Giraffe

• 1. Introduction

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  A giraffe can land a blow with its head powerful enough to break another giraffe's jaw, snap its neck, or kill it outright. The weapon is the neck itself, swung in arcs during contests that can last more than half an hour. This is the tallest living land animal, standing between 4.3 and 5.7 metres, and the largest ruminant on Earth. Its nearest living relative is a shy forest dweller called the okapi. The two are the only surviving members of the family Giraffidae. For an animal so familiar in paintings, books, and cartoons, the giraffe holds a surprising number of unsettled questions. How many species of giraffe actually exist? Why did the neck grow so long, and what does that length cost the animal that carries it? How does a heart pump blood up to a brain held metres above the ground without the animal fainting every time it bends to drink? And how did a creature that once numbered 155,000 in the wild fall to roughly 97,500 in a single generation?

• 2. Counting The Species

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  Carl Linnaeus classified the living giraffe as a single species in 1758, giving it the binomial name Cervus camelopardalis. A few years later, in 1762, Mathurin Jacques Brisson coined the generic name Giraffa that the animal still carries. For most of the next two centuries the giraffe was treated as one species, Giraffa camelopardalis, divided into nine subspecies. That settled picture has fractured. A 2007 study of mitochondrial DNA suggested at least six lineages could count as species. A 2011 study of giraffe morphology described eight living species. A 2016 study proposed four, arguing these groups had not exchanged genetic information for one to two million years. A 2020 study warned that some statistical methods over-split giraffes, delimiting geographic structure rather than true species, and found that anywhere from two to six species could be defended depending on the method. The three-species hypothesis, recognising G. camelopardalis, G. giraffa, and G. tippelskirchi, draws strong support from phylogenetic analysis. By 2021, whole genome sequencing pointed to four distinct species and seven subspecies, a conclusion backed by a 2024 study of cranial morphology. In 2025 the International Union for Conservation of Nature accepted four species and seven subspecies. The fur coat is what tells these groups apart. The West African giraffe of southwestern Niger wears red lobe-shaped blotches and is the most endangered, with 400 individuals left in the wild. The reticulated giraffe of northeastern Kenya, southern Ethiopia, and Somalia carries sharp-edged reddish-brown polygons, and a 2024 study found it is the product of hybridisation between northern and southern lineages.

• 3. A Long Walk Out Of Asia

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  Canthumeryx, an antelope-like animal dated to roughly 17 to 15 million years ago, left its deposits in Libya and stands near the root of the giraffe lineage. Neck elongation began early, and the order of it can be read in the fossils: vertebrae near the skull lengthened first, then those further down the spine. Giraffokeryx appeared 15 to 12 million years ago on the Indian subcontinent, resembling an okapi or a small giraffe, with a longer neck and similar ossicones. Samotherium, which lived from around 14 million years ago, became a key transitional fossil, since its cervical vertebrae sat halfway between the okapi's and the modern giraffe's in both length and structure. Bohlinia, first appearing in southeastern Europe between 9 and 7 million years ago, was likely a direct ancestor of Giraffa, already carrying the long neck, long legs, and characteristic ossicones. Bohlinia colonised China and northern India and gave rise to Giraffa, which then reached Africa. Climate changes wiped out the Asian giraffes while the African ones survived and radiated into new forms. The shift from dense forests to open country, beginning 8 million years ago, is thought to be the main engine of giraffe evolution. Tropical plants gave way to arid C4 plants, and dry savannah spread across eastern and northern Africa and western India. Some researchers suspect the new diet, including acacia, exposed giraffe ancestors to toxins that raised mutation rates and quickened evolution. The divergence of giraffe and okapi lineages dates to around 11.5 million years ago, and only 19.4 percent of the proteins in their genes are identical.

• 4. The Riddle Of The Neck

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  The giraffe's neck can reach 2.4 metres, yet it holds the same seven cervical vertebrae as almost every other mammal. The length comes from stretching those bones, not adding more: each cervical vertebra runs over 28 centimetres long. Together they make up 52 to 54 percent of the vertebral column, against the 27 to 33 percent typical of similar large ungulates, including the okapi. Most of this stretching happens after birth, perhaps because a mother could not deliver a calf built to adult proportions. Charles Darwin offered the first explanation, the competing browsers hypothesis. It holds that pressure from smaller browsers like kudu, steenbok, and impala pushed the neck longer, letting giraffes reach food rivals could not. The advantage is real: giraffes feed up to 4.5 metres high, while even a large kudu reaches only about 2 metres. The story is not clean, though. A 2010 study found that giraffes with longer necks suffered higher death rates during droughts, because a longer neck demands more nutrients when food runs short. A rival idea, the sexual selection hypothesis, casts the long neck as a weapon and a sexual ornament, sharpened by necking contests for access to females. Supporters note males have thicker, heavier necks and rely on no other form of combat. Yet a 2024 study complicated even this, finding that while males have thicker necks, females have proportionally longer ones, likely because they must find more food to feed themselves and their young. One anatomical detail keeps the debate alive. The joint between neck and chest sits between the first and second thoracic vertebrae rather than the usual position, prompting the suggestion that the giraffe has quietly added an eighth cervical vertebra.

• 5. Built To Stand Tall

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  A giraffe's heart weighs about 25 pounds, measures roughly 2 feet, and must generate around double the blood pressure a human needs to push blood up to the brain. The heart wall can be as thick as 7.5 centimetres, and the animal runs a high heart rate for its size at 150 beats per minute. When a giraffe drops its head to drink, a network of vessels called a rete mirabile in the upper neck blunts the rush of blood toward the brain. When the head lifts again, vessels constrict and force blood upward so the animal does not faint. The jugular veins carry valves, most commonly seven, to stop blood draining back into the head. In the lower legs the problem reverses: pressure from the weight of fluid is so great that the skin must be thick and tight to keep blood from pooling. The animal's proportions reach absurd extremes elsewhere. The left recurrent laryngeal nerve runs over 30 centimetres longer than the right and stretches more than 2 metres, the longest such nerve in any living animal. A single nerve cell along this path, looping down the neck and back up to the larynx, spans nearly 5 metres in the largest giraffes. The tongue runs about 45 centimetres, coloured black perhaps to guard against sunburn, and the intestines of an adult exceed 70 metres. Scientists have studied giraffe skin as a model for astronaut and fighter pilot suits, since both professions risk blacking out when blood rushes to the legs.

• 6. Herds, Calves And Combat

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  A giraffe group can hold anywhere from one animal to 66. For decades these gatherings were described as open and ever-changing, but newer research finds lasting cliques built on kinship and sex within a fission-fusion society. In Tanzania, Masai giraffes sort into subpopulations of 60 to 90 adult females with overlapping ranges, linked by roaming males into super communities of around 300 animals. Early biologists thought giraffes were mute, unable to push enough air to vibrate their vocal folds. They were wrong. Giraffes snort, sneeze, cough, snore, hiss, moan, grunt, and growl, and during the night they appear to hum to one another, possibly using Helmholtz resonance to produce infrasound. Reproduction is broadly polygamous, with a few older males mating with fertile females. Females cycle into oestrus roughly every 15 days, and males test fertility by tasting urine in the flehmen response. Gestation lasts 400 to 460 days, and the mother gives birth standing, so the calf drops to the ground and severs its own umbilical cord. A newborn stands 1.7 to 2 metres tall and can run within hours, yet spends its first one to three weeks hiding. Mothers gather in nursery herds and sometimes leave their young in a calving pool watched by one female while the others forage. Combat is the other side of giraffe society. Males that win necking bouts gain greater reproductive success, swinging their skulls so the ossicones land as blows. After a duel, two males commonly caress and court each other; in one study, up to 94 percent of observed mounting took place between males.

• 7. Living With Humans

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  Julius Caesar brought the first giraffe to Rome in 46 BC, and the Romans displayed it among their collected animals. Long before that, the Kiffians carved a life-size rock engraving of two giraffes some 8,000 years ago, a work called the world's largest rock art petroglyph. The animal threaded through belief as well as art. In the ancient Kushite societies of Nubia, now northern Sudan, giraffes may have figured in popular and women's religion and in ideas about the sun, while the Tugen people of Kenya used the giraffe to depict their god Mda. The Egyptians gave it its own hieroglyph and were among the first to keep giraffes in captivity, shipping them around the Mediterranean. Captive giraffes won celebrity. In 1414, a giraffe from Malindi was carried to China by the explorer Zheng He and placed in a Ming dynasty zoo, where people linked it to the mythical Qilin. The Medici giraffe, presented to Lorenzo de' Medici in 1486, caused a stir on arrival in Florence. In the early 19th century a giraffe named Zarafa travelled from Egypt to Paris as a gift for Charles X of France and spawned a wave of memorabilia called giraffanalia. Modern culture kept the fascination alive. Salvador Dali painted giraffes with burning manes as masculine cosmic monsters, and the animal appears in children's books like Giraffes Can't Dance and Roald Dahl's The Giraffe and the Pelly and Me. Sophie the Giraffe has sold as a teether since 1961. Among the Humr people of Kordofan, a drink called Umm Nyolokh, made from giraffe liver and bone marrow, is said to cause hallucinations of giraffes believed to be their ghosts.

• 8. A Shrinking Range

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  In 1985, an estimated 155,000 giraffes lived in the wild. By 1999 the figure had slipped past 140,000, and estimates for 2016 put the population at roughly 97,500. That year the IUCN assessed the giraffe as Vulnerable. The decline is uneven across the new species and subspecies: the Masai and reticulated are endangered, the Rothschild near threatened, and the Nubian critically endangered. Habitat loss and direct killing for bushmeat markets are the main drivers. Giraffes have already vanished from much of their historic range, including Eritrea, Guinea, Mauritania, and Senegal, and may be gone from Angola, Mali, and Nigeria, though they have been introduced to Rwanda and Eswatini. In the Sahel, the hunt for firewood and grazing room has stripped away forest. Giraffes normally coexist with livestock by feeding above them, but in 2017 severe droughts in northern Kenya sharpened conflict over land and led herders to kill wildlife, hitting giraffe populations hard. Protection has grown alongside the threat. The giraffe is the national animal of Tanzania, where unauthorised killing can bring imprisonment. The UN-backed Convention of Migratory Species selected giraffes for protection in 2017, and in 2019 they were listed under Appendix II of CITES, regulating international trade in their parts. Counting them remains its own challenge. Aerial survey is the most common method across the vast roadless tracts of Africa, but it is known to undercount giraffes, which is why ground-based methods are paired with it to sharpen the estimates that will measure whether the decline can be reversed.