Giraffe

Giraffe[1]
A Maasai giraffe in Mikumi National Park, Tanzania
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Family: Giraffidae
Genus: Giraffa
Species: G. camelopardalis
Binomial name
Giraffa camelopardalis
(Linnaeus, 1758)
Range map of the giraffe divided by subspecies.

The giraffe (Giraffa camelopardalis) is an African even-toed ungulate mammal, the tallest extant terrestrial animal and the largest ruminant. Its specific name refers to its camel-like face and irregular 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 5–6 m (16–20 ft) tall and has an average weight of 1,200 kg (2,600 lb) for males and 830 kg (1,800 lb) for females. It is classified under the family Giraffidae, along with its closest extant relative, the okapi. There are nine subspecies of giraffe, which differ in size, coloration, pattern and range.

The giraffe's range extends from Chad in the north to South Africa in the south and from Niger in the west to Somalia in the east, but it is very scattered. Giraffes usually inhabit savannas, grasslands and open woodlands. They prefer areas with plenty of acacia trees, which are important food sources. Owing to their extreme height, giraffes can browse for vegetation that most other herbivores cannot reach. While adults are nearly invulnerable to predation, lions, leopards, spotted hyenas and wild dogs prey on calves. Although they commonly gather together, giraffe aggregations usually disband every few hours. Male giraffes use their necks as weapons in combat, a behavior known as "necking". Dominant males each mate with multiple females. Females bear the sole responsibility for raising their 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. The giraffe is classified by the IUCN as Least Concern. However, it has been extirpated from many parts of its former range, and some subspecies are classified as endangered. Nevertheless, giraffes are still found in numerous reserves.

Contents

Etymology and naming

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] The Italian form giraffa arose in the 1590s from Arabic.[3] It appears in English from the 16th century through the French girafe.[3] The species name camelopardalis is a Latin word,[4] a romanization of the Greek καμηλοπάρδαλις,[5] from κάμηλος (kamēlos), "camel",[6] + πάρδαλις (pardalis), "leopard".[7] Kameelperd is also the name for the species in Afrikaans.

Taxonomy and evolution

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. The ancestors of modern giraffids probably evolved 8 mya in southern central Europe during the Miocene epoch. The Giraffidae, together with the family Antilocapridae (whose only extant species is the pronghorn), evolved from the extinct family Palaeomerycidae.[9] The earliest known giraffid was the deer-like Climacoceras. While the progressive elongation of the neck and limbs can be traced to the early giraffids, it became more pronounced in later genera such as Palaeotragus (from which the okapi evolved), Samotherium and Bohlinia.[9] Bohlinia entered China and northern India in response to climate change. Genus Giraffa evolved from it, with a number of long-necked species. Around 7 mya, Giraffa entered Africa through Ethiopia.[9] Further climate changes caused the extinction of the Asian giraffes, while the African ones survived and radiated into several new species.[9] The modern G. camelopardalis arose around 1 mya in East Africa during the Pleistocene.[9] Some biologists suggest that the modern giraffe descended from G. jumae[10] while others find G. gracilis a more likely candidate.[9]

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.[11] Morten Thrane Brünnich classified the genus Giraffa in 1772.[12] 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.[13] This theory was eventually rejected, and most scientists now believe that the giraffe's neck arose though Darwinian natural selection—that ancestral giraffes with long necks thereby had a competitive advantage that better enabled them to repoduce and pass on their genes.[13]

Subspecies

Different authorities have recognized different numbers of subspecies, distinguished by size, coloration, coat pattern and range.[1][2][12][15] Up to nine subspecies are recognized (with population estimates as of 2010):

G. c. angolensis  
G. c. antiquorum  
G. c. camelopardalis  
G. c. giraffa  
G. c. peralta  
G. c. reticulata  
G. c. rothschildi  
G. c. thornicrofti  
G. c. tippelskirchi  

Some scientists have proposed four other subspecies—Cape giraffe (G. c. capensis), Lado giraffe (G. c. cottoni), Congo giraffe (G. c. congoensis) and Transvaal giraffe (G. c. wardi)—but none of them are widely accepted.[1]

Although giraffes from these populations interbreed freely in captivity, suggesting that they are subspecific populations, genetic testing published in 2007 has been interpreted to show 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 (G. camelopardalis reticulata) of north Kenya and the Maasai giraffe (G. c. tippelskirchi) of south Kenya and Tanzania—separated genetically between 0.13 and 1.62 million years ago.[14]

The implications for conservation of as many as eleven such cryptic species and subspecies were summarised by David Brown for 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."[25]

Physical appearance and anatomy

A fully grown giraffe is typically 5–6 m (16–20 ft) tall, with males taller than females.[12] The average weight is 1,200 kg (2,600 lb) for an adult male and 830 kg (1,800 lb) for an adult female.[12][26] The coat is made up of brown blotches or patches separated by lighter hair. Each giraffe has a unique coat pattern.[27] The coat pattern serves as camouflage, mimicking the dappled combination of light and shade in savanna woodlands.[16] In particular, the patches may also serve as thermal windows, being the 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, stiff hairs.[12] The tail has a black terminal tuft[27] and is used to swat flies away.[12]

The giraffe has fairly large eyes, which are mounted at both sides of the head and bulge outward, providing the animal good all-round vision from its great height.[29]:25 Giraffes are capable of seeing in color[29]:25 and have well-developed senses of hearing and olfaction.[13] The nostrils have muscular openings, which allow the animal to open and close them. This may serve to protect against sandstorms and the ants that inhabit the trees it feeds on.[29]:27 The giraffe's tongue is about 50 cm (20 in) long and prehensile.[29]:27 It is purplish-black in color, perhaps to protect against sunburn,[29]:27 and is used to grip branches and strip leaves as well as for grooming and cleaning the animal's nose.[29]:27 The upper lip of the giraffe is also prehensile and can grasp foliage. The lips, tongue and inside of the mouth are covered in papillae to protect against thorns.[12]

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.[27] 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.[27] There is also a median horn, which is more developed in males, at the front of the skull.[12] Males sometimes develop calcium deposits that form bumps on their skulls as they age, sometimes giving the appearance of additional horns.[13] The horns are well vascularized and may also have a thermoregulatory function.[28] A giraffe's skull is fulled with air spaces.[12] However, as males age, their skulls become heavier and more club-like, helping them become more dominant in combat.[27] The upper jaw has a grooved palate which lacks front teeth.[29]:26 While most other mammals have teeth covered in smooth enamel, the giraffe's molars are low and crowned with a ridged, wrinkled surface.[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 nearly touches the ground, increasing the foot's ability to support the animal's weight.[12] Giraffes lack dewclaws. The pelvis is shorter in the giraffe than in most other ruminants, and the ilium has more expanded upper ends.[12]

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.[27] When galloping, the giraffe's front and hind legs work in pairs. The animal brings its hind legs ahead of and outside its front legs. The front legs then move forward.[13] While galloping, the tail will curl up.[27] The head and neck also move back and forth to maintain balance and counter the momentum.[8]:327-29 The giraffe can reach a sprint speed of up to 60 km/h (37 mph)[32] but cannot sustain a lengthy chase.

A giraffe prefers to rest lying with its legs folded underneath its body.[8]:329 To lie down, the animal kneels on its front legs and then lowers the rest of its body. To get back up, it gets on its knees and swings its head up with a jerk as the front legs straighten. It then splays its hind legs and raises its hindquarters.[8]:329 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 can sleep lying down with its neck folded and its head resting on the rump or hind leg.[8]:329 If it wants to bend down to drink, the giraffe either spreads its front legs or bends its knees.[27]

Giraffes are assumed to be unable to swim. It has been estimated that the giraffe's proportionally larger limbs have high rotational inertia that would make rapid swimming motions strenuous.[34] A swimming giraffe would be forced into a posture where the neck is sub-horizontal, and since the thorax would be pulled downwards by the large fore limbs, it would not be able to move the neck and limbs synchronously in the water, as it does when moving on land. This might further hamper the animal's ability to move its limbs effectively under water.[34] A computer simulation conducted by Scientific American suggested that, while giraffes could float, "they would be clumsy and unstable in water".[35] The simulation suggests that the high density of the giraffe's limb bones would make it slow and cause it to experience high drag.[35] Furthermore, the weight of the forelimbs and shoulder would pull the front of the giraffe down, straining its neck.[35]

Neck

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 supported by the long dorsal spines of the anterior thoracic vertebrae, forming a shoulder hump.[12] This is similar to the design of a crane.[16]

The giraffe has a modified atlas-axis joint (C1 and C2), which functions like a ball and socket joint.[29]:29 This allows the head to tilt vertically and, with its long tongue, the animal can reach branches that are an extra 1 m (3 ft 3 in) above it's head. 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 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.[39][40][43] Although giraffes can feed as low as 0.5 m (1 ft 8 in) and as high as 6 m (20 ft) above the ground, it appears that they most often feed at 2–4 m (6 ft 7 in–13 ft 1 in).[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.[10] In support of this theory, males have longer and heavier necks than females of the same age,[10][39] and necking is the only form of combat recorded in male giraffes. Males in this species do not employ biting, kicking, butting or head wrestling, as do other mammals, including the okapi.[10] However, one criticism of this theory is that it fails to adequately explain why female giraffes also have long necks.[44]

Internal systems

In mammals, the left recurrent laryngeal nerve is longer than the right; in the giraffe it is over 30 cm longer. The recurrent laryngeal nerve is longer in the giraffe than in any other extant animal;[46] the left nerve is over 2 m (6 ft 7 in) long.[47] 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 approaching 5 m (16 ft) in the largest giraffes.[46] The brain of a giraffe is similar in structure to that of domestic cattle.[29]:31 The shape of the skeleton gives the giraffe a smaller lung volume than expected for an animal of its mass.[48] Its long neck gives it a high amount of dead space, in spite of its narrow windpipe. These factors further prolong the time it takes to inhale and exhale a single breath. Nevertheless, this does not appear to compromise the animal's ability to supply oxygen to tissues.[48] An increased tidal volume also tends to compensate for the high volume of dead space.

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.[13] 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.[16] 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.[49] Conversely, the blood vessels in the lower legs are under great pressure (because of the weight of fluid pressing down on them). In other animals such pressure would force the blood out through the capillary walls; giraffes, however, have a very tight sheath of thick skin over their lower limbs, which maintains high extravascular pressure.[16] Compared with domestic cattle, giraffes have a relatively short small intestine and a relatively long large intestine, giving it a small ratio of small to large intestine.[50]

Behavior and ecology

Habitat and feeding

Giraffes usually inhabit savannas, grasslands and open woodlands. They are most common in Acacia, Commiphora, Combretum and open Terminalia woodlands and much less common in denser Brachystegia woodland.[8]:322 Giraffes browse on the twigs of trees, preferring trees of genera Acacia, Commiphora and Terminalia.[15][51] They also feed on shrubs, grass and fruit.[8]:323–24 A giraffe can eat 65 lb (29 kg) of leaves and twigs daily, but can survive on just 15 lb (6.8 kg).[51]

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.[15] As a ruminant, it 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.[15] When feeding, it is common for a giraffe to produce excess saliva.[29]:27 The giraffe can survive without water for extended periods.[51] When water is available, it may drink at intervals of three days or less. Giraffes can also get water from green leaves, especially when covered in dew.[27]

Giraffes have a great effect on the trees that they browse on, keeping young trees short for a year longer than usual and forming "waistlines" around trees whose tops are unreachable.[8]:325 Browsing by giraffes gives trees a globular or hourglass shape and keeps bushes down to less than 1 m high.[8]:325 Feeding periods peak during the first and last hours of daylight.[27] In between those hours, a giraffe may pass the time standing and ruminating. Rumination is the dominant activity during the night, when it is mostly done lying down.[27]

Social structure and breeding habits

While giraffes are usually found in groups, the composition of these groups is more fluid than in other social ungulates.[52] They have few strong social bonds, and aggregations usually disband every few hours, although calving groups can last weeks or months.[53] 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."[54] Giraffe groups usually consist of just a few members, although 40 or more occur on occasion.[55] Adult males tend to be solitary.[53] Female giraffes associate in groups of roughly a dozen, occasionally including a few younger males. Calves and subadults are rarely alone.[54] Subadult males, in particular, are gregarious and may engage in playfights.[53] Giraffe groups with young tend to feed in more open areas, presumably to make it easier to detect predators, although it may reduce their feeding efficiency.[43] Giraffes are not territoral, but they have home ranges.[27] Male giraffes occasionally wander far from areas that they normally frequent.[8]:329

Reproduction is broadly polygamous: a few older males impregnate all 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.[53][54] Once an estrous female is detected, the male will attempt to court her.[54] Males prefer younger females, possibly because the latter are more fertile,[53][54] while females prefer older, more dominant males.[53][54] 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 slides its forelegs loosely on to the female's flanks and stands upright.[27] 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 between 30 and 75 percent. Only one percent of same-sex mounting incidents occurred between females.[56]

Although generally quiet and non-vocal, giraffes have been heard to communicate with various sounds. Courting males emit loud coughs.[27] Females call their young by whistling or bellowing. Calves bleat, moo or make mewing sounds. Giraffes also grunt, snort, hiss, make strange flute-like sounds,[27] and communicate over long distances using infrasound.[57]

Birthing and parental care

Giraffe gestation lasts between 400 and 460 days, after which a single calf is normally born, although twins occasionally occur.[58] 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 licks and cleans the newborn and encourages it to walk.[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.[53][59] 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.[27]

Mothers with calves will gather in nursery herds consisting of two or more infants and/or juveniles and their mothers moving or browsing together.[59] Mothers in such a group may sometimes leave their calves with one female while they travel to other areas.[59] This is known as a "calving pool".[59] Calves appear to form strong social bonds, facilitating social cohesion in nursery groups.[8]:330 Adult males play almost no role in raising the young. The young are vulnerable to predators.[8]:337 A mother giraffe will stand over her young and kick at any predator that approaches.[27] Giraffes only defend their own young; they form calving herds for selfish reasons.[59] A mother has a strong maternal bond with her calf, lasting until her next calving.[59] Calves suckle for 13 months and continue to associate with their mothers for another 2–5 months.[53]

Necking

Male giraffes use their necks as weapons in combat, a behavior known as "necking".[60] Necking is used to establish dominance and can occur at low or high intensity. In low intesity necking, the combatants gently rub their heads and necks together and lean heavily against each other, while flapping their ears and rubbing shoulders, perhaps to assess their comparative weights. The winner of such a bout is the male that can hold itself more erect.[27]

In high intensity necking, the combatants aim blows at each other's rump, flanks or neck. To prepare to strike, a giraffe will straddle with its front legs, draw its neck sideways and swing upward and downward over the shoulder, attempting to hit its opponent with its horns.[27] The contestants try to avoid being hit by moving their necks at the last moment and then get ready to counter. The power of a blow depends on the weight of the skull and the intensity of the swing.[27] An outmatched opponent is almost immediately dislodged, but combatants that are more evenly matched can keep up for over half an hour.[8]:331 At the end of such a bout, the winner will mount his opponent in a show of dominance.[8]:331–32 It appears that males that are successful in necking have greater access to estrous females.[10]

Mortality

Because of their size, adult giraffes are almost invulnerable to predation.[27] Calves, on the other hand, are preyed on by lions, leopards, spotted hyenas and wild dogs. A quarter to a half of giraffe calves reach adulthood. Maximum lifespan is around 25 years in the wild[16] and 28 years in captivity.[61]

Lions are capable of killing adult giraffes if they can make them fall over and then secure a bite on the throat or nose.[27] In Kruger National Park, giraffes of any age are an important food source for lions.[62] Nile crocodiles may also take giraffes when they bend down to drink.[29]:31 A giraffe can defend itself with powerful kicks which can kill a predator when well-placed.[13]

Some parasites also feed on giraffes. Ticks are known to infest them, especially in the area around the genitals, which has thinner skin than other areas.[12] Tick species that commonly feed on giraffes are those of genera Hyalomma, Amblyomma and Rhipicephalus.[12] Giraffes have mutualistic relationships with red-billed and yellow-billed oxpeckers, which clean them of ticks and alert them to danger.[12] Numerous species of internal parasite feed on giraffes,[12] and they are susceptible to various diseases. They were commonly affected by the (now eradicated) viral illness Rinderpest.[12]

Relationship with humans

Cultural significance

In Africa, the giraffe has been revered as a religious symbol, kept as a pet and traded as a diplomatic offering of goodwill.[29]:45 The Bushmen have medicine dances named after some animals; the giraffe dance is performed to cure head ailments.[63] Giraffes were commonly depicted in rock and cave art throughout the continent. Some of the earliest of these pictures were made by the palaeolithic Kiffian people, who lived around 8000 BC in modern-day Niger.[29]:45 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[64] The Ancient Egyptians commonly depicted giraffes in tomb paintings and may have kept them as pets.[29]:47–48 The Egyptians shipped giraffes from East Africa and exported them from Alexandria to ports around the Mediterranean.[29]:49 Giraffes were also known to the Ancient Greeks and the Ancient Romans, who referred to them as camelopardalis, a name thought to have derived from the belief that the giraffe was an unnatural cross between a camel and a leopard.[29]:50 The giraffe was among the many animals collected and displayed by the Romans as exotic spoils of conquered lands.[29]:52 The first giraffe in Rome was imported by Julius Caesar and exhibited to the public.[29]:52

With the fall of the Roman Empire, the people of Europe were no longer able to keep and display giraffes.[29]:54 During the Middle Ages, giraffes were mostly forgotten by Europeans, except in legends from Arab travelers.[13] Arab prophets and poets considered the giraffe the "queen of beasts" for what they saw as its delicate features and fragile form.[13] Eastern sultans prized them as special pets.[13] In 1414, a giraffe was taken from Malindi (in what is now Kenya) to Bengal. It was then taken to China by explorer Zheng He and placed in a Ming Dynasty zoo. Its arrival caused a sensation, as it was thought to be 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,[65] 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 in some of his surrealist paintings, most often in various states of conflagration. 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 is a popular teether that has been a favorite toy for babies 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 scientists developing suits for astronauts and fighter pilots.[66] The properties of the skin have been useful for these studies, since people in these professions 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.[67] The constellation of Camelopardalis depicts a giraffe.[29]:120

Conservation status

Giraffes were probably a favorite target for the hunters of the Sahara, the Kalahari and central and eastern Africa.[8]:337 They were hunted for their tails, hides and meat.[12][51] The tails were used as good luck charms, for thread and as flyswatters;[51] the skin was used for shields, sandals and drums;[12] the tendons were used for stringed instruments and thread; the hairs were used to make necklaces and bracelets.[8]:337 The smoke of burning giraffe skins was prescribed by the medicine men of Buganda as a cure for persistent nose bleeding.[8]:337 European explorers also hunted them.[29]:129 Habitat destruction has hurt the giraffe, too: in the Sahel, trees are cut down for firewood and to make way for livestock.[16] Normally, giraffes can coexist with livestock, since they feed in the trees above their heads.[16]

Overall, the giraffe is assessed as Least Concern from a conservation perspective by the International Union for Conservation of Nature (IUCN), as it still is widespread and occurs in numerous reserves.[2] However, giraffes have been extirpated from many parts of their former range, including Burkina Faso, Eritrea, Guinea, Malawi, Mauritania and Senegal.[2] They may also have disappeared from Angola, Mali and Nigeria.[2] Two subspecies, the West African giraffe and the Rothschild giraffe, have been classified as endangered,[2][24] as wild populations of each of them number in the hundreds.[17] In 1997, Jonathan Kingdon suggested that the Nubian giraffe was the most threatened of all giraffes;[15] as of 2010, it may number fewer than 250, but little recent information is available and consequently that estimate is the subject of considerable uncertainty.[17] While giraffe populations have declined in western Africa, they are stable and expanding in southern Africa thanks to private game reserves.[16] The giraffe is a protected species in most of its range. In 1999, the total wild giraffe population was estimated at over 140,000.[17] However, estimates in 2010 indicate that fewer than 80,000 remain.[17]

References

  1. ^ a b c Grubb, Peter (16 November 2005). "Giraffa camelopardalis". In Wilson, Don E., and Reeder, DeeAnn M., eds. Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Baltimore: Johns Hopkins University Press, 2 vols. (2142 pp.). p. 672. ISBN 978-0-8018-8221-0. OCLC 62265494. http://www.bucknell.edu/msw3/browse.asp?id=14200476. 
  2. ^ a b c d e f Fennessy, J.; Brown, D. (2008). Giraffa camelopardalis. In: IUCN 2008. IUCN Red List of Threatened Species. Downloaded on 2009-3-13.
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