Giraffes

Overview

Because of their long necks and legs, giraffes are the tallest animals in the world. A few dwarf giraffes have been reported as well.

Patch coloration and shape can vary within their extensive habitat range. Patch shape is inherited through the mother. Some giraffes have no patches: the first spotless giraffe was observed in the wild in 2023. Rarely, giraffes are born completely white, with dark eyes.

Females have shorter, inward-curving horns than the males do. In both sexes, a long mane of stiff, brushlike hairs extends from the back of the head to the shoulders.

Giraffes exhibit a unique, fluid gait. When walking, the fore and hind legs on the same side appear to move almost in unison. Swift and fleeting, giraffes can gallop up to thirty-three miles per hour. When they gallop, the front legs move together and their hind legs move forward and outward, enveloping the forelegs in a unique rhythmic pattern. Long and graceful, their sleek necks swing back and forth rhythmically with their legs. The neck has remarkable range of motion. A system of blood vessels and valves in the neck protects the brain and reduces blood pressure when the animal lowers its head.

Quick Facts

• Kingdom: Animalia
• Subkingdom: Bilateria
• Phylum: Chordata
• Subphylum: Vertebrata
• Class: Mammalia
• Order: Artiodactyla
• Family: Giraffidae
• Genus and species: Giraffa camelopardalis, with eleven subspecies
• Geographical location: Africa, south of the Sahara
• Habitat: Dry, open savanna biomes, covered with bush and acacia trees
• Gestational period: About 450 days
• Life span: Up to twenty-five years in the wild; up to twenty-eight years in captivity
• Special anatomy: A long neck with seven vertebrae (characteristic of all mammals); typical adult height of between fifteen and eighteen feet; patches of various sizes and shapes; sloping back ending in a long, tufted tail; a pair of horns on top of the head

Diet

Although some may feed at night, giraffes are classified as herbivorous diurnal eaters. They are browsers, and competition for food is greatly reduced because of the height at which they feed. The male feeds at greater heights, with his head stretched upward, whereas the female feeds at lower heights, often bending her head and neck to reach the leaves.

Giraffes feed mainly on the highly nutritious leaves, fruit, and flowers of acacia trees. Their long, dexterous tongues strip leaves from the acacia twigs. Giraffes often consume soil and bones to balance the phosphorus and calcium in their blood.

When feeding on sprouted vegetation and when drinking water, giraffes splay their front legs and bend their knees. In such a position, they are vulnerable to predators, especially lions. Giraffes can go without water for days.

Protection, Defense, and Communication

Generally docile creatures, giraffes may kill other animals with a kick of a fore or hind hoof. Their heads, used like a knight’s mace, land formidable blows on the body or legs of opponents. The effective use of their heads as weapons is enhanced by the physical structure of horns and knobs. The skull bone is solid and thick, so that its force can result in a fatal blow. The giraffe’s own head is protected by extensive sinuses, which absorb shock. Male giraffes tend to fight by "necking" and appear to prefer fair fights, selecting opponents of similar size and age.

Giraffes snort, grunt, bleat, bellow, and moo to communicate. They hum to one another at night. Because of their height, giraffes’ sense of smell is not as keen as other animals. However, their sensitivity to sound and their visual acuity more than compensate for their underdeveloped sense of smell.

Reproduction and Birth

Mixed herds of variable numbers have been recorded in the field. Old males are often solitary.

Both same-sex and opposite-sex sexual behaviors have been observed among giraffes in the wild. About a day before mating with a male, the female becomes sexually attractive. At the onset of mating, the male licks the female’s genitals and catches her urine on his tongue. Chemical signals in her urine are detected by flehmen as the male’s Jacobson’s organ becomes activated. The male remains with the female in heat unless he is displaced by a higher-ranking challenger.

The female gives birth in cover, with her back legs bent to reduce the height from which the calf falls. Initially, the mother is alone with her calf, but later she may form a nursery group assisted by other females. The calf stands within five minutes of birth and suckles within the hour. The calf becomes independent of the mother around the sixteenth month. Play behavior, called nose-to-nose sniffing, between the young cements social bonds between them.

Environment

The giraffe's natural habitat, the savanna, is experiencing increasing trouble. Illegal hunting, disease, and habitat loss have contributed to declining numbers of savanna animals. Giraffes have also suffered loss in numbers. The masai giraffe has decreased to 35,000 and was labeled “endangered” in 2015. A 2016 study suggested that giraffes should be classified into four species instead of one. However, some giraffe population counts would then fall even lower and require even stricter conservation measures to protect them.

Scientists have attempted to relocate some giraffe populations in an effort to conserve them. Smaller electronic devices have also been deployed to help track giraffe movements. Giraffes were also added to the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) treaty to monitor the global trade in giraffe parts in the hope of reducing poaching.

Principal Terms

browser: feeds on shoots and leaves

diurnal: active during daylight hours

flehmen: behavior involving curling and wrinkling of lips and nostrils, with the activation of the Jacobson’s organ

hierarchy: a social structure in which animals are dominated by those higher on the linear ladder

Jacobson’s organ: a sense organ between the roof of the mouth and nasal passages, which detects chemical signals associated with reproduction

Bibliography

Apps, Peter. Creatures of Habit: Understanding African Animal Behavior. Struik, 2000.

Benyus, Janine M. The Secret Language and Remarkable Behavior of Animals. Black Dog & Leventhal, 1998.

Eschner, Kat. “There Are Four Giraffe Species—Not Just One.” Smithsonian Magazine, 12 Sept. 2016, www.smithsonianmag.com/smart-news/there-are-four-giraffe-species-not-just-one-180960411/. Accessed 1 Mar. 2024.

Gibbens, Sarah. “Why These Giraffes Are Completely White.” National Geographic, 14 Sept. 2017, www.nationalgeographic.com/animals/article/white-giraffes-kenya-video-spd. Accessed 1 Mar. 2024.

Main, Douglas. “Giraffe Populations Are Rising, Giving New Hope to Scientists.” National Geographic, 12 Jan. 2022, www.nationalgeographic.com/animals/article/giraffe-populations-rising-giving-hope. Accessed 1 Mar. 2024.

Maron, Dina Fine. “Another Rare Spotless Giraffe Found—the First Ever Seen in the Wild.” National Geographic, 12 Sept. 2023, www.nationalgeographic.com/animals/article/spotless-giraffe-found-in-the-wild-for-the-first-time?loggedin=true&rnd=1709307882426. Accessed 1 Mar. 2024.‌

Okoth, Dann. “Separated by Cliffs, the Masai Giraffe Is More Endangered than Previously Thought.” Nature Africa, 3 July 2023, https://doi.org/10.1038/d44148-023-00168-2. Accessed 1 Mar. 2024.

Vaughan, Terry A., et al. Mammalogy. 6th ed., Jones & Bartlett Learning, 2015.