" when their mothers leave for water. These groups are tended to by the territorial male.[94] A stallion may look after a foal in his territory to ensure that the mother stays, though it may not be his.[89] By contrast, plains zebra stallions are generally intolerant of foals that are not theirs and may practiceinfanticide andfeticide via violence to the pregnant mare.[95]

Human relations

Cultural significance

San rock art depicting a zebra
San rock art depicting a zebra

With their distinctive black-and-white stripes, zebras are among the most recognizable mammals. They have been associated with beauty and grace, with naturalistThomas Pennant describing them in 1781 as "the most elegant of quadrupeds". Zebras have been popular in photography, with some wildlife photographers describing them as the most photogenic animal. They have become staples in children's stories and wildlife-themed art, such as depictions ofNoah's Ark. In children'salphabet books, the animals are often used to represent the letter 'Z'. Zebra stripe patterns are popularly used for body paintings, dress, furniture and architecture.[96]

Zebras have been featured inAfrican art andculture for millennia. They are depicted inrock art in Southern Africa dating from 28,000 to 20,000 years ago, though less often than antelope species likeeland. How the zebra got its stripes has been the subject offolk tales, some of which involve it being scorched by fire. TheMaasai proverb "a man without culture is like a zebra without stripes" has become popular in Africa. TheSan people connected zebra stripes with water, rain and lightning, andwater spirits were conceived of having these markings.[97]

Illustration of a business's "Zebra Stripes" logo
"Zebra Stripes," trademark for the defunctGlen Raven Cotton Mills Company

For theShona people, the zebra is atotem animal and is glorified in a poem as an "iridescent and glittering creature". Its stripes have symbolised the union of male and female and at the ruined city ofGreat Zimbabwe, zebra stripes decorate what is believed to be adomba, a school meant to prepare girls for adulthood. In theShona language, the namemadhuve means "woman/women of the zebra totem" and is a name for girls inZimbabwe. The plains zebra is thenational animal of Botswana and zebras have been depicted on stamps duringcolonial and post-colonial Africa. For people of theAfrican diaspora, the zebra represented the politics of race and identity, being both black and white.[98]

In cultures outside of its range, the zebra has been thought of as a more exotic alternative to the horse; the comic book characterSheena, Queen of the Jungle, is depicted riding a zebra and explorerOsa Johnson was photographed riding one. The filmRacing Stripes features a captive zebra ostracised from the horses and ends up being ridden by a rebellious girl. Zebras have been featured as characters in animated films likeKhumba,The Lion King and theMadagascar films and television series such asZou.[99]

Zebras have been popular subjects forabstract,modernist andsurrealist artists. Such art includesChristopher Wood'sZebra and Parachute,Lucian Freud'sThe Painter's Room andQuince on a Blue Table and the various paintings ofMary Fedden andSidney Nolan.Victor Vasarely depicted zebras as black and white lines and connected in ajigsaw puzzle fashion.Carel Weight'sEscape of the Zebra from the Zoo during an Air Raid was based on a real life incident of a zebra escaping duringthe bombing of London Zoo and consists of four comic book-like panels. Zebras have lent themselves to products and advertisements, including for 'Zebra Grate Polish' cleaning supplies by British manufacturerReckitt and Sons and Japanese pen manufacturerZebra Co., Ltd.[100]

Captivity

A portrait of a zebra by George Stubbs
Zebra (1763) byGeorge Stubbs. A portrait ofQueen Charlotte's zebra

Zebras have been kept in captivity since at least theRoman Empire. In later times, captive zebras have been shipped around the world, often for diplomatic reasons. In 1261, SultanBaibars ofEgypt established an embassy withAlfonso X of Castile and sent a zebra and other exotic animals as gifts. In 1417, a zebra was gifted to the Chinese people by Somalia and displayed before theYongle Emperor. The fourthMughal emperorJahangir received a zebra from Ethiopia in 1620 andUstad Mansur made a painting of it. In the 1670s,Ethiopian EmperorYohannes I exported two zebras to the Dutch governor ofJakarta. These animals would eventually be given by the Dutch to theTokugawa Shogunate of Japan.[101]

WhenQueen Charlotte received a zebra as a wedding gift in 1762, the animal became a source of fascination for the people of Britain. Many flocked to see it at itspaddock atBuckingham Palace. It soon became the subject of humour and satire, being referred to as "The Queen's Ass", and was the subject of an oil painting byGeorge Stubbs in 1763. The zebra also gained a reputation for being ill-tempered and kicked at visitors.[102] In 1882, Ethiopia sent a zebra to French presidentJules Grévy, and the species it belonged to was named in his honour.[10]

Walter Rothschild with a carriage drawn by four zebra
Walter Rothschild with a zebra carriage

Attempts todomesticate zebras were largely unsuccessful. It is possible that having evolved under pressure from the many large predators of Africa, including early humans, they became more aggressive, thus making domestication more difficult.[103] However, zebras have beentrained throughout history. In Rome, zebras are recorded to have pulled chariots duringamphitheatre games starting in the reign ofCaracalla (198 to 217 AD).[104] In the late 19th century, the zoologistWalter Rothschild trained some zebras to draw a carriage in England, which he drove to Buckingham Palace to demonstrate that it can be done. However, he did not ride on them knowing that they were too small and aggressive.[105] In the early 20th century,German colonial officers in East Africa tried to use zebras for both driving and riding, with limited success.[106]

Conservation

Mountain zebra hide
Mountain zebra hide

As of 2016–2019, theIUCN Red List of mammals lists Grévy's zebra asendangered, the mountain zebra asvulnerable and the plains zebra asnear-threatened. Grévy's zebra populations are estimated at less than 2,000 mature individuals, but they are stable. Mountain zebras number near 35,000 individuals and their population appears to be increasing. Plains zebra are estimated to number 150,000–250,000 with a decreasing population trend. Human intervention has fragmented zebra ranges and populations. Zebras are threatened by hunting for their hide and meat, andhabitat destruction. They also compete with livestock and have their travelling routes obstruct by fences.[107][108][109] Civil wars in some countries have also caused declines in zebra populations.[110] By the early 20th century, zebra skins were being used to make rugs and chairs. In the 21st century, zebras may be taken bytrophy hunters as zebra skin rugs sell for $1,000 to $2,000. Trophy hunting was rare among African peoples though the San were known to hunt zebra for meat.[111]

A herd of Grévy's zebras in Samburu National Reserve
Endangered Grévy's zebras inSamburu National Reserve

Thequagga (E. quagga quagga) population was hunted by early Dutch settlers and later byAfrikaners to provide meat or for their skins. The skins were traded or used locally. The quagga was probably vulnerable to extinction due to its restricted range, and because they were easy to find in large groups. The last known wild quagga died in 1878.[112] The last captive quagga, a female in Amsterdam'sNatura Artis Magistra zoo, lived there from 9 May 1867 until it died on 12 August 1883.[113] TheCape mountain zebra, a subspecies of mountain zebra, nearly went extinct due to hunting and habitat destruction, with less than 50 individuals left by the 1950s. Protections fromSouth African National Parks allowed the population to rise to 2,600 by the 2010s.[114]

Zebras can be found in numerous protected areas. Important areas for Grévy's zebra includeYabelo Wildlife Sanctuary andChelbi Sanctuary in Ethiopia andBuffalo Springs,Samburu andShaba National Reserves inKenya.[107] The plains zebra inhabits theSerengeti National Park in Tanzania,Tsavo andMasai Mara in Kenya,Hwange National Park in Zimbabwe,Etosha National Park inNamibia, andKruger National Park inSouth Africa.[109] Mountain zebras are protected inMountain Zebra National Park,Karoo National Park andGoegap Nature Reserve in South Africa as well as Etosha andNamib-Naukluft Park in Namibia.[108][115]

Notes

  1. ^The cited source cites the 1896 edition of Darwin's 1871 bookThe Descent of Man, and Selection in Relation to Sex.

See also

References

  1. ^abBadenhorst, S.; Steininger, C. M. (2019)."The Equidae from Cooper's D, an early Pleistocene fossil locality in Gauteng, South Africa".PeerJ.7 e6909.doi:10.7717/peerj.6909.PMC 6525595.PMID 31143541.
  2. ^Wells, John C. (2008).Longman Pronunciation Dictionary (3rd ed.). Longman.ISBN 978-1-4058-8118-0.
  3. ^"Zebra".Online Etymology Dictionary. Retrieved22 June 2020.
  4. ^"Zebra".Lexico. Archived fromthe original on 27 June 2020. Retrieved25 June 2020.
  5. ^abNores, Carlos; Muñiz, Arturo Morales; Rodríguez, Laura Llorente; Bennett, E. Andrew; Geigl, Eva-María (2015)."The Iberian Zebro: what kind of a beast was it?".Anthropozoologica.50:21–32.doi:10.5252/az2015n1a2.hdl:10651/34413.S2CID 55004515.
  6. ^Plumb & Shaw 2018, p. 54.
  7. ^Wells, John (1997)."Our Changing Pronunciation".Transactions of the Yorkshire Dialect Society.XIX:42–48.Archived from the original on 7 October 2014. Retrieved6 February 2014.
  8. ^"Zebra".Cambridge Dictionary. Retrieved26 May 2020.
  9. ^abcdefghijklRubenstein, D. I. (2001). "Horse, Zebras and Asses". In MacDonald, D. W. (ed.).The Encyclopedia of Mammals (2nd ed.).Oxford University Press. pp. 468–473.ISBN 978-0-7607-1969-5.
  10. ^abProthero, D. R.; Schoch, R. M. (2003).Horns, Tusks, and Flippers: The Evolution of Hoofed Mammals.Johns Hopkins University Press. pp. 216–218.ISBN 978-0-8018-7135-1.
  11. ^"Hippotigris".ITIS. Retrieved31 August 2020.
  12. ^"Dolichohippus".ITIS. Retrieved31 August 2020.
  13. ^abGroves, C. P.; Bell, C. H. (2004). "New investigations on the taxonomy of the zebras genusEquus, subgenusHippotigris".Mammalian Biology.69 (3):182–196.Bibcode:2004MamBi..69..182G.doi:10.1078/1616-5047-00133.
  14. ^abcVilstrup, Julia T.; Seguin-Orlando, A.; Stiller, M.; Ginolhac, A.; Raghavan, M.; Nielsen, S. C. A.; et al. (2013)."Mitochondrial phylogenomics of modern and ancient equids".PLoS One.8 (2) e55950.Bibcode:2013PLoSO...855950V.doi:10.1371/journal.pone.0055950.PMC 3577844.PMID 23437078.
  15. ^Groves, C.; Grubb, P. (2011).Ungulate Taxonomy. Johns Hopkins University Press. p. 16.ISBN 978-1-4214-0093-8.
  16. ^Hofreiter, M.; Caccone, A.; Fleischer, R. C.; Glaberman, S.; Rohland, N.; Leonard, J. A. (2005)."A rapid loss of stripes: The evolutionary history of the extinct quagga".Biology Letters.1 (3):291–295.doi:10.1098/rsbl.2005.0323.PMC 1617154.PMID 17148190.
  17. ^abPedersen, Casper-Emil T.; Albrechtsen, Anders; Etter, Paul D.; Johnson, Eric A.; Orlando, Ludovic; Chikhi, Lounes; Siegismund, Hans R.; Heller, Rasmus (2018). "A southern African origin and cryptic structure in the highly mobile plains zebra".Nature Ecology & Evolution.2 (3):491–498.Bibcode:2018NatEE...2..491P.doi:10.1038/s41559-017-0453-7.ISSN 2397-334X.PMID 29358610.S2CID 3333849.
  18. ^Forstén, Ann (1992)."Mitochondrial-DNA timetable and the evolution ofEquus: of molecular and paleontological evidence"(PDF).Annales Zoologici Fennici.28:301–309.
  19. ^Ryder, O. A.; George, M. (1986)."Mitochondrial DNA evolution in the genusEquus"(PDF).Molecular Biology and Evolution.3 (6):535–546.doi:10.1093/oxfordjournals.molbev.a040414.PMID 2832696. Archived fromthe original(PDF) on 28 May 2016. Retrieved13 November 2015.
  20. ^Orlando, L.; Ginolhac, A.; Zhang, G.; Froese, D.; Albrechtsen, A.; Stiller, M.; et al. (July 2013). "Recalibrating Equus evolution using the genome sequence of an early Middle Pleistocene horse".Nature.499 (7456):74–78.Bibcode:2013Natur.499...74O.doi:10.1038/nature12323.PMID 23803765.S2CID 4318227.
  21. ^abJónsson, Hákon; Schubert, Mikkel; Seguin-Orlando, Andaine; Orlando, Ludovic (2014)."Speciation with gene flow in equids despite extensive chromosomal plasticity".Proceedings of the National Academy of Sciences.111 (52):18655–18660.Bibcode:2014PNAS..11118655J.doi:10.1073/pnas.1412627111.PMC 4284605.PMID 25453089.
  22. ^Druzhkova, Anna S.; Makunin, Alexey I.; Vorobieva, Nadezhda V.; Vasiliev, Sergey K.; Ovodov, Nikolai D.; Shunkov, Mikhail V.; Trifonov, Vladimir A.; Graphodatsky, Alexander S. (January 2017)."Complete mitochondrial genome of an extinctEquus (Sussemionus) ovodovi specimen from Denisova cave (Altai, Russia)".Mitochondrial DNA Part B.2 (1):79–81.doi:10.1080/23802359.2017.1285209.ISSN 2380-2359.PMC 7800821.PMID 33473722.
  23. ^Cai, Dawei; Zhu, Siqi; Gong, Mian; Zhang, Naifan; Wen, Jia; Liang, Qiyao; Sun, Weilu; Shao, Xinyue; Guo, Yaqi; Cai, Yudong; Zheng, Zhuqing; Zhang, Wei; Hu, Songmei; Wang, Xiaoyang; Tian, He (11 May 2022)."Radiocarbon and genomic evidence for the survival of Equus Sussemionus until the late Holocene".eLife.11 e73346.doi:10.7554/eLife.73346.ISSN 2050-084X.PMC 9142152.PMID 35543411.
  24. ^abcCaro 2016, p. 9.
  25. ^abcdefgChurcher, C. S. (1993)."Equus grevyi"(PDF).Mammalian Species (453):1–9.doi:10.2307/3504222.JSTOR 3504222.
  26. ^Caro 2016, p. 15.
  27. ^abcdCaro 2016, p. 14.
  28. ^abcdefGrubb, P. (1981)."Equus burchellii".Mammalian Species (157):1–9.doi:10.2307/3503962.JSTOR 3503962.
  29. ^abcdefghijklmnopqrEstes, R. (1991).The Behavior Guide to African Mammals.University of California Press. pp. 235–248.ISBN 978-0-520-08085-0.
  30. ^Caro 2016, pp. 12–13.
  31. ^abcdSkinner, J. D.; Chimimba, C. T. (2005). "Equidae".The Mammals of the Southern African Subregion (3rd ed.).Cambridge University Press. pp. 541–546.ISBN 978-0-521-84418-5.
  32. ^abCaro 2016, p. 11.
  33. ^Caro 2016, p. 13.
  34. ^abcPenzhorn, B. L. (1988). "Equus zebra".Mammalian Species (314):1–7.doi:10.2307/3504156.JSTOR 3504156.S2CID 253987177.
  35. ^abcRubenstein, D. I. (2011). "Family Equidae: Horses and relatives". In Wilson, D. E.; Mittermeier, R. A.; Llobet, T. (eds.).Handbook of the Mammals of the World. Vol. 2: Hoofed Mammals (1st ed.).Lynx Edicions. pp. 106–111.ISBN 978-84-96553-77-4.
  36. ^abChurcher, C. S. (2006). "Distribution and history of the Cape zebra (Equus capensis) in the Quarternary of Africa".Transactions of the Royal Society of South Africa.61 (2):89–95.Bibcode:2006TRSSA..61...89C.doi:10.1080/00359190609519957.S2CID 84203907.
  37. ^Azzaroli, A.; Stanyon, R. (1991). "Specific identity and taxonomic position of the extinct Quagga".Rendiconti Lincei.2 (4): 425.doi:10.1007/BF03001000.S2CID 87344101.
  38. ^Eisenmann, V. (2008)."Pliocene and Pleistocene equids: palaeontology versus molecular biology".Courier Forschungsinstitut Senckenberg.256:71–89.
  39. ^Cordingley, J. E.; Sundaresan, S. R.; Fischhoff, I. R.; Shapiro, B.; Ruskey, J.; Rubenstein, D. I. (2009). "Is the endangered Grevy's zebra threatened by hybridization?".Animal Conservation.12 (6):505–513.Bibcode:2009AnCon..12..505C.doi:10.1111/j.1469-1795.2009.00294.x.S2CID 18388598.
  40. ^Giel, E.-M.; Bar-David, S.; Beja-Pereira, A.; Cothern, E. G.; Giulotto, E.; Hrabar, H.; Oyunsuren, T.; Pruvost, M. (2016). "Genetics and Paleogenetics of Equids". In Ransom, J. I.; Kaczensky, P. (eds.).Wild Equids: Ecology, Management, and Conservation. Johns Hopkins University Press. p. 99.ISBN 978-1-4214-1909-1.
  41. ^Bittel, Jason (19 June 2015)."Hold Your Zorses: The sad truth about animal hybrids".Slate.com. Retrieved16 May 2020.
  42. ^Badam, G. L.; Tewari, B. S. (1974). "On the zebrine affinities of the Pleistocene horseEquus sivalensis,falconer andcautley".Bulletin of the Deccan College Post-Graduate and Research Institute.34 (1/4):7–11.JSTOR 42931011.
  43. ^abcBard, J. (1977). "A unity underlying the different zebra patterns".Journal of Zoology.183 (4):527–539.doi:10.1111/j.1469-7998.1977.tb04204.x.
  44. ^Langley, Liz (4 March 2017)."Do Zebras Have Stripes On Their Skin?".National Geographic. Archived fromthe original on 1 August 2020. Retrieved2 June 2020.
  45. ^Caro 2016, pp. 14–15.
  46. ^Caro 2016, pp. 7, 19.
  47. ^abLarison, Brenda; Kaelin, Christopher B.; Harrigan, Ryan; et al. (2020). "Population structure, inbreeding and stripe pattern abnormalities in plains zebras".Molecular Ecology.30 (2):379–390.doi:10.1111/mec.15728.PMID 33174253.S2CID 226305574.
  48. ^Caro 2016, p. 20.
  49. ^"Extremely Rare 'Blonde' Zebra Photographed".National Geographic. 29 March 2019. Archived fromthe original on 29 March 2019. Retrieved25 May 2020.
  50. ^Nowak, R. M. (1999).Walker's Mammals of the World. Vol. 1.Johns Hopkins University Press. pp. 1024–1025.ISBN 978-0-8018-5789-8.
  51. ^Caro 2016, p. 1.
  52. ^Caro 2016, pp. 2–3, 23, 48, 50.
  53. ^Godfrey, D.; Lythgoe, J. N.; Rumball, D. A. (1987). "Zebra stripes and tiger stripes: the spatial frequency distribution of the pattern compared to that of the background is significant in display and crypsis".Biological Journal of the Linnean Society.32 (4):427–433.doi:10.1111/j.1095-8312.1987.tb00442.x.
  54. ^abcdefCaro, T.; Izzo, A.; Reiner, R. C.; Walker, H.; Stankowich, T. (2014)."The function of zebra stripes".Nature Communications.5 3535.Bibcode:2014NatCo...5.3535C.doi:10.1038/ncomms4535.PMID 24691390.
  55. ^Melin, A. D.; Kline, D. W.; Hiramatsu, C; Caro, T (2016)."Zebra stripes through the eyes of their predators, zebras, and humans".PLOS ONE.11 (1) e0145679.Bibcode:2016PLoSO..1145679M.doi:10.1371/journal.pone.0145679.PMC 4723339.PMID 26799935.
  56. ^Caro 2016, pp. 72–81, 86.
  57. ^How, M. J.; Zanker, J. M. (2014). "Motion camouflage induced by zebra stripes".Zoology.117 (3):163–170.Bibcode:2014Zool..117..163H.doi:10.1016/j.zool.2013.10.004.PMID 24368147.
  58. ^Caro 2016, pp. 80, 92.
  59. ^Hughes, A. E.; Griffiths, D; Troscianko, J; Kelley, L. A. (2021)."The evolution of patterning during movement in a large-scale citizen science game".Proceedings of the Royal Society B: Biological Sciences.288 (1942) 20202823.doi:10.1098/rspb.2020.2823.PMC 7892415.PMID 33434457.
  60. ^Caro 2016, pp. 55, 57–58, 68.
  61. ^Caro 2016, pp. 6–7, 139–148, 150.
  62. ^Caro 2016, p. 150.
  63. ^Caro 2016, p. 7.
  64. ^Cobb, A.; Cobb, S. (2019). "Do zebra stripes influence thermoregulation?".Journal of Natural History.53 (13–14):863–879.Bibcode:2019JNatH..53..863C.doi:10.1080/00222933.2019.1607600.S2CID 196657566.
  65. ^Larison, Brenda; Harrigan, Ryan J.; Thomassen, Henri A.; Rubenstein, Daniel I.; Chan-Golston, Alec M.; Li, Elizabeth; Smith, Thomas B. (2015)."How the zebra got its stripes: a problem with too many solutions".Royal Society Open Science.2 (1) 140452.Bibcode:2015RSOS....240452L.doi:10.1098/rsos.140452.PMC 4448797.PMID 26064590.
  66. ^Caro 2016, pp. 158–161.
  67. ^Horváth, Gábor; Pereszlényi, Ádám; Száz, Dénes; Barta, András; Jánosi, Imre M.; Gerics, Balázs; Åkesson, Susanne (2018)."Experimental evidence that stripes do not cool zebras".Scientific Reports.8 (1): 9351.Bibcode:2018NatSR...8.9351H.doi:10.1038/s41598-018-27637-1.PMC 6008466.PMID 29921931.
  68. ^abcCaro, T.; Argueta, Y.; Briolat, E. S.; Bruggink, J.; Kasprowsky, M.; Lake, J.; Mitchell, M.; Richardson, S.; How, M. (2019)."Benefits of zebra stripes: behaviour of tabanid flies around zebras and horses".PLOS ONE.14 (2) e0210831.Bibcode:2019PLoSO..1410831C.doi:10.1371/journal.pone.0210831.PMC 6382098.PMID 30785882.
  69. ^abcTombak, K. J.; Gersick, A. S.; Reisinger, L. V.; Larison, B; Rubenstein, D. I. (2022)."Zebras of all stripes repel biting flies at close range".Scientific Reports.22 (18617): 18617.Bibcode:2022NatSR..1218617T.doi:10.1038/s41598-022-22333-7.PMC 9633588.PMID 36329147.
  70. ^Caro 2016, p. 5.
  71. ^Waage, J. K. (1981). "How the zebra got its stripes - biting flies as selective agents in the evolution of zebra coloration".Journal of the Entomological Society of Southern Africa.44 (2):351–358.hdl:10520/AJA00128789_3800.
  72. ^Caro 2016, pp. 196–197.
  73. ^Kojima, T.; Oishi, K.; Matsubara, Y.; Uchiyama, Y.; Fukushima, Y. (2020)."Cows painted with zebra-like striping can avoid biting fly attack".PLOS ONE.15 (3) e0231183.doi:10.1371/journal.pone.0231183.PMC 7098620.PMID 32214400.
  74. ^Horváth, G.; Pereszlényi, Á.; Åkesson, S.; Kriska, G. (2019)."Striped bodypainting protects against horseflies".Royal Society Open Science.6 (1) 181325.Bibcode:2019RSOS....681325H.doi:10.1098/rsos.181325.PMC 6366178.PMID 30800379.
  75. ^Egri, Ádám; Blahó, Miklós; Kriska, György; Farkas, Róbert; Gyurkovszky, Mónika; Åkesson, Susanne; Horváth, Gábor (2012)."Polarotactic tabanids find striped patterns with brightness and/or polarization modulation least attractive: an advantage of zebra stripes".Journal of Experimental Biology.215 (5):736–745.Bibcode:2012JExpB.215..736E.doi:10.1242/jeb.065540.PMID 22323196.
  76. ^abcdCaro, T; Fogg, E; Stephens-Collins, T; Santon, M; How, M. J. (2023)."Why don't horseflies land on zebras?".Journal of Experimental Biology.226 (4): jeb244778.Bibcode:2023JExpB.226B4778C.doi:10.1242/jeb.244778.PMC 10088525.PMID 36700395.S2CID 256273744.
  77. ^abTakács, P; Száz, D; Vincze, M; Slíz-Balogh, J; Horváth, G (2022)."Sunlit zebra stripes may confuse the thermal perception of blood vessels causing the visual unattractiveness of zebras to horseflies".Scientific Reports.12 (10871): 10871.Bibcode:2022NatSR..1210871T.doi:10.1038/s41598-022-14619-7.PMC 9352684.PMID 35927437.
  78. ^Britten, K. H.; Thatcher, T. D.; Caro, T (2016)."Zebras and biting flies: quantitative analysis of reflected light from zebra coats in Their natural habitat".PLOS ONE.11 (5) e0154504.Bibcode:2016PLoSO..1154504B.doi:10.1371/journal.pone.0154504.PMC 4880349.PMID 27223616.
  79. ^How, M. J.; Gonzales, D.; Irwin, A.; Caro, T. (2020)."Zebra stripes, tabanid biting flies and the aperture effect".Proceedings of the Royal Society B: Biological Sciences.287 (1933) 20201521.doi:10.1098/rspb.2020.1521.PMC 7482270.PMID 32811316.
  80. ^Naidoo, R.; Chase, M. J.; Beytall, P.; Du Preez, P. (2016)."A newly discovered wildlife migration in Namibia and Botswana is the longest in Africa".Oryx.50 (1):138–146.doi:10.1017/S0030605314000222.
  81. ^Bracis, C.; Mueller, T. (2017)."Memory, not just perception, plays an important role in terrestrial mammalian migration".Proceedings of the Royal Society B: Biological Sciences.284 (1855) 20170449.doi:10.1098/rspb.2017.0449.PMC 5454266.PMID 28539516.
  82. ^Youth, H. (November–December 2004)."Thin stripes on a thin line".Zoogoer.33. Archived fromthe original on 26 October 2005.
  83. ^Woodward, Susan L. (2008).Grassland Biomes.Greenwood Press. p. 49.ISBN 978-0-313-33999-8.
  84. ^Pastor, J.; Cohen, U.; Hobbs, T. (2006). "The roles of large herbivores in ecosystem nutrient cycles". In Danell, K. (ed.).Large Herbivore Ecology, Ecosystem Dynamics and Conservation.Cambridge University Press. p. 295.ISBN 978-0-521-53687-5.
  85. ^Caro 2016, pp. 61–63.
  86. ^Caro 2016, p. 61–62.
  87. ^Wilson, A.; Hubel, T.; Wilshin, S.; et al. (2018)."Biomechanics of predator–prey arms race in lion, zebra, cheetah and impala"(PDF).Nature.554 (7691):183–188.Bibcode:2018Natur.554..183W.doi:10.1038/nature25479.PMID 29364874.S2CID 4405091.
  88. ^Caro 2016, pp. 62–63.
  89. ^abcRubenstein, D. I. (1986). "Ecology and sociality in horses and zebras". In Rubenstein, D. I.; Wrangham, R. W. (eds.).Ecological Aspects of Social Evolution(PDF).Princeton University Press. pp. 282–302.ISBN 978-0-691-08439-8.
  90. ^abRubenstein, D. I. (2010). "Ecology, social behavior, and conservation in zebras". In Macedo, R.; Wrangham (eds.).Behavioral Ecology of Tropical Animals(PDF). Academic Press. pp. 231–258.ISBN 978-0-12-380894-3.
  91. ^Sundaresan, S. R.; Fischhoff, I. R.; Rubenstein, D. (2007)."Male harassment influences female movements and associations in Grevy's zebra (Equus grevyi)"(PDF).Behavioral Ecology.18 (5):860–65.doi:10.1093/beheco/arm055.
  92. ^Caro 2016, p. 143.
  93. ^Ginsberg, R; Rubenstein, D. I. (1990)."Sperm competition and variation in zebra mating behavior"(PDF).Behavioral Ecology and Sociobiology.26 (6):427–434.Bibcode:1990BEcoS..26..427G.doi:10.1007/BF00170901.S2CID 206771095.
  94. ^abBecker, C. D.; Ginsberg, J. R. (1990). "Mother-infant behaviour of wild Grevy's zebra".Animal Behaviour.40 (6):1111–1118.doi:10.1016/S0003-3472(05)80177-0.S2CID 54252836.
  95. ^Pluháček, J; Bartos, L (2005)."Further evidence for male infanticide and feticide in captive plains zebra,Equus burchelli"(PDF).Folia Zoologica-Praha.54 (3):258–262.
  96. ^Plumb & Shaw 2018, pp. 10–13, 40–41, 134–140, 189.
  97. ^Plumb & Shaw 2018, pp. 37–44.
  98. ^Plumb & Shaw 2018, pp. 45–50.
  99. ^Plumb & Shaw 2018, pp. 167–169, 188, 192–194, 200–201.
  100. ^Plumb & Shaw 2018, pp. 128–131, 141–149.
  101. ^Plumb & Shaw 2018, pp. 55–62, 65–66.
  102. ^Plumb & Shaw 2018, pp. 76–78, 81.
  103. ^"The Story Of... Zebra and the Puzzle of African Animals".PBS. Retrieved13 August 2020.
  104. ^Plumb & Shaw 2018, p. 56.
  105. ^Young, R. (23 May 2013)."Can Zebras Be Domesticated and Trained?".Slate. Retrieved4 September 2013.
  106. ^Gann, L.; Duignan, Peter (1977).The Rulers of German Africa, 1884–1914.Stanford University Press. p. 206.ISBN 978-0-8047-6588-6.
  107. ^abRubenstein, D.; Low Mackey, B.; Davidson, Z. D.; Kebede, F.; King, S. R. B. (2016)."Equus grevyi".IUCN Red List of Threatened Species.2016. Retrieved24 May 2020.
  108. ^abGosling, L. M.; Muntifering, J.; Kolberg, H.; Uiseb, K.; King, S. R. B. (2016)."Equus zebra".IUCN Red List of Threatened Species.2016. Retrieved24 May 2020.
  109. ^abKing, S. R. B.; Moehlman, P. D. (2016)."Equus quagga".IUCN Red List of Threatened Species.2016. Retrieved24 May 2020.
  110. ^Hack, Mace A.; East, Rod; Rubenstein, Dan J. (2002). "Status and Action Plan for the Plains Zebra (Equus burchelli)". In Moehlman, P. D. (ed.).Equids. Zebras, Asses and Horses. Status Survey and Conservation Action Plan. IUCN/SSC Equid Specialist Group. IUCN. p. 51.ISBN 978-2-8317-0647-4.
  111. ^Plumb & Shaw 2018, pp. 41, 132–133.
  112. ^Weddell, B. J. (2002).Conserving Living Natural Resources: In the Context of a Changing World.Cambridge University Press. p. 46.ISBN 978-0-521-78812-0.
  113. ^Van Bruggen, A. C. (1959). "Illustrated notes on some extinct South African ungulates".South African Journal of Science.55:197–200.
  114. ^Kotzé, A.; Smith, R. M.; Moodley, Y.; Luikart, G.; Birss, C.; Van Wyk, A. M.; Grobler, J. P.; Dalton, D. L. (2019)."Lessons for conservation management: Monitoring temporal changes in genetic diversity of Cape mountain zebra (Equus zebra zebra)".PLOS ONE.14 (7) e0220331.Bibcode:2019PLoSO..1420331K.doi:10.1371/journal.pone.0220331.PMC 6668792.PMID 31365543.
  115. ^Hamunyela, Elly (27 March 2017)."The status of Namibia's Hartmann's zebra". Travel News Namibia. Retrieved9 July 2020.

General bibliography

External links

Wikimedia Commons has media related toZebras.
Wikisource has the text of the1911Encyclopædia Britannica article "Zebra".
  • The Quagga Project—An organisation that selectively breeds zebras to recreate the hair coat pattern of the quagga
ExtantPerissodactyla(Odd-toed ungulates) species by suborder
Equidae
(Horse family)
Equus
(includingZebras)
Rhinocerotidae
(Rhinoceroses)
Rhinoceros
Dicerorhinus
Ceratotherium
Diceros
Tapiridae(Tapirs)
Tapirus
Species of the genusEquus
Extinct species are marked
Asses
African wild ass
(Equus africanus)
Onager / Asiatic wild ass
(Equus hemionus)
Kiang/Tibetan wild ass
(Equus kiang)
Horses
Wild horse (Equus ferus)
Zebras
Plains zebra (Equus quagga)
Mountain zebra (Equus zebra)
Grévy's zebra (Equus grevy)
Hybrids
Prehistoric
Equus species
Hippotigris
International
National
Other
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