The giraffe is a large African hoofed mammal belonging to the genus Giraffa. It is the tallest living terrestrial animal and the largest ruminant on Earth. It is classified under the family Giraffidae, along with its closest extant relative, the okapi. Traditionally, giraffes have been thought of as one species, Giraffa camelopardalis, with nine subspecies. Most recently, researchers proposed dividing them into four extant species, with seven subspecies, which can be distinguished morphologically by their fur Animal coat patterns. Six valid extinct species of Giraffa are known from the fossil record.
The giraffe's distinguishing characteristics are its extremely long neck and legs, horn-like , and spotted coat patterns. Its 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 and . Their food source is leaves, fruits, and flowers of woody plants, primarily Acacieae species, which they browse at heights most other ground-based cannot reach. , , , and African wild dogs may prey upon giraffes. Giraffes live in herds of related females and their offspring or bachelor herds of unrelated adult males but are gregarious and may gather in large groups. Males establish social hierarchies through "necking", combat bouts where the neck is used as a weapon. Dominant males gain mating access to females, which bear sole responsibility for rearing the young.
The giraffe has intrigued various ancient and modern cultures for its peculiar appearance and has often been featured in paintings, books, and cartoons. It is classified by the International Union for Conservation of Nature (IUCN) as vulnerable to extinction. It has been Local extinction from many parts of its former range. Giraffes are still found in many and , but estimates as of 2016 indicate there are approximately 97,500 members of Giraffa in the wild. More than 1,600 were kept in zoos in 2010.
"Camelopard" () is an archaism English name for the giraffe; it derives from the Ancient Greek καμηλοπάρδαλις (), from κάμηλος (), "camel", and πάρδαλις (), "leopard", referring to its camel-like shape and leopard-like colouration.
The family Giraffidae was once much more extensive, with over 10 fossil Genus described. The elongation of the neck appears to have started early in the giraffe lineage. Comparisons between giraffes and their ancient relatives suggest vertebrae close to the skull lengthened earlier, followed by lengthening of vertebrae further down. One early giraffid ancestor was Canthumeryx, which has been dated variously to have lived , 17–15 mya or 18–14.3 mya and whose deposits have been found in Libya. This animal resembled an antelope and had a medium-sized, lightly built body. Giraffokeryx appeared 15–12 mya on the Indian subcontinent and resembled an okapi or a small giraffe, and had a longer neck and similar . Giraffokeryx may have shared a clade with more massively built giraffids like Sivatherium and Bramatherium.
Giraffids like Palaeotragus, Shansitherium and Samotherium appeared 14 mya and lived throughout Africa and Eurasia. These animals had broader skulls with reduced frontal cavities. Paleotragus resembled the okapi and may have been its ancestor. Others find that the okapi lineage diverged earlier, before Giraffokeryx. Samotherium was a particularly important transitional fossil in the giraffe lineage, as the length and structure of its cervical vertebrae were between those of a modern giraffe and an okapi, and its neck posture was likely similar to the former's. Bohlinia, which first appeared in southeastern Europe and lived 9–7 mya, was likely a direct ancestor of the giraffe. Bohlinia closely resembled modern giraffes, having a long neck and legs and similar ossicones and dentition.
Bohlinia colonised China and northern India and produced the Giraffa, which, around , reached Africa. led to the extinction of the Asian giraffes, while the African giraffes survived and radiated into new species. Living giraffes appear to have arisen around in eastern Africa during the Pleistocene. Some biologists suggest the modern giraffes descended from Giraffa jumae; others find Giraffa gracilis a more likely candidate. G. jumae was larger and more robust, while G. gracilis was smaller and more slender.
The changes from extensive forests to more open , which began 8 mya, are believed to be the main driver for the evolution of giraffes. During this time, tropical plants disappeared and were replaced by arid C4 plants, and a dry savannah emerged across eastern and northern Africa and western India. Some researchers have hypothesised that this new habitat, coupled with a different diet, including acacia species, may have exposed giraffe ancestors to toxins that caused higher mutation rates and a higher rate of evolution. The coat patterns of modern giraffes may also have coincided with these habitat changes. Asian giraffes are hypothesised to have had more okapi-like colourations.
The giraffe genome is around 2.9 billion in length, compared to the 3.3 billion base pairs of the okapi. Of the proteins in giraffe and okapi genes, 19.4% are identical. The divergence of giraffe and okapi lineages dates to around 11.5 mya. A small group of in the giraffe appears responsible for the animal's height and associated circulatory adaptations.
Carl Linnaeus originally classified living giraffes as one species in 1758. He gave it the binomial name Cervus camelopardalis. Mathurin Jacques Brisson coined the generic name Giraffa in 1762. During the 1900s, various taxonomies with two or three species were proposed. A 2007 study on the genetics of giraffes using mitochondrial DNA suggested at least six lineages could be recognised as species. A 2011 study using detailed analyses of the morphology of giraffes, and application of the Species, described eight species of living giraffes. A 2016 study also concluded that living giraffes consist of multiple species. The researchers suggested the existence of four species, which have not exchanged genetic information between each other for one to two million years.
A 2020 study showed that, depending on the method chosen, different taxonomic hypotheses recognizing from two to six species can be considered for the genus Giraffa. That study also found that multi-species coalescent methods can lead to taxonomic over-splitting, as those methods delimit geographic structures rather than species. The three-species hypothesis, which recognises G. camelopardalis, G. giraffa, and G. tippelskirchi, is highly supported by Phylogenetics analyses and also corroborated by most population genetic and multi-species coalescent analyses. A 2021 whole genome sequencing study suggests the existence of four distinct species and seven subspecies, which was supported by a 2024 study of cranial morphology. A 2024 study found a higher amount of ancient gene flow than expected between populations.
The cladogram below shows the phylogenetic relationship between the four species and seven subspecies based on a 2021 genome analysis. The eight lineages correspond to eight traditional subspecies in the one-species hypothesis. The Rothschild giraffe is subsumed into G. camelopardalis camelopardalis.
The following table compares the different hypotheses for giraffe species. The description column shows the traditional nine subspecies in the one-species hypothesis.
The first extinct species to be described was Giraffa sivalensis from Pakistan, the holotype of which was reevaluated as a vertebra of separate species within the genus that was initially described as a fossil of the living giraffe. Another extinct species Giraffa punjabiensis is known from Pakistan. Four other valid extinct species of Giraffa known from Africa are Giraffa gracilis, Giraffa jumae, Giraffa pygmaea and Giraffa stillei. " G." pomeli from Algeria and Tunisia is not a species of Giraffinae, but a species of Palaeotraginae related to Mitilanotherium.
The Animal coat has dark blotches or patches, which can be orange, chestnut, brown, or nearly black, surrounded by light hair, usually white or cream coloured. Male giraffes become darker as they grow old. The coat pattern to serve as camouflage in the light and shade patterns of savannah woodlands. When standing among trees and bushes, they are hard to see at even a few metres distance. However, adult giraffes move about to gain the best view of an approaching predator, relying on their size and ability to defend themselves rather than on camouflage, which may be more important for calves. Each giraffe has a unique coat pattern. Calves inherit some coat pattern traits from their mothers, and variation in some spot traits is correlated with calf survival. The skin under the blotches may regulate the animal's body temperature, being sites for complex blood vessel systems and large . Spotless or solid-colour giraffes are very rare, but have been observed.
The fur may give the animal chemical defense, as its parasite repellents give it a characteristic scent. At least 11 main aromaticity chemicals are in the fur, although indole and 3-methylindole are responsible for most of the smell. Because males have a stronger odour than females, it may also have a sexual function.
With eyes located on the sides of the head, the giraffe has a broad visual field from its great height. Compared to other , giraffe vision is more binocular vision and the eyes are larger with a greater surface area. Giraffes may see in colour, and their senses of hearing and olfaction are sharp. The ears are movable. The nostrils are slit-shaped, possibly to withstand blowing sand. The giraffe's tongue is about long. It is black, perhaps to protect against sunburn, and can prehensile foliage and delicately pick off leaves. The upper lip is flexible and hairy to protect against sharp prickles. The upper jaw has a hard palate instead of front teeth. The molars and are wide with low crowns on the surface.
The giraffe's neck vertebrae have ball and socket joints. 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), unlike in most other ruminants, where the articulation is between the seventh cervical vertebra (C7) and T1. This allows C7 to contribute directly to increased neck length and has given rise to the suggestion that T1 is actually C8, and that giraffes have added an extra cervical vertebra. 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 characterised by increased neurological anomalies and maladies.
There are several hypotheses regarding the evolutionary origin and maintenance of elongation in giraffe necks. Charles Darwin originally suggested the "competing browsers hypothesis", which has been challenged only recently. It suggests that competitive pressure from smaller browsers, like 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 high, while even quite large competitors, such as kudu, can feed up to only about high. There is also research suggesting that browsing competition is intense at lower levels, and giraffes feed more efficiently (gaining more leaf biomass with each mouthful) high in the canopy. However, scientists disagree about just how much time giraffes spend feeding at levels beyond the reach of other browsers, and a 2010 study found that adult giraffes with longer necks actually suffered higher mortality rates under drought conditions than their shorter-necked counterparts. This study suggests that maintaining a longer neck requires more nutrients, which puts longer-necked giraffes at risk during a food shortage.
Another theory, the sexual selection hypothesis, proposes that long necks evolved as a secondary sexual characteristic, giving males an advantage in "necking" contests to establish dominance and obtain access to sexually receptive females. In support of this theory, some studies have stated that necks are longer and heavier for males than females of the same age, and that males do not employ other forms of combat. However, a 2024 study found that, while males have thicker necks, females actually have proportionally longer ones, which is likely because of their greater need to find more food to sustain themselves and their dependent young. It has also been proposed that the neck serves to give the animal greater vigilance.
A giraffe has only two : walking and galloping. Walking is done by moving the legs on one side of the body, then doing the same on the other side. When galloping, the hind legs move around the front legs before the latter move forward, and the tail will curl up. The movements of the head and neck provide balance and control momentum while galloping. The giraffe can reach a sprint speed of up to , and can sustain for several kilometres. Giraffes would probably not be competent swimmers as their long legs would be highly cumbersome in the water, although they might be able to float. When swimming, the thorax would be weighed down by the front legs, making it difficult for the animal to move its neck and legs in harmony or keep its head above the water's surface.
A giraffe rests by lying with its body on top of its folded legs. 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 front knees and positions its backside on top of its hindlegs. It then pulls the backside upwards, and the front legs stand straight up again. At each stage, the animal swings its head for balance. If the giraffe wants to reach down to drink, it either spreads its front legs or bends its knees. Studies in captivity found the giraffe sleeps intermittently around 4.6 hours per day, mostly at night. It usually sleeps lying down; however, standing sleeps have been recorded, particularly in older individuals. Intermittent short "deep sleep" phases while lying are characterised by the giraffe bending its neck backwards and resting its head on the hip or thigh, a position believed to indicate paradoxical sleep.
Giraffes have Esophagus that are strong enough to allow regurgitation of food from the stomach up the neck and into the mouth for . They have four-chambered stomachs, which are adapted to their specialized diet. The of an adult giraffe measure more than in length and have a relatively small ratio of small intestine to large intestine. The giraffe has a small, compact liver. In fetuses there may be a small gallbladder that vanishes before birth.
During the wet season, food is abundant and giraffes are more spread out, while during the dry season, they gather around the remaining evergreen trees and bushes. Mothers tend to feed in open areas, presumably to make it easier to detect predators, although this may reduce their feeding efficiency. 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. 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. The animal's faeces come in the form of small pellets. When it has access to water, a giraffe will go no more than three days without drinking.
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 particularly tall trees. Feeding is at its highest during the first and last hours of daytime. Between these hours, giraffes mostly stand and ruminate. Rumination is the dominant activity during the night, when it is mostly done lying down.
The number of giraffes in a group can range from one up to 66 individuals. Giraffe groups tend to be sex-segregated although mixed-sex groups made of adult females and young males also occur. Female groups may be matrilineally related. Generally, females are more selective than males when deciding which individuals of the same sex they associate with. Particularly stable giraffe groups are those made of mothers and their young, which can last weeks or months. Young males also form groups and will engage in playfights. However, as they get older, males become more solitary but may also associate in pairs or with female groups. Giraffes are not territorial, but they have that vary according to rainfall and proximity to human settlements. Male giraffes occasionally roam far from areas that they normally frequent.
Early biologists suggested giraffes were mute and unable to create enough air flow to vibrate their . This has been proved to the contrary; they have been recorded to communicate using snorts, sneezes, coughs, snores, hisses, bursts, moans, grunts, growls and flute-like sounds. During courtship, males emit loud coughs. Females call their young by bellowing. Calves will emit bleats, mooing and mewing sounds. Snorting and hissing is associated with vigilance. During nighttime, giraffes appear to humming to each other. There is some evidence that giraffes use Helmholtz resonance to create infrasound. They also communicate with body language. Dominant males display to other males with an erect posture; holding the chin and head up while walking stiffly and displaying their side. The less dominant show submissiveness by dropping the head and ears, lowering the chin and fleeing.
Male giraffes assess female fertility by tasting the female's urine to detect oestrus, in a multi-step process known as the flehmen response. Once an oestrous female is detected, the male will attempt to court her. When courting, dominant males will keep subordinate ones at bay. A courting male may lick a female's tail, lay his head and neck on her body or nudge her with his ossicones. During copulation, the male stands on his hind legs with his head held up and his front legs resting on the female's sides.
Giraffe gestation lasts 400–460 days, after which a single calf is normally born, although twins occur on rare occasions. The mother gives birth standing up. The calf emerges head and front legs first, having broken through the , and falls to the ground, severing the umbilical cord. A newborn giraffe is 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 one to three weeks, it spends most of its time hiding, its coat pattern providing camouflage. The ossicones, which have lain flat in the womb, raise up in a few days.
Mothers with calves will gather in nursery herds, moving or browsing together. Mothers in such a group may sometimes leave their calves with one female while they forage and drink elsewhere. This is known as a "calving pool". Calves are at risk of predation, and a mother giraffe will stand over them and kick at an approaching predator. Females watching calving pools will only alert their own young if they detect a disturbance, although the others will take notice and follow. Allo-sucking, where a calf will suckle a female other than its mother, has been recorded in both wild and captive giraffes. Calves first ruminate at four to six months and stop lactation at six to eight months. Young may not reach independence until they are 14 months old. Females are able to reproduce at four years of age, while spermatogenesis in males begins at three to four years of age. Males must wait until they are at least seven years old to gain the opportunity to mate.
After a duel, it is common for two male giraffes to caress and court each other. Such interactions between males have been found to be more frequent than heterosexual coupling. In one study, up to 94 percent of observed mounting incidents took place between males. The proportion of same-sex activities varied from 30 to 75 percent. Only one percent of same-sex mounting incidents occurred between females.
The local, seasonal presence of large herds of migratory and reduces predation pressure on giraffe calves and increases their survival probability. In turn, it has been suggested that other ungulates may benefit from associating with giraffes, as their height allows them to spot predators from further away. Zebras were found to assess predation risk by watching giraffes and spend less time looking around when giraffes are present.
Some parasites feed on giraffes. They are often hosts for , especially in the area around the genitals, which have thinner skin than other areas. Tick species that commonly feed on giraffes are those of genera Hyalomma, Amblyomma and Rhipicephalus. Red-billed and yellow-billed oxpeckers clean giraffes of ticks and alert them to danger. Giraffes host numerous species of internal parasites and are susceptible to various diseases. They were victims of the (now eradicated) viral illness rinderpest. Giraffes can also suffer from a skin disorder, which comes in the form of wrinkles, lesions or raw skin fissure. As much as 79% of giraffes have symptoms of the disease in Ruaha National Park, but it did not cause mortality in Tarangire and is less prevalent in areas with fertile soils.
Giraffes have a presence in modern Western culture. Salvador Dalí depicted them with burning manes in some surrealist paintings. Dali considered the giraffe to be a masculine symbol. A flaming giraffe was meant to be a "masculine cosmic apocalyptic monster". Several children's books feature the giraffe, including David A. Ufer's The Giraffe Who Was Afraid of Heights, Giles Andreae's Giraffes Can't Dance and Roald Dahl's The Giraffe and the Pelly and Me. Giraffes have appeared in animated films as minor characters in Disney's Dumbo and The Lion King, and in more prominent roles in The Wild and the Madagascar films. Sophie the Giraffe has been a popular teether since 1961. Another famous fictional giraffe is the Toys "R" Us mascot Geoffrey the Giraffe.
The giraffe has also been used for some scientific experiments and discoveries. Scientists have used the properties of giraffe skin as a model for space suit and flight suit because the people in these professions are in danger of passing out if blood rushes to their legs. Computer scientists have modeled the coat patterns of several subspecies using reaction–diffusion mechanisms.
Individual captive giraffes were given celebrity status throughout history. In 1414, a giraffe from Malindi was Treasure voyages 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. The Medici giraffe was a giraffe presented to Lorenzo de' Medici in 1486. It caused a great stir on its arrival in Florence. Zarafa, another famous giraffe, was brought from Egypt to Paris in the early 19th century as a gift for Charles X of France. A sensation, the giraffe was the subject of numerous memorabilia or "giraffanalia".
Giraffes have become popular attractions in modern , though keeping them is difficult as they prefer large areas and need to eat large amounts of browse. Captive giraffes in North America and Europe appear to have a higher mortality rate than in the wild, the most common causes being poor husbandry, nutrition, and management. Giraffes in zoos display stereotypical behaviours, particularly the licking of inanimate objects and pacing. Zookeepers may offer various activities to stimulate giraffes, including training them to take food from visitors. for giraffes are built particularly high to accommodate their height.
Protected areas like national parks provide important habitat and anti-poaching protection to giraffe populations. Community-based conservation efforts outside national parks are also effective at protecting giraffes and their habitats. Private game reserves have contributed to the preservation of giraffe populations in eastern and southern Africa. The giraffe is a protected species in most of its range. It is the national animal of Tanzania, and is protected by law, and unauthorised killing can result in imprisonment. The UN-backed Convention of Migratory Species selected giraffes for protection in 2017. In 2019, giraffes were listed under Appendix II of the Convention on International Trade in Endangered Species (CITES), which means international trade including in parts/derivatives is regulated.
Translocations are sometimes used to augment or re-establish diminished or extirpated populations, but these activities are risky and difficult to undertake using the best practices of extensive pre- and post-translocation studies and ensuring a viable founding population. Aerial survey is the most common method of monitoring giraffe population trends in the vast roadless tracts of African landscapes, but aerial methods are known to undercount giraffes. Ground-based survey methods are more accurate and can be used in conjunction with aerial surveys to make accurate estimates of population sizes and trends.
Species and subspecies
Anatomy
Head
Neck
Legs, locomotion and posture
Internal systems
Behaviour and ecology
Habitat and feeding
Social life
Reproduction and parental care
Necking
Mortality and health
Human relations
Cultural significance
Captivity
Exploitation
Conservation status
See also
External links
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