Giraffe

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Giraffes
Temporal range: 11.61–0 
Ma
Miocene to Recent
Masai giraffe (G. c. tippelskirchi) in Mikumi National Park, Tanzania

Vulnerable  (IUCN 3.1)[1] (As the species complex)
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Family: Giraffidae
Genus: Giraffa
Brisson, 1762
Species:
G. camelopardalis
Binomial name
Giraffa camelopardalis
Linnaeus, 1758
Species

See taxonomy

Distribution of the giraffe

The giraffe is a large African

Giraffa camelopardalis, with nine subspecies. Most recently, researchers proposed dividing them into up to eight extant species due to new research into their mitochondrial and nuclear DNA
, and individual species can be distinguished by their fur coat patterns. Seven other extinct species of Giraffa are known from the fossil record.

The giraffe's chief distinguishing characteristics are its extremely long neck and legs, its horn-like

acacia
species, which they browse at heights most other herbivores cannot reach.

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 and has been extirpated from many parts of its former range. Giraffes are still found in numerous national parks and game reserves, 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.

Etymology

The name "giraffe" has its earliest known origins in the

Arabic word zarāfah (زرافة),[2] ultimately from Persian زُرنَاپَا‎ (zurnāpā), a compound of زُرنَا‎ (zurnā, "flute, zurna") and پَا‎ (, "leg").[3][4] In early Modern English the spellings jarraf and ziraph were used, probably directly from the Arabic,[5] and in Middle English jarraf and ziraph, gerfauntz. The Italian form giraffa arose in the 1590s. The modern English form developed around 1600 from the French girafe.[2]

"Camelopard" /kəˈmɛləˌpɑːrd/ is an archaic English name for the giraffe; it derives from the Ancient Greek καμηλοπάρδαλις (kamēlopárdalis), from κάμηλος (kámēlos), "camel", and πάρδαλις (párdalis), "leopard", referring to its camel-like shape and leopard-like colouration.[6][7]

Taxonomy

Evolution

The giraffe is one of only two living genera of the family Giraffidae in the order

sister taxon to Antilocapridae, with an estimated split of over 20 million years ago.[9]

Ruminantia

The family Giraffidae was once much more extensive, with over 10 fossil

ossicones.[8] Giraffokeryx may have shared a clade with more massively built giraffids like Sivatherium and Bramatherium.[10]

The extinct giraffid Samotherium (middle) in comparison with the okapi (below) and giraffe. The anatomy of Samotherium appears to have shown a transition to a giraffe-like neck.[11]

Giraffids like Palaeotragus, Shansitherium and Samotherium appeared 14 mya and lived throughout Africa and Eurasia. These animals had broader skulls with reduced frontal cavities.[8][10] Paleotragus resembled the okapi and may have been its ancestor.[8] Others find that the okapi lineage diverged earlier, before Giraffokeryx.[10] 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.[11] 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.[8]

Bohlinia colonised China and northern India and produced the Giraffa, which, around 7 million years ago, reached Africa.

Climate changes 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 1 million years ago in eastern Africa during the Pleistocene.[8] Some biologists suggest the modern giraffes descended from G. jumae;[12] others find G. gracilis a more likely candidate. G. jumae was larger and more robust, while G. gracilis was smaller and more slender.[8]

The changes from extensive forests to more open habitats, which began 8 mya, are believed to be the main driver for the evolution of giraffes.

savannah emerged across eastern and northern Africa and western India.[13][14] 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.[15] 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.[8]

The giraffe

regulatory genes in the giraffe appear to be responsible for the animal's height and associated circulatory adaptations.[16][17]

Species and subspecies

paraphyletic haplotypes found in Maasai and reticulated giraffes".[18]

The International Union for Conservation of Nature (IUCN) currently recognises only one species of giraffe with nine subspecies.[1]

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.[19] During the 1900s, various taxonomies with two or three species were proposed.[20] A 2007 study on the genetics of giraffes using mitochondrial DNA suggested at least six lineages could be recognised as species.[18] A 2011 study using detailed analyses of the morphology of giraffes, and application of the phylogenetic species concept, described eight species of living giraffes.[21] 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 1 to 2 million years.[22]

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 phylogenetic analyses and also corroborated by most population genetic and multi-species coalescent analyses.[23] A 2021 whole genome sequencing study suggests the existence of four distinct species and seven subspecies.[24] A 2024 study found a higher amount of ancient gene flow than expected between populations.[25]

The cladogram below shows the phylogenetic relationship between the four proposed species and seven subspecies based on a 2021 genome analysis.[24] Note the eight lineages correspond to eight of the 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.[1][26]

Species and subspecies of giraffe
Description Image Eight species taxonomy[21] Four species taxonomy[22][24] Three species taxonomy[23]
The
European zoos were shown to be, in fact, G. c. antiquorum.[27] With this correction, about 65 are living in zoos.[29]
Kordofan giraffe
(G. antiquorum)[30]
Northern giraffe
(G. camelopardalis)
Three or four subspecies:
  • G. c. antiquorum
  • G. c. camelopardalis
  • G. c. peralta
  • G. c. reticulata (only in three-species hypothesis)
The Nubian giraffe (G. c. camelopardalis), is found in eastern South Sudan and southwestern Ethiopia, in addition to Kenya and Uganda.[1] It has sharp-edged chestnut-coloured spots surrounded by mostly white lines, while undersides lack spotting. A lump is prominent in the middle of the male's head.[28]: 51  Around 2,150 are thought to remain in the wild, with another 1,500 individuals belonging to the Rothschild's ecotype.[1] With the addition of Rothschild's giraffe to the Nubian subspecies, the Nubian giraffe is very common in captivity, although the original phenotype is rare — a group is kept at Al Ain Zoo in the United Arab Emirates.[31] In 2003, this group numbered 14.[32] Nubian giraffe
(G. camelopardalis)[26]

Also known as Baringo giraffe or Ugandan giraffe

Two subspecies:
  • G. c. camelopardalis
  • G. c. rothschildi (Rothschild's giraffe)
Rothschild's giraffe (G. c. rothschildi) may be an ecotype of G. camelopardalis. Its range includes parts of Uganda and Kenya.[1] Its presence in South Sudan is uncertain.[33] This giraffe has large dark patches whose edges are normally well-defined but sometimes split. The dark spots may also have swirls of pale colour within them. Spotting rarely reaches below the hocks and almost never to the hooves. This ecotype may also develop five "horns".[28]: 53  Around 1,500 individuals are believed to remain in the wild,[1] and more than 450 are living in zoos.[29] According to genetic analysis circa September 2016, it is conspecific with the Nubian giraffe (G. c. camelopardalis).[22]
The
pelage (fur) than other subspecies,[34]: 322  with red lobe-shaped blotches that reach under the hocks. The ossicones are more erect than in other subspecies and males have well-developed median lumps.[28]: 52–53  It is the most endangered subspecies within Giraffa, with 400 individuals remaining in the wild.[1] Giraffes in Cameroon were formerly believed to belong to this species, but are actually G. c. antiquorum. 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 are actually G. c. antiquorum. The same 2007 study found that the West African giraffe was more closely related to Rothschild's giraffe than the Kordofan, and its ancestor may have migrated from eastern to northern Africa and then west as the Sahara Desert spread. At its largest, Lake Chad may have acted as a boundary between the West African and Kordofan giraffes during the Holocene (before 5000 BC).[27]
West African giraffe
(G. peralta),[35]

Also known as Niger giraffe or Nigerian giraffe

The
International Species Information System records, more than 450 are living in zoos.[29] A 2024 study found that the reticulated giraffe is actually the result of hybridisation between northern and southern giraffe lineages.[25]
Reticulated giraffe
(G. reticulata),[36]

Also known as Somali giraffe

The
Namib Desert and Etosha National Park populations form a separate subspecies.[41] This subspecies is white with large brown blotches with pointed or cut edges. The spotting pattern extends throughout the legs but not the upper part of the face. The neck and rump patches tend to be fairly small. The subspecies also has a white ear mark.[28]: 51  About 13,000 animals are estimated to remain in the wild,[1] and about 20 are living in zoos.[29]
Angolan giraffe
(G. angolensis)

Also known as Namibian giraffe

Southern giraffe (G. giraffa)
Two subspecies:
  • G. g. angolensis
  • G. g. giraffa
The South African giraffe (G. c. giraffa) is found in northern South Africa, southern Botswana, northern Botswana and southwestern Mozambique.[1][39][40] It has a tawny background colour marked with dark, somewhat rounded patches "with some fine projections". The spots extend down the legs, growing smaller as they do. The median lump of males is relatively small.[28]: 52  A maximum of 31,500 are estimated to remain in the wild,[1] and around 45 are living in zoos.[29] South African giraffe
(G. giraffa)[42]

Also known as Cape giraffe

The Masai giraffe (G. c. tippelskirchi) can be found in central and southern Kenya and in Tanzania.[1] Its coat patterns are highly diverse, with spots ranging from mostly rounded and smooth edged to oval shaped and incised or loped edged.[43] A median lump is usually present in males.[28]: 54 [44] A total of 32,550 are thought to remain in the wild,[1] and about 100 are living in zoos.[29] Masai giraffe
(G. tippelskirchi)[37]

Also known as

Kilimanjaro
giraffe

Masai giraffe (G. tippelskirchi)
Two subspecies:
  • G. t. tippelskirchi
  • G. t. thornicrofti
Thornicroft's giraffe (G. c. thornicrofti) is restricted to the Luangwa Valley in eastern Zambia.[1] It has notched and somewhat star-shaped patches which and may or may not extend across the legs. The median lump of males is modestly sized.[28]: 54  No more than 550 remain in the wild,[1] with none in zoos.[29] It was named after Harry Scott Thornicroft.[37]
Thornicroft's giraffe

("G. thornicrofti")

Also known as Luangwa giraffe or Rhodesian giraffe

The first extinct species to be described was Giraffa sivalensis Falconer and Cautley 1843, a reevaluation of a vertebra that was initially described as a fossil of the living giraffe.[45] While taxonomic opinion may be lacking on some names, the extinct species that have been published include:[46]

Anatomy

Photograph of a Giraffe skeleton
Giraffe skeleton on display at the Museum of Osteology, Oklahoma City

Fully grown giraffes stand 4.3–5.7 m (14–19 ft) tall, with males taller than females.[47] The average weight is 1,192 kg (2,628 lb) for an adult male and 828 kg (1,825 lb) for an adult female.[48] Despite its long neck and legs, its body is relatively short.[49]: 66  The skin is mostly gray,[48] or tan,[50] and can reach a thickness of 20 mm (0.79 in).[51]: 87  The 80–100 cm (31–39 in) long[37] tail ends in a long, dark tuft of hair and is used as a defense against insects.[51]: 94 

The coat has dark blotches or patches, which can be orange, chestnut, brown, or nearly black, surrounded by light hair, usually white or cream coloured.[52] Male giraffes become darker as they grow old.[44] The coat pattern has been claimed to serve as camouflage in the light and shade patterns of savannah woodlands.[37] 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.[8] Each giraffe has a unique coat pattern.[53][54] Calves inherit some coat pattern traits from their mothers, and variation in some spot traits is correlated with calf survival.[43] The skin under the blotches may regulate the animal's body temperature, being sites for complex blood vessel systems and large sweat glands.[55] Spotless, or solid-color giraffes are very rare but have been observed.[56][57]

The fur may give the animal chemical defense, as its parasite repellents give it a characteristic scent. At least 11 main

3-methylindole are responsible for most of the smell. Because males have a stronger odour than females, it may also have a sexual function.[58]

Head

Closeup photograph of a giraffe head
Closeup of the head of a northern giraffe

Both sexes have prominent horn-like structures called

vascularised, the ossicones may have a role in thermoregulation,[55] and are used in combat between males.[59] Appearance is a reliable guide to the sex or age of a giraffe: the ossicones of females and young are thin and display tufts of hair on top, whereas those of adult males tend to be bald and knobbed on top.[44] A lump, which is more prominent in males, emerges in the middle of the skull.[19] Males develop calcium deposits that form bumps on their skulls as they age.[52] Multiple sinuses lighten a giraffe's skull.[51]: 103  However, as males age, their skulls become heavier and more club-like, helping them become more dominant in combat.[44] The occipital condyles at the bottom of the skull allow the animal to tip its head over 90 degrees and grab food on the branches directly above them with the tongue.[51]: 103, 110 [19]

With eyes located on the sides of the head, the giraffe has a broad

grasp foliage and delicately pick off leaves.[51]: 109–110  The upper lip is flexible and hairy to protect against sharp prickles.[19] The upper jaw has a hard palate instead of front teeth. The molars and premolars are wide with low crowns on the surface.[51]
: 106 

Neck

The giraffe has an extremely elongated neck, which can be up to 2.4 m (7 ft 10 in) in length.[62] Along the neck is a mane made of short, erect hairs.[19] The neck typically rests at an angle of 50–60 degrees, though juveniles are closer to 70 degrees.[51]: 72–73  The long neck results from a disproportionate lengthening of the cervical vertebrae, not from the addition of more vertebrae. Each cervical vertebra is over 28 cm (11 in) long.[49]: 71  They comprise 52–54 per cent of the length of the giraffe's vertebral column, compared with the 27–33 percent typical of similar large ungulates, including the giraffe's closest living relative, the okapi.[15] This elongation largely takes place after birth, perhaps because giraffe mothers would have a difficult time giving birth to young with the same neck proportions as adults.[63] The giraffe's head and neck are held up by large muscles and a nuchal ligament, which are anchored by long thoracic vertebrae spines, giving them a hump.[19][64][37]

Photograph of an adult male giraffe with its next fully extended feeding on an acacia
Adult male reticulated giraffe feeding high on an acacia, in Kenya

The giraffe's neck vertebrae have

ball and socket joints.[49]: 71  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.[15][63] 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.[64] 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.[15]

There are several hypotheses regarding the evolutionary origin and maintenance of elongation in giraffe necks.

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 4.5 m (15 ft) high, while even quite large competitors, such as kudu, can feed up to only about 2 m (6 ft 7 in) high.[65] 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.[66][67] However, scientists disagree about just how much time giraffes spend feeding at levels beyond the reach of other browsers,[12][59][65][68]
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.[69]

Another theory, the sexual selection hypothesis, proposes 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][59] and males do not employ other forms of combat.[12] However, one objection is it fails to explain why female giraffes also have long necks.[70] It has also been proposed that the neck serves to give the animal greater vigilance.[71][72]

Legs, locomotion and posture

Photograph of giraffe's hind leg
Right hind leg of a Masai giraffe at San Diego Zoo

A giraffe's front and back legs are about the same length. 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.[73] It appears that a suspensory ligament allows the lanky legs to support the animal's great weight.[74] The hooves of large male giraffes reach 31 cm × 23 cm (12.2 in × 9.1 in) in diameter.[51]: 98  The fetlock of the leg is low to the ground, allowing the hoof to better support the animal's weight. Giraffes lack dewclaws and interdigital glands. While the pelvis is relatively short, the ilium has stretched out crests.[19]

A giraffe has only two gaits: walking and galloping. Walking is done by moving the legs on one side of the body, then doing the same on the other side.[44] When galloping, the hind legs move around the front legs before the latter move forward,[52] and the tail will curl up.[44] The movements of the head and neck provide balance and control momentum while galloping.[34]: 327–29  The giraffe can reach a sprint speed of up to 60 km/h (37 mph),[75] and can sustain 50 km/h (31 mph) for several kilometres.[76] Giraffes would probably not be competent swimmers as their long legs would be highly cumbersome in the water,[77] although they might be able to float.[78] 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[77][78] or keep its head above the water's surface.[77]

A juvenile giraffe walking in Malawi.

A giraffe rests by lying with its body on top of its folded legs.

paradoxical sleep.[79]

Internal systems

Sketch of the path of the recurrent laryngeal nerve in giraffe
Scheme of path of the recurrent laryngeal nerve in giraffe

In mammals, the left recurrent laryngeal nerve is longer than the right; in the giraffe, it is over 30 cm (12 in) longer. These nerves are longer in the giraffe than in any other living animal;[80] the left nerve is over 2 m (6 ft 7 in) long.[81] 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 (16 ft) in the largest giraffes.[80] Despite its long neck and large skull, the brain of the giraffe is typical for an ungulate.[82] Evaporative heat loss in the nasal passages keep the giraffe's brain cool.[55] The shape of the skeleton gives the giraffe a small lung volume relative to its mass. Its long neck gives it a large amount of dead space, in spite of its narrow windpipe. The giraffe also has a high tidal volume so the balance of dead space and tidal volume is much the same as other mammals. The animal can still provide enough oxygen for its tissues, and it can increase its respiratory rate and oxygen diffusion when running.[83]

Photograph of a giraffe bending down to drink
Reticulated giraffe bending down to drink in Kenya. The circulatory system is adapted to deal with blood flow rushing down its neck.

The giraffe's

right atrium while the head is lowered.[85] 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 skin of the lower legs is thick and tight, preventing too much blood from pouring into them.[37]

Giraffes have oesophageal muscles that are strong enough to allow regurgitation of food from the stomach up the neck and into the mouth for rumination.[49]: 78  They have four chambered stomachs, which are adapted to their specialized diet.[19] The intestines of an adult giraffe measure more than 70 m (230 ft) in length and have a relatively small ratio of small to large intestine.[86] The giraffe has a small, compact liver.[49]: 76  In fetuses there may be a small gallbladder that vanishes before birth.[19][87][88]

Behaviour and ecology

Habitat and feeding

A Masai giraffe extending its tongue to feed, in Tanzania.
A giraffe in Malawi eating leaves from a tree

Giraffes usually inhabit savannahs and open

Acacieae, Commiphora, Combretum and Terminalia tree over Brachystegia which are more densely spaced.[34]: 322  The Angolan giraffe can be found in desert environments.[89] Giraffes browse on the twigs of trees, preferring those of the subfamily Acacieae and the genera Commiphora and Terminalia,[90] which are important sources of calcium and protein to sustain the giraffe's growth rate.[8] They also feed on shrubs, grass and fruit.[34]: 324  A giraffe eats around 34 kg (75 lb) of plant matter daily.[44] When stressed, giraffes may chew on large branches, stripping them of bark.[34]: 325  Giraffes are also recorded to chew old bones.[51]
: 102 

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.[90] Mothers tend to feed in open areas, presumably to make it easier to detect predators, although this may reduce their feeding efficiency.[68] 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.[49]: 78–79  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.[90] The animal's faeces come in the form of small pellets.[19] When it has access to water, a giraffe will go no more than three days without drinking.[44]

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 too 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.[44]

Social life

Photograph of a gathering of four female giraffes
Gathering of female South African giraffes in Tswalu Kalahari Reserve, South Africa. These animals commonly gather in herds.

Giraffes usually form groups that vary in size and composition according to ecological, anthropogenic, temporal, and social factors.[91] Traditionally, the composition of these groups had been described as open and ever-changing.[92] 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".[93] More recent studies have found that giraffes have long lasting social groups or cliques based on kinship, sex or other factors, and these groups regularly associate with other groups in larger communities or sub-communities within a fission–fusion society.[94][95][96][97] Proximity to humans can disrupt social arrangements.[94] Masai giraffes in Tanzania sort themselves into different subpopulations of 60–90 adult females with overlapping ranges, each of which differ in reproductive rates and calf mortality.[98] Dispersal is male biased, and can include spatial and/or social dispersal.[99] Adult female subpopulations are connected by males into supercommunities of around 300 animals.[100]

The number of giraffes in a group can range from one up to 66 individuals.

matrilineally related.[97] Generally females are more selective than males in who they associate with regarding individuals of the same sex.[96] Particularly stable giraffe groups are those made of mothers and their young,[93] which can last weeks or months.[101] 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.[97][101] Giraffes are not territorial,[19] but they have home ranges that vary according to rainfall and proximity to human settlements.[102] Male giraffes occasionally roam far from areas that they normally frequent.[34]
: 329 

Early biologists suggested giraffes were mute and unable to create enough air flow to vibrate their

vocal folds.[103] To the contrary; they have been recorded to communicate using snorts, sneezes, coughs, snores, hisses, bursts, moans, grunts, growls and flute-like sounds.[44][103] During courtship, males emit loud coughs. Females call their young by bellowing. Calves will emit bleats, mooing and mewing sounds.[44] Snorting and hissing is associated with vigilance.[104] During nighttime, giraffes appear to hum to each other.[105] There is some evidence that giraffes use Helmholtz resonance to create infrasound.[106] 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.[44]

Reproduction and parental care

Photograph of giraffes mating
Angolan giraffes mating in Namibia

Reproduction in giraffes is broadly

oestrus cycling approximately every 15 days.[107][108] Female giraffes in oestrous are dispersed over space and time, so reproductive adult males adopt a strategy of roaming among female groups to seek mating opportunities, with periodic hormone-induced rutting behaviour approximately every two weeks.[109] Males prefer young adult females over juveniles and older adults.[93]

Male giraffes assess female fertility by tasting the female's urine to detect oestrus, in a multi-step process known as the flehmen response.[93][101] Once an oestrous female is detected, the male will attempt to court her. When courting, dominant males will keep subordinate ones at bay.[101] 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.[44]

Giraffe

fetal membranes, and falls to the ground, severing the umbilical cord.[19] A newborn giraffe is 1.7–2 m (5 ft 7 in – 6 ft 7 in) tall.[47] 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,[110] its coat pattern providing camouflage. The ossicones, which have lain flat in the womb, raise up in a few days.[44]

A female giraffe with her calf
Female Angolan giraffe with calf

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".[110] Calves are at risk of predation, and a mother giraffe will stand over them and kick at an approaching predator.[44] Females watching calving pools will only alert their own young if they detect a disturbance, although the others will take notice and follow.[110] Allo-sucking, where a calf will suckle a female other than its mother, has been recorded in both wild and captive giraffes.[111][112] Calves first ruminate at four to six months and stop nursing at six to eight months. Young may not reach independence until they are 14 months old.[51]: 49  Females are able to reproduce at four years of age,[44] while spermatogenesis in males begins at three to four years of age.[113] Males must wait until they are at least seven years old to gain the opportunity to mate.[44]

Necking

Photograph of two male giraffes necking to establish dominance
Here, male South African giraffes engage in low intensity necking to establish dominance, in Ithala Game Reserve, Kwa-Zulu-Natal, South Africa.

Male giraffes use their necks as weapons in combat, a behaviour known as "necking". Necking is used to establish dominance and males that win necking bouts have greater reproductive success.[12] This behaviour occurs at low or high intensity. In low-intensity necking, the combatants rub and lean on each other. The male that can keep itself more upright wins the bout. In high-intensity necking, the combatants will spread their front legs and swing their necks at each other, attempting to land blows with their ossicones. The contestants will try to dodge each other's blows and then prepare to counter. The power of a blow depends on the weight of the skull and the arc of the swing.[44] A necking duel can last more than half an hour, depending on how well matched the combatants are.[34]: 331  Although most fights do not lead to serious injury, there have been records of broken jaws, broken necks, and even deaths.[12]

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.[114] 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.[115]

Mortality and health

Photograph of a lioness with at an adult giraffe kill
Lioness seen with an adult Masai giraffe kill

Giraffes have high adult survival probability,

leopards, spotted hyenas and wild dogs.[52] A quarter to a half of giraffe calves reach adulthood.[116][119] Calf survival varies according to the season of birth, with calves born during the dry season having higher survival rates.[120]

The local, seasonal presence of large herds of migratory wildebeests and zebras reduces predation pressure on giraffe calves and increases their survival probability.[121] 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.[122]

Red-billed oxpeckers on a giraffe, Zambia

Some parasites feed on giraffes. They are often hosts for

lesions or raw fissures. 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.[123][124][125]

Human relations

Cultural significance

With its lanky build and spotted coat, the giraffe has been a source of fascination throughout human history, and its image is widespread in culture. It has represented flexibility, far-sightedness, femininity, fragility, passivity, grace, beauty and the continent of Africa itself.[126]: 7, 116 

Photograph of a giraffe painted on a rock face
San rock art in Namibia depicting a giraffe

Giraffes were depicted in art throughout the African continent, including that of the

Old Egyptian and 'mmy' in later periods.[126]
: 49 

Giraffes have a presence in modern

Disney's The Lion King and Dumbo, 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.[126]
: 127 

The giraffe has also been used for some scientific experiments and discoveries. Scientists have used the properties of giraffe skin as a model for

Mimosa forming a male, and Gacrux and Delta Crucis forming the female.[130]

Photograph of a painting of a giraffe and a man holding its leash
Painting of a giraffe imported to China during the Ming dynasty

Captivity

The Egyptians were among the earliest people to keep giraffes in captivity and shipped them around the Mediterranean.

displayed by the Romans. The first one in Rome was brought in by Julius Caesar in 46 BC.[126]: 52  With the fall of the Western Roman Empire, the housing of giraffes in Europe declined.[126]: 54  During the Middle Ages, giraffes were known to Europeans through contact with the Arabs, who revered the giraffe for its peculiar appearance.[52]

Individual captive giraffes were given celebrity status throughout history. In 1414, a giraffe from

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.[126]: 56  The Medici giraffe was a giraffe presented to Lorenzo de' Medici in 1486. It caused a great stir on its arrival in Florence.[131] 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".[126]
: 81 

Giraffes have become popular attractions in modern zoos, though keeping them healthy is difficult as they require vast 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.[51]: 153  Giraffes in zoos display stereotypical behaviours, particularly the licking of inanimate objects and pacing.[51]: 164  Zookeepers may offer various activities to stimulate giraffes, including training them to take food from visitors.[51]: 167, 176  Stables for giraffes are built particularly high to accommodate their height.[51]: 183 

Exploitation

Giraffes were probably common targets for hunters throughout Africa.

Humr people of Kordofan consume the drink Umm Nyolokh, which is prepared from the liver and bone marrow of giraffes. Richard Rudgley hypothesised that Umm Nyolokh might contain DMT.[132] The drink is said to cause hallucinations of giraffes, believed to be the giraffes' ghosts, by the Humr.[133]

Conservation status

In 2016, giraffes were assessed as

Koure
, Niger

The primary causes for giraffe population declines are habitat loss and direct killing for bushmeat markets. Giraffes have been extirpated from much of their historic range, including Eritrea, Guinea, Mauritania and Senegal.[1] They may also have disappeared from Angola, Mali, and Nigeria, but have been introduced to Rwanda and Eswatini.[1][139] As of 2010, there were more than 1,600 in captivity at Species360-registered zoos.[29] Habitat destruction has hurt the giraffe. In the Sahel, the need for firewood and grazing room for livestock has led to deforestation. Normally, giraffes can coexist with livestock, since they avoid direct competition by feeding above them.[37] In 2017, severe droughts in northern Kenya led to increased tensions over land and the killing of wildlife by herders, with giraffe populations being particularly hit.[140]

Protected areas like national parks provide important habitat and anti-poaching protection to giraffe populations.

national animal of Tanzania,[143] and is protected by law,[144] and unauthorised killing can result in imprisonment.[145] The UN backed Convention of Migratory Species selected giraffes for protection in 2017.[146] 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.[147]

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.[148][149] 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.[150]

See also

References

  1. ^ . Retrieved 12 November 2021.
  2. ^ a b "Giraffe". Online Etymology Dictionary. Archived from the original on 19 March 2015. Retrieved 1 November 2011.
  3. ^ Dehkhoda, Ali-akbar. "زراف". Dehkhoda Lexicon Institute and International Center for Persian Studies. Archived from the original on 28 December 2022. Retrieved 28 December 2022.
  4. ^ Ačaṙean, Hračʿeay (1973). "զուրափէ" [in Hayerēn armatakan baṙaran [Armenian Etymological Dictionary] (in Armenian), volume II, 2nd edition, a reprint of the original 1926–1935 seven-volume edition]. www.nayiri.com. Yerevan: University Press. p. 110a. Archived from the original on 28 December 2022. Retrieved 28 December 2022.
  5. from the original on 22 September 2023. Retrieved 20 April 2021.
  6. ^ "Definition of CAMELOPARD". m-w.com. Encyclopædia Britannica: Merriam-Webster. Archived from the original on 25 April 2009. Retrieved 3 September 2014.
  7. ^ "Definition of camelopard". Dictionary of Medieval Terms and Phrases. Archived from the original on 4 September 2014. Retrieved 3 September 2014.
  8. ^
    S2CID 6522531
    .
  9. .
  10. ^ .
  11. ^ .
  12. ^
    S2CID 84406669. Archived from the original
    (PDF) on 23 August 2004.
  13. .
  14. .
  15. ^ .
  16. ^ from the original on 6 July 2022. Retrieved 1 August 2022.
  17. .
  18. ^ .
  19. ^
    JSTOR 3503830. Archived from the original
    (PDF) on 21 April 2017. Retrieved 25 October 2011.
  20. from the original on 3 April 2021. Retrieved 21 April 2021.
  21. ^ from the original on 22 September 2023. Retrieved 17 October 2020.
  22. ^ .
  23. ^ .
  24. ^ .
  25. ^ .
  26. ^ a b Linnaeus, C. (1758). Systema Naturæ.
  27. ^
    PMID 17434121
    .
  28. ^ a b c d e f g h i Seymour, R. (2001). Patterns of subspecies diversity in the giraffe, Giraffa camelopardalis (L. 1758): comparison of systematic methods and their implications for conservation policy (Ph.D. thesis).
  29. ^
    ISIS. 2010. Archived from the original
    on 6 July 2010. Retrieved 4 November 2010.
  30. ^ Swaison 1835. Camelopardalis antiquorum. Bagger el Homer, Kordofan, about 10° N, 28° E (as fixed by Harper, 1940)
  31. ^ "Exhibits". Al Ain Zoo. 25 February 2003. Archived from the original on 29 November 2011. Retrieved 21 November 2011.
  32. ^ "Nubian giraffe born in Al Ain zoo". UAE Interact. Archived from the original on 20 March 2012. Retrieved 21 December 2010.
  33. ^ . Retrieved 19 November 2021.
  34. ^ .
  35. ^ Fennessy, J.; Marais, A.; Tutchings, A. (2018). "Giraffa camelopardalis ssp. peralta". IUCN Red List of Threatened Species. 2018: e.T136913A51140803.
  36. from the original on 1 August 2020. Retrieved 16 September 2019.
  37. ^ .
  38. ^ "For the first time in decades, Angolan giraffes now populate a park in Angola". NPR. 2023. Archived 12 July 2023 at the Wayback Machine, Megan Lim, NPR, 11 July 2023
  39. ^
    PMID 25927851
    .
  40. ^ .
  41. .
  42. from the original on 22 September 2023. Retrieved 17 October 2020.
  43. ^ .
  44. ^ .
  45. .
  46. ^ "Giraffa Brisson 1762 (giraffe)". paleobiodb.org. Archived from the original on 5 December 2021. Retrieved 9 December 2021.
  47. ^ from the original on 22 September 2023. Retrieved 30 August 2021.
  48. ^ .
  49. ^ .
  50. ^ Langley, L. (2017). "Do zebras have stripes on their skin?". National Geographic. Archived from the original on 1 April 2019. Retrieved 2 June 2020.
  51. ^ .
  52. ^ .
  53. from the original on 14 December 2022.
  54. from the original on 22 September 2023. Retrieved 14 December 2022.
  55. ^ from the original on 20 November 2018. Retrieved 19 October 2011.
  56. ^ Fine Maron, Dina (12 September 2023). "Another rare spotless giraffe found—the first ever seen in the wild". National Geographic. Retrieved 6 March 2024.
  57. ^ Romo, Vanessa; Jones, Dustin (6 September 2023). "A rare spotless giraffe gets a name to match". NPR. Retrieved 6 March 2024.
  58. .
  59. ^ .
  60. .
  61. .
  62. .
  63. ^ .
  64. ^ (PDF) from the original on 25 March 2009.
  65. ^ (PDF) on 10 November 2011. Retrieved 21 November 2011.
  66. from the original on 2 June 2020. Retrieved 5 December 2019.
  67. S2CID 18821024. Archived from the original
    (PDF) on 10 November 2011. Retrieved 7 March 2012.
  68. ^ (PDF) on 16 May 2013. Retrieved 2 February 2012.
  69. .
  70. .
  71. .
  72. .
  73. .
  74. ^ Wood, C. (2014). "Groovy giraffes…distinct bone structures keep these animals upright". Society for Experimental Biology. Archived from the original on 25 November 2018. Retrieved 7 May 2014.
  75. (PDF) on 20 November 2018. Retrieved 25 April 2010.
  76. .
  77. ^ .
  78. ^ from the original on 4 December 2013. Retrieved 30 December 2010.
  79. .
  80. ^ (PDF) from the original on 29 October 2013.
  81. .
  82. .
  83. (PDF) from the original on 20 November 2018. Retrieved 27 November 2011.
  84. .
  85. (PDF) from the original on 20 November 2018. Retrieved 21 November 2011.
  86. (PDF) from the original on 22 July 2018.
  87. .
  88. .
  89. ^ Fennessy, J. (2004). Ecology of desert-dwelling giraffe Giraffa camelopardalis angolensis in northwestern Namibia (PhD thesis). University of Sydney. Archived from the original on 20 November 2018. Retrieved 30 January 2012.
  90. ^ .
  91. ^ from the original on 22 September 2023. Retrieved 22 August 2023.
  92. (PDF) on 6 November 2013.
  93. ^ .
  94. ^ .
  95. .
  96. ^ .
  97. ^ .
  98. S2CID 233600744. Archived 8 March 2022 at the Wayback Machine
  99. .
  100. .
  101. ^ .
  102. (PDF) from the original on 10 February 2020.
  103. ^ .
  104. .
  105. .
  106. .
  107. ^ from the original on 25 May 2021. Retrieved 10 February 2021.
  108. .
  109. .
  110. ^
  111. .
  112. .
  113. (PDF) from the original on 19 July 2018. Retrieved 12 June 2017.
  114. .
  115. .
  116. ^ .
  117. .
  118. .
  119. .
  120. from the original on 22 September 2023. Retrieved 22 August 2023.
  121. .
  122. .
  123. .
  124. .
  125. .
  126. ^ .
  127. from the original on 7 November 2011. Retrieved 6 November 2011.
  128. .
  129. S2CID 13488215. Archived from the original
    on 23 September 2015. Retrieved 16 November 2011.
  130. .
  131. (PDF) from the original on 10 September 2008.
  132. pps. 20–21.
  133. ^ Ian Cunnison (1958). "Giraffe hunting among the Humr tribe". Sudan Notes and Records. 39.
  134. ^ "Giraffe – The Facts: Current giraffe status?". Giraffe Conservation Foundation. Archived from the original on 19 March 2016. Retrieved 21 December 2010.
  135. ^ Matt McGrath (8 December 2016). "Giraffes facing 'silent extinction' as population plunges". BBC News. Archived from the original on 21 May 2019. Retrieved 8 December 2016.
  136. ^ "New bird species and giraffe under threat – IUCN Red List". 8 December 2016. Archived from the original on 5 March 2017. Retrieved 8 December 2016.
  137. .
  138. .
  139. ^ .
  140. from the original on 9 February 2023. Retrieved 30 June 2022.
  141. from the original on 26 October 2020. Retrieved 16 November 2020.
  142. .
  143. .
  144. from the original on 22 September 2023. Retrieved 13 July 2016.
  145. ^ "National Symbols: National Animal". tanzania.go.tz. Tanzania Government Portal. Archived from the original on 18 January 2015. Retrieved 14 January 2015.
  146. ^ "Chimpanzees among 33 breeds selected for special protection". BBC News. 28 October 2017. Archived from the original on 29 October 2017. Retrieved 30 October 2017.
  147. ^ "Good News for Giraffes at CITES CoP18 > Newsroom". newsroom.wcs.org. Archived from the original on 27 September 2020. Retrieved 16 November 2020.
  148. .
  149. from the original on 24 September 2020. Retrieved 16 November 2020.
  150. .

External links