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For other uses, see Giraffe (disambiguation).

Giraffe[1]
A Maasai giraffe in Mikumi National Park, Tanzania
Scientific classification
Kingdom:
Animalia
Phylum:
Chordata
Class:
Mammalia
Order:
Artiodactyla
Family:
Giraffidae
Genus:
Giraffa
Species:
G. camelopardalis
Binomial name
Giraffa camelopardalis
Subspecies

9, see text

Range map of the giraffe divided by subspecies.

The giraffe (Giraffa camelopardalis) is an African even-toed ungulate mammal, the tallest living terrestrial animal and the largest ruminant. Its specific name refers to its camel-like face and patches of color on a light background, which bear a vague resemblance to a leopard's spots. The giraffe is also noted for its extremely long neck and legs and prominent horns. It stands 5.8 m (19 ft) tall and has an average weight of 1,600 kg (3,500 lb) for males and 830 kg (1,830 lb) for females. It is classified under the family Giraffidae, along with its closest extant relative, the okapi. There are nine subspecies, which differ in size, coloration, pattern, and range.

The giraffe's scattered range extends from Chad in the north to South Africa in the south and from Niger in the west to Somalia in the east. Giraffes usually inhabit savannas, grasslands, and open woodlands. They prefer areas with plenty of acacia trees, which are important food sources, and can browse at heights that most other herbivores cannot reach. While adults are nearly invulnerable to predation, lions, leopards, spotted hyenas and wild dogs prey on calves. Giraffes commonly gather in aggregations that usually disband every few hours. Males establish social hierarchies through "neckings", which are combat bouts where the neck is used as a weapon. Dominant males gain mating access to females, who bear the sole responsibility for raising the young.

The giraffe has intrigued various cultures, both ancient and modern, for its peculiar appearance, and has often been featured in paintings, novels and cartoons. It is classified by the International Union for Conservation of Nature (IUCN) as Least Concern, but has been extirpated from many parts of its former range, and some subspecies are classified as Endangered. Nevertheless, giraffes are still found in numerous game reserves.

Etymology

The name giraffe has its earliest known origins in the Arabic word الزرافة al-zirāfah, perhaps from an African name. There were several Middle Eastern spellings such as jarraf, ziraph, and gerfauntz.[3] It is also possible that the word was derived from the animal's Somali name Geri.[4] 'The Italian form giraffa arose in the 1590s.[3] The modern English form developed around 1600 from the French girafe.[3] The species name camelopardalis is a Latin word,[5] a romanization of the Greek καμηλοπάρδαλις,[6] from κάμηλος (kamēlos), "camel",[7] + πάρδαλις (pardalis), "leopard".[8] Kameelperd is also the name for the species in Afrikaans.[9]

Other African names for the giraffe include Ekorii (Ateso), Kanyiet (Elgon), Nduida (Gikuyu), Tiga (Kalenjin and Luo), Ndwiya (Kamba), Nudululu (Kihehe), Ntegha (Kinyaturu), Ondere (Lugbara), Etiika (Luhya), Kuri (Ma'di), Oloodo-kirragata or Olchangito-oodo (Maasai), Lenywa (Meru), Hori (Pare), Lment (Samburu) and Twiga (Swahili and others) in the east;[10]: 313  and Tutwa (Lozi), Nthutlwa (Shangaan), Indlulamitsi (Siswati), Thutlwa (Sotho), Thuda (Venda) and Ndlulamithi (Zulu) in the south.[9]

Taxonomy and evolution

Mounted Shansitherium skeleton from the Beijing Museum of Natural History

The giraffe is one of only two living species of the family Giraffidae, the other being the okapi. The family was once much more extensive, with over 10 fossil genera described. Giraffids first arose 8 million years ago (mya) in south-central Europe during the Miocene epoch. The superfamily Giraffoidea, together with the family Antilocapridae (whose only extant species is the pronghorn), evolved from the extinct family Palaeomerycidae.[11] The earliest known giraffid was the deer-like Climacoceras.

While the progressive elongation of the neck and limbs can be found throughout the giraffid lineage, it became more pronounced in genera such as Samotherium and Bohlinia.[11] Bohlinia entered China and northern India in response to climate change. From here, the genus Giraffa evolved and, around 7 mya, entered Africa.[11] Further climate changes caused the extinction of the Asian giraffes, while the African ones survived and radiated into several new species. G. camelopardalis arose around 1 mya in eastern Africa during the Pleistocene.[11] Some biologists suggest that the modern giraffe descended from G. jumae[12] while others find G. gracilis a more likely candidate.[11] It is believed that the main driver for the evolution of the giraffes were the changes in biome from extensive forests to more open habitats, which began 8 mya.[11]

The giraffe was one of the many species first described by Carl Linnaeus in 1758. He gave it the binomial name Cervus camelopardalis in the 10th edition of his Systema Naturae.[13] Morten Thrane Brünnich classified the genus Giraffa in 1772.[14] In the early 19th century, Jean-Baptiste Lamarck believed that the giraffe's long neck was an "acquired characteristic", developed as generations of ancestral giraffes strived to reach the leaves of tall trees.[15] This theory was eventually rejected, and scientists now believe that the giraffe's neck arose through Darwinian natural selection—that ancestral giraffes with long necks thereby had a competitive advantage that better enabled them to reproduce and pass on their genes.[15]

Subspecies

Approximate geographic ranges, fur patterns and phylogenetic relationships between some giraffe subspecies based on mitochondrial DNA sequences. Colored dots on the map represent sampling localities. The phylogenetic tree is a maximum-likelihood phylogram based on samples from 266 giraffes. Asterisks along branches correspond to node values of more than 90 percent bootstrap support. Stars at branch tips identify paraphyletic haplotypes found in Masai and Reticulated giraffes.[16]

Up to nine subspecies of giraffe are recognized (with population estimates as of 2010):

  • G. c. camelopardalis,[17] the nominate subspecies, is known as the Nubian giraffe. Its coat pattern has large, four-sided patches, with no spots on the inner sides of the legs or below the hocks. It is found in eastern South Sudan and south-western Ethiopia. It is estimated that fewer than 250 remain in the wild, although this estimate is uncertain.[18] It is rare in captivity, although a group is kept at Al Ain Zoo in the United Arab Emirates.[19] In 2003, this group numbered 14.[20]
  • G. c. reticulata,[17] known as the Reticulated[17] or Somali giraffe, has a coat pattern of well-defined patches with sharp edges, separated by thin lines.[21] It is native to north-eastern Kenya, southern Ethiopia and Somalia. It is estimated that no more than 5,000 remain in the wild,[18] and based on ISIS records, more than 450 are kept in zoos.[22]
  • G. c. angolensis, the Angolan or Namibian giraffe has large spots with some notches around the edges, extending down the entire lower leg. It is found in northern Namibia, south-western Zambia, Botswana and western Zimbabwe. One genetic study on Smoky giraffes suggests that the northern Namib Desert and Etosha National Park populations form a distinct subspecies.[23] It is estimated that no more than 20,000 remain in the wild;[18] based on ISIS records approximately 20 are kept in zoos.[22]
  • G. c. antiquorum,[17] the Kordofan giraffe, has small, more irregular patches, which do not extend to the lower legs. Its distribution includes southern Chad, the Central African Republic, northern Cameroon and north-eastern DR Congo. Populations in Cameroon were formerly included in G. c. peralta, but this was incorrect.[24] No more than 3,000 are believed to remain in the wild.[18] Considerable confusion has existed over the status of this subspecies and G. c. peralta in zoos. In 2007 it was shown that all alleged G. c. peralta in European zoos were, in fact, G. c. antiquorum.[24] With this correction, based on ISIS records, approximately 65 are kept in zoos.[22]
  • G. c. tippelskirchi,[17] known as the Maasai giraffe[17] or Kilimanjaro giraffe, has an irregular pattern of jagged-edged patches.[21] It can be found in central and southern Kenya and in Tanzania. It is estimated that no more than 40,000 remain in the wild,[18] and based on ISIS records, approximately 100 are kept in zoos.[22]
The endangered West African giraffe
  • G. c. rothschildi,[17] is known variously as the Rothschild giraffe,[17] Baringo giraffe or Ugandan giraffe. Its coat bears a blotched or rectangular pattern, which does not extend to the lowe legs. Its range includes Uganda and west-central Kenya, especially near Lake Baringo. It may also be found in South Sudan.[25] The Rothschild giraffe had been considered a hybrid population,[26] but genetic evidence confirms that it is a valid subspecies.[16] Fewer than 700 are believed to remain in the wild,[18] and based on ISIS records, more than 450 are kept in zoos.[22]
  • G. c. giraffa, the South African giraffe, has rounded or blotched spots, some with star-like extensions, running down to the hooves. It is found in northern South Africa, southern Botswana, southern Zimbabwe and south-western Mozambique. It is estimated that no more than 12,000 remain in the wild,[18] and based on ISIS records, approximately 45 are kept in zoos.[22]
  • G. c. thornicrofti,[17] called the Thornicroft giraffe[17] or Rhodesian giraffe, has leaf-shaped spots extending to the lower leg. It is restricted to the Luangwa Valley in eastern Zambia. No more than 1,500 remain in the wild,[18] and based on ISIS records, none are kept in zoos.[22]
  • G. c. peralta,[17] commonly known as the West African giraffe[17] or Niger giraffe, has a light complexion, with rectangular spots. It is endemic to southern Niger. Fewer than 220 individuals remain in the wild.[18] Giraffes in Cameroon were formerly believed to belong to this subspecies, but are actually G. c. antiquorum.[24] This error resulted in some confusion over its status in zoos, but in 2007 it was established that all "G. c. peralta" kept in European zoos actually are G. c. antiquorum.[24]

Although giraffes from these populations interbreed freely in captivity, suggesting that they are subspecific populations, a 2007 study published in BMC Biology has suggested that there may be at least six species of giraffe that are reproductively isolated and do not interbreed, even though no natural obstacles, such as mountain ranges or impassable rivers, block their mutual access. The study deduced from genetic drift in nuclear and mitochondrial DNA that the two giraffe populations living closest to each other—the reticulated giraffe and the Maasai giraffe—separated genetically 0.13–1.62 mya.[16] The implications of these findings for the conservation of giraffes were summarised by David Brown, lead author of the study, who told BBC News: "Lumping all giraffes into one species obscures the reality that some kinds of giraffe are on the brink. Some of these populations number only a few hundred individuals and need immediate protection."[27]

Appearance and anatomy

Closeup of the head of a giraffe at the Melbourne Zoo
Giraffe skeleton on display by The Museum of Osteology, Oklahoma City, Oklahoma

A fully grown giraffe is typically 5.8 m (19 ft) tall, with males taller than females.[14] The average weight is 1,600 kg (3,500 lb) for an adult male and 830 kg (1,830 lb) for an adult female. The coat has dark blotches or patches (which can be orange, chestnut, brown or nearly black on color[15]) separated by light hair (usually white or cream in color[15]). Each individual giraffe has a unique coat pattern.[21] The coat pattern serves as camouflage, allowing it to blend in the savanna woodlands.[17] In particular, the patches may also serve as windows for thermoregulation, being sites for complex blood vessel systems and large sweat glands.[28] Giraffes have thick skin which allows them to run through thorn bush without much injury.[29]: 34  Their fur may serve as a chemical defence, as it is full of parasite repellents that give the animal a characteristic scent. There are at least eleven main aromatic chemicals in the fur, although indole and 3-methylindole are responsible for most of the smell. Because the males have a stronger odour than the females, it is suspected that it also has a sexual function.[30] Along the animal's neck is a brown mane made of short, erect hairs.[14] The tail has a tuft of long, dark hair at the end[21] and is used to swat flies away.[14]

Located at both sides of the head, the giraffe's large, bulging eyes give it good all-round vision from its great height.[29]: 25  Giraffes are capable of seeing in color[29]: 26  and their senses of hearing and olfaction are also sharp.[15] The animal can protect against sandstorms and the ants that inhabit the trees it feeds on, by closing its muscular nostrils.[29]: 27  The giraffe's prehensile tongue is about 50 cm (20 in) long.[29]: 27  It is purplish-black in color, perhaps to protect against sunburn, and is useful for grasping foliage as well as for grooming and cleaning the animal's nose.[29]: 27  The upper lip of the giraffe is also prehensile and useful when foraging. The lips, tongue and inside of the mouth are covered in papillae to protect against thorns.[14]

Skull and horns

Both sexes have prominent horns, or ossicones, formed from ossified cartilage, covered in skin and fused to the skull at the parietal bones.[21] Their appearance is a reliable method of identifying the sex of a giraffe: the horns of females display tufts of hair on top, whereas those of males are larger and tend to be bald on top.[21] There is also a median horn, which is larger in males, at the front of the skull.[14] Males develop calcium deposits that form bumps on their skulls as they age, sometimes giving the appearance of additional horns.[15] Being vascularized, the horns may have a role in thermoregulation.[28] A giraffe's skull is filled with sinuses.[14] However, as males age, their skulls become heavier and more club-like, helping them become more dominant in combat.[21] The upper jaw has a grooved palate and lacks front teeth.[29]: 26  The surface of the giraffe's molars are rougher than those of some other mammals.[29]: 27 

Legs, locomotion and posture

The front legs of a giraffe are about 10 percent longer than its hind legs. The radius and ulna of the front legs are articulated by the carpus which, while structurally equivalent to the human wrist, functions as a knee.[31] The rear of each hoof is low and the fetlock is close to the ground, allowing the foot to support the animal's weight.[14] Giraffes lack dewclaws. The giraffe's pelvis, though relatively short, has a ilium that is outspread at the upper ends.[14]

A giraffe has only two gaits: walking and galloping. Walking is done by moving the legs on one side of the body at the same time, then doing the same on the other side.[21] When galloping, the hind legs move around the front legs before the latter move forward,[15] and the tail will curl up.[21] The animal relies on the forward and backward motions of its head and neck to maintain balance while galloping.[10]: 327–29  The giraffe can reach a sprint speed of up to 60 km/h (37 mph).[32]

A giraffe rests by lying down with its body on top of its folded legs.[10]: 329  To lie down, the animal kneels on its front legs and then lowers the rest of its body. To get back up, it first gets on its knees, splays its hind legs and raises its hindquarters. It then straightens its front legs. With each step, the animal swings its head.[29]: 31  The giraffe has one of the shortest sleep requirements of any mammal, averaging around 4.6 hours of fragmented sleep per day, mostly at night.[33] It sleeps lying down, curled up and with its head resting on the rump or hind leg.[29]: 33  If it wants to bend down to drink, the giraffe either spreads its front legs or bends its knees.[21] Giraffes would probably not be capable swimmers as their long legs would be highly resistant to rotation changes in the water.[34] While they may be able to float, "they would be clumsy and unstable in water".[35] When swimming, the thorax will be weighed down by the front legs, making it difficult for the animal to move its neck and legs in harmonization or keep the former above the surface.[34][35]

Neck

An adult male giraffe feeding high up on an acacia

The giraffe has an extremely elongated neck, which can be over 2 m (6 ft 7 in) in length,[36] accounting for nearly half of the animal's vertical height. The long neck results from a disproportionate lengthening of the cervical vertebrae, not from the addition of more vertebrae. The cervical vertebrae comprise 45–50 percent of the giraffe's vertebral column, compared with the 30 percent typical of similar large ungulates, including the giraffe’s closest living relative, the okapi. This elongation, which occurs in large part after birth,[37] makes the vertebrae 150 percent longer than those of similar-sized animals. The giraffe's head and neck are held up by large muscles and a nuchal ligament, which are anchored by long dorsal spines on the anterior thoracic vertebrae, giving the animal a hump.[14]

The giraffe has a modified atlas-axis joint (C1 and C2), which functions like a ball and socket joint.[29]: 29  This allows the animal to tilt its head vertically and reach more branches with the tongue. The point of articulation between the cervical and thoracic vertebrae of giraffes is shifted to lie between the first and second thoracic vertebrae (T1 and T2), rather than between the seventh cervical vertebra (C7) and T1, as in most other ruminants.[36][37] This allows C7 to contribute directly to increased neck length and has given rise to the suggestion that T1 is actually C8, and giraffes have added an extra cervical vertebra.[38] However, this proposition is not generally accepted, as T1 has other morphological features, such as an articulating rib, deemed diagnostic of thoracic vertebrae, and because exceptions to the mammalian limit of seven cervical vertebrae are generally characterized by increased neurological anomalies and maladies, symptoms that have not been observed in giraffes.[36]

There are two main hypotheses regarding the evolutionary origin and maintenance of elongation in giraffe necks.[39] The "competing browsers hypothesis" was originally suggested by Charles Darwin and only challenged recently. It suggests that competitive pressure from smaller browsers, such as kudu, steenbok and impala, encouraged the elongation of the neck, as it enabled giraffes to reach food that competitors could not. This advantage is real, as giraffes can and do feed up to 5 m (16 ft) high, while even quite large competitors, such as kudu, can only feed up to about 2 m (6 ft 7 in) high.[40] There is also research suggesting that browsing competition below 2 m is intense, and giraffes feed more efficiently (gaining more leaf biomass per bite) higher in the canopy.[41][42] However, scientists disagree about just how much time giraffes spend feeding at levels beyond the reach of other browsers.[12][39][40][43]

The other main theory, the sexual selection hypothesis, proposes that the long necks evolved as a secondary sexual characteristic, giving males an advantage in "necking" contests (see below) to establish dominance and obtain access to sexually receptive females.[12] In support of this theory, necks are longer and heavier for males than females of the same age,[12][39] and the former do not employ other forms of combat.[12] However, one criticism of this theory is that it fails to adequately explain why female giraffes also have long necks.[44]

Internal systems

Giraffe bending down to drink

In mammals, the left recurrent laryngeal nerve is longer than the right; in the giraffe it is over 30 cm (12 in) longer. This nerve is longer in the giraffe than in any other living animal;[45] the left nerve is over 2 m (6 ft 7 in) long.[46] Each nerve cell in this path begins in the brainstem and passes down the neck along the vagus nerve, then branches off into the recurrent laryngeal nerve which passes back up the neck to the larynx. Thus, these nerve cells have a length of nearly 5 m in the largest giraffes.[45] The structure of a giraffe's brain resembles that of domestic cattle.[29]: 31  The shape of the skeleton gives the giraffe a small lung volume relative to its mass.[47] Its long neck gives it a high amount of dead space, in spite of its narrow windpipe. These factors give it a low respiratory rate. Nevertheless, the animal can still supply enough oxygen to its tissues.[47]

The circulatory system of the giraffe has several adaptations for its great height. Its heart, which can weigh more than 25 lb (11 kg) and measures about 2 ft (61 cm) long, must generate approximately double the blood pressure required for a human to maintain blood flow to the brain.[15] In the upper neck, a complex pressure-regulation system called the rete mirabile prevents excess blood flow to the brain when the giraffe lowers its head to drink.[17] The jugular veins also contain several (most commonly seven) valves to prevent blood flowing back into the head from the inferior vena cava and right atrium while the head is lowered.[48] Conversely, the blood vessels in the lower legs are under great pressure (because of the weight of fluid pressing down on them). To solve this problem, the giraffe's lower legs have a thick, tight layer of skin, which prevents too much blood from pouring into them.[17] The digestive system of the giraffe has a smaller ratio of small to large intestine than that of domestic cattle.[49]

Behavior and ecology

Habitat and feeding

Giraffe extending its tongue to feed. Its tongue, lips and palate are tough enough to deal with sharp thorns in trees.

Giraffes usually inhabit savannas, grasslands and open woodlands. They prefer Acacia, Commiphora, Combretum and open Terminalia, moreso than denser enviroments like Brachystegia woodlands.[10]: 322  The Angolan giraffe is known to inhabit desert environments.[50] Giraffes browse on the twigs of trees, preferring trees of genera Acacia, Commiphora and Terminalia.[26] They also feed on shrubs, grass and fruit.[10]: 324  A giraffe eats around 34 kg (75 lb) of foliage daily.[21]

During the wet season, food is abundant and giraffes disperse widely, but during the dry season they need to congregate around evergreen trees and bushes.[26] Mothers tend to feed in open areas, presumably to make it easier to detect predators, although this may reduce their feeding efficiency.[43] As a ruminant, the giraffe first chews its food, then swallows it for processing and then visibly passes the half-digested cud up the neck and back into the mouth to chew again. This process is usually repeated several times for each mouthful. The giraffe requires less food than many other herbivores, because the foliage it eats has more concentrated nutrients and it has a more efficient digestive system.[26] It is common for a giraffe to salivate while feeding.[29]: 27  When it has access to water, a giraffe drinks at intervals no longer than three days.[21]

Giraffes have a great effect on the trees that they feed on, delaying the growth of young trees for some years and giving "waistlines" to trees that are too tall.[21] Feeding is at its highest during the first and last hours of daytime.[21] A giraffe mostly stands and ruminates inbetween these hours. Rumination is the dominant activity during the night, when it is mostly done lying down.[21]

Social structure and breeding habits

Male giraffe mounting a female. Only dominant males are generally able to mate.

While giraffes are usually found in groups, the composition of these groups is more fluid than in other social ungulates.[51] They have few strong social bonds, and aggregations usually disband every few hours, although calving groups can last weeks or months.[52] For research purposes, a "group" has been defined as "a collection of individuals that are less than a kilometre apart and moving in the same general direction."[53] Giraffe groups usually consist of just a few members, although 40 or more occur on occasion.[54] Adult males tend to be solitary.[52] Female giraffes associate in groups of roughly a dozen, occasionally including a few younger males. Calves and subadults are rarely alone.[53] Playfighting is known to occur among subadult males.[52] Giraffes are not territorial,[14] but they have home ranges.[21] Male giraffes occasionally wander far from areas that they normally frequent.[10]: 329 

Reproduction is broadly polygamous: a few older males mate with the the fertile females. Male giraffes assess female fertility by tasting the female's urine in order to detect estrus, in a multi-step process known as the Flehmen response.[52][53] Once an estrous female is detected, the male will attempt to court her.[53] Males prefer younger females, possibly because the latter are more fertile, while females prefer older, more dominant males.[52][53] During courtship, dominant males will displace subordinate ones from the presence of the females by staring and walking towards them. The female prolongs the courtship process for as long as possible, so only the most dominant male remains to mate with. During copulation, the male stands on its hind legs with its head held up and its front legs resting on the female's sides.[21] Homosexual interactions have also been observed in giraffes. In one study, up to 94 percent of observed mounting incidents took place between males. The proportion of same-sex activities varied from 30–75 percent. Only one percent of same-sex mounting incidents occurred between females.[55]

Although generally quiet and non-vocal, giraffes have been heard to communicate with various sounds. During courtship, males emit loud coughs.[21] Females call their young by bellowing. Calves will emit snorts, bleats and moo/mewing sounds. Other sounds made include snores, hisses, moans and flute-like sounds.[21] Giraffes are also known to communicate over long distances using infrasound.[56]

Birthing and parental care

Mother giraffe and calves feeding. It is mostly the females that raise young, and they may gather in nursery herds.

Giraffe gestation lasts 400–460 days, after which a single calf is normally born, although twins occur on rare occasions.[57] The mother gives birth standing up, and both amniotic sac and umbilical cord usually break when the newborn falls to the ground. The mother then grooms the newborn and helps it stand up.[29]: 40  A newborn giraffe is about 1.8 m (6 ft) tall. Within a few hours of birth, the calf can run around and is almost indistinguishable from a one-week-old; however, for the first two weeks, it spends most of its time lying down, guarded by the mother.[52][58] Their coat pattern provides camouflage when they are hiding. The horns, which have lain flat since it was in the womb, become erect within a few days.[21]

Mothers with calves will gather in nursery herds consisting of two or more infants and/or juveniles and their mothers moving or browsing together.[58] Mothers in such a group may sometimes leave their calves with one female while they travel to other areas. This is known as a "calving pool".[58] Social cohesion in nursery groups are maintained by the bonds formed between calves.[10]: 330  Adult males play almost no role in raising the young, who are vulnerable to predators.[10]: 337  A mother giraffe will stand over its young and kick at an approaching predator.[21] Giraffes only defend their own young; they form calving herds for selfish reasons.[58] The bond a mother shares with its calf lasts until the former's next calving.[58] Calves are weaned after 13 months, however associations between mothers and offspring continue for another 2–5 months.[52]

Male giraffes will engage in necking to establish dominance.

Necking

Male giraffes use their necks as weapons in combat, a behavior known as "necking".[59] Necking is used to establish dominance and can occur at low or high intensity. In low intensity necking, the combatants rub and lean against each other. The male that can hold itself more erect wins the bout.[21] In high intensity necking, the combatants will spread their front legs and swing their necks at each other, attempting to land blows with their horns.[21] The contestants will try to dodge each other's blows and then get ready to counter. The power of a blow depends on the weight of the skull and the arc of the swing.[21] A necking duel can last over half an hour, depending on how well matched the combatants are. The winner will mount his opponent in a show of dominance.[10]: 331–32  Males that are successful in necking have greater reproductive success.[12]

Mortality and health

Healthy adult giraffes are almost invulnerable to predation;[21] a giraffe can defend itself with powerful kicks, which are capable of killing a predator. Calves, on the other hand, are preyed on by lions, leopards, spotted hyenas and wild dogs.[15] A quarter to a half of giraffe calves reach adulthood. Maximum lifespan is around 25 years in the wild.[17] Adult giraffes can fall prey to lions if the cats can make them fall over.[21] In Kruger National Park, lions commonly prey on adult giraffes.[60] Nile crocodiles can also be a threat to giraffes when they bend down to drink.[29]: 31 

Some parasites feed on giraffes. They are often hosts for ticks, especially in the area around the genitals, which has thinner skin than other areas.[14] Tick species that commonly feed on giraffes are those of genera Hyalomma, Amblyomma and Rhipicephalus.[14] Giraffes may rely on red-billed and yellow-billed oxpeckers to clean them of ticks and alert them to danger.[14] Giraffes host numerous species of internal parasite[14] and are susceptible to various diseases. They were victims of the (now eradicated) viral illness rinderpest.[14]

Relationship with humans

Cultural significance

Bushmen rock art in Namibia depicting a giraffe

Humans have interacted with giraffes for millennia. The Bushmen of southern Africa have medicine dances named after some animals; the giraffe dance is performed to treat head ailments.[61] How the giraffe got its height has been the subject of various African folktales,[12] including one from eastern Africa which explains that the giraffe grew tall from eating too much magic herbs.[62] Giraffes were depicted in art throughout the African continent, including that of the Kiffian, Egyptians and Meroë Nubians.[29]: 45–47  The Kiffian were responsible for a life-size rock engraving of two giraffes, which has been called the "world's largest rock art petroglyph".[29]: 45 [63] The Egyptians gave the giraffe its own hieroglyph; its name being 'sr' in Old Egyptian and 'mmy' in later periods.[29]: 49  They also kept giraffes as pets and shipped them around the Mediterranean.[29]: 48–49 

The giraffe was also known to the Greeks and Romans, who believed that it was an unnatural hybrid of a camel and a leopard, and referred to as camelopardalis.[29]: 50  The giraffe was among the many animals collected and displayed by the Romans. The first giraffe in Rome was brought in by Julius Caesar in 46 BC and exhibited to the public.[29]: 52  With the fall of the Roman Empire, housing of giraffes in Europe declined.[29]: 54  During the Middle Ages, giraffes were only known to Europeans through contact with Arabs.[15] Arab prophets and poets revered the giraffe for its peculiar appearance.[15]

Painting of a giraffe imported to China during the Ming Dynasty

In 1414, a giraffe was shipped from Malindi to Bengal. It was then taken to China by explorer Zheng He and placed in a Ming Dynasty zoo. The animal was a source of fascination for the Chinese people, who associated it with the mythical Qilin.[29]: 56  The Medici giraffe was a giraffe presented to Lorenzo de' Medici in 1486. It caused a great stir on its arrival in Florence,[64] being reputedly the first living giraffe to be seen in Italy since antiquity. Another famous giraffe, called Zarafa, was brought from Egypt to Paris in the early 19th century. A sensation, Zarafa was the subject of numerous memorabilia or "giraffanalia".[29]: 81 

Giraffes continue to have a presence in modern culture. Salvador Dalí depicted them with conflagrated manes in some of his surrealist paintings. Dali considered the giraffe to be a symbol of masculinity, and a flaming giraffe was meant to be a "masculine cosmic apocalyptic monster".[29]: 123  Giraffes have also appeared in animated films, as minor characters in The Lion King and Dumbo, and in more prominent roles in The Wild and in the Madagascar films. Sophie the Giraffe has been a popular teether since 1961.[29]: 127  Another famous fictional giraffe is the Toys "R" Us mascot Geoffrey the Giraffe.[29]: 127 

The giraffe has also been used for some scientific experiments and discoveries. Its skin has been studied by NASA scientists developing suits for astronauts.[65] The properties of the skin have been useful for these studies, since people this profession face the risk of passing out if blood rushes to their legs. Computer scientists have modeled the coat patterns of several subspecies using reaction–diffusion mechanisms.[66] The constellation of Camelopardalis depicts a giraffe.[29]: 119–20 

Exploitation and conservation status

Giraffe killed by tribesmen in the early 20th century

Giraffes were probably common targets for hunters throughout Africa.[10]: 337  Different parts of their bodies were used for different purposes.[14] Their meat used for food. The tail hairs served as flyswatters, braclets, necklaces and thread.[10]: 337 [14] Shields, sandals and drums were made using the skin and the strings of musical instruments were from the tendons.[14] The smoke of burning giraffe skins was used by the medicine men of Buganda to treat nose bleeds.[10]: 337  European explorers also hunted them.[14][29]: 129  Habitat destruction has hurt the giraffe, too: in the Sahel, the need for firewood and grazing room for livestock has lead to deforestation.[17] Normally, giraffes can coexist with livestock, since they do not directly compete with them.[17]

Overall, the giraffe is assessed as Least Concern from a conservation perspective by the IUCN, as it is still numerous.[2] However, giraffes have been extirpated from Burkina Faso, Eritrea, Guinea, Malawi, Mauritania and Senegal.[2] They may also have disappeared from Angola, Mali, and Nigeria, but have been introduced to Rwanda and Swaziland.[2] Two subspecies, the West African giraffe and the Rothschild giraffe, have been classified as Endangered,[25][67] as wild populations of each of them number in the hundreds.[18] In 1997, Jonathan Kingdon suggested that the Nubian giraffe was the most threatened of all giraffes;[26] as of 2010, it may number fewer than 250, although this estimate is uncertain.[18] Private game reserves have contributed to the preservation of giraffe populations in southern Africa.[17] The giraffe is a protected species in most of its range. In 1999, it was estimated that over 140,000 giraffes existed in the wild.[18] However, estimates in 2010 indicate that fewer than 80,000 remain.[18]

References

  1. ^ Grubb, P. (2005). "Giraffa camelopardalis". In Wilson, D. E.; Reeder, D-A. M (ed.). [http://www.google.com/books?id=JgAMbNSt8ikC&pg=PA672#v=onepage&q&f=false Mammal Species of the World: A Taxonomic and Geographic Reference] (3rd ed.). Johns Hopkins University Press. p. 672. ISBN 9780801882210. OCLC 62265494. {{cite book}}: External link in |title= (help)CS1 maint: multiple names: editors list (link)
  2. ^ a b c d Template:IUCN2008
  3. ^ a b c "Giraffe". Online Etymology Dictionary. Retrieved 2011-11-01.
  4. ^ Peust, C. (2009). "Some Cushitic Etymologies". Semito-Hamitic Festschrift for A.B. Dolgopolsky and H. Jungraithmayr. Reimer. pp. 257–60. ISBN 3496028106. {{cite book}}: Unknown parameter |editors= ignored (|editor= suggested) (help)
  5. ^ "camelopardalis". A Latin Dictionary, Perseus Digital Library. Retrieved 2011-11-23.
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  7. ^ "κάμηλος". A Greek-English Lexicon, Perseus Digital Library. Retrieved 2011-11-23.
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  67. ^ Template:IUCN2008

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