What Do Giraffes Eat? Acacia Leaves and a Long Tongue

What plants do giraffes eat?

Giraffes are browsers, animals that feed on woody plants rather than grass. Their favorite foods are the many species of acacia trees, now often split into the genera Vachellia and Senegalia, along with Commiphora, Combretum and Terminalia trees. These leaves are rich in protein and calcium, which giraffes need to grow and to build their huge skeletons.

They also eat flowers, fruit, seed pods, buds and young twigs, and switch to evergreen trees and shrubs in the dry season. In any one area a giraffe may feed on dozens of different plant species. Grass is eaten only rarely. Giraffes are ruminants with a four-chambered stomach, like cows, and they chew the cud: you can see a ball of food travel up the long neck to be chewed again.

How much does a giraffe eat?

An adult giraffe eats about 34 kg (75 lb) of plant matter a day. That sounds like a lot, but it is less than you might expect for an animal weighing up to 1,930 kg (4,250 lb). The leaves giraffes choose are nutritious, and their digestive system is efficient at extracting energy from them.

Feeding peaks in the early morning and late afternoon. During the hot middle of the day giraffes mostly stand in the shade and chew the cud, and rumination continues through much of the night, often while lying down. Male and female giraffes also feed differently: males often stretch to the highest branches, while females more often bend their necks to feed at body height or lower, which may reduce competition between them.

How does a giraffe’s tongue work?

The giraffe’s tongue is about 45–50 cm (18–20 in) long, muscular and prehensile, so it can curl around a branch like a hand. The giraffe wraps it around a twig, pulls it into the mouth and strips the leaves off by drawing its head back. The front part of the tongue is dark blue-black, which may help protect it from sunburn during long hours of feeding in strong sunlight.

The upper lip is flexible and covered in hair, and the giraffe has no upper front teeth, only a hard pad. Together, the lips, tongue and pad let it pick leaves delicately from between sharp spines.

How do giraffes cope with thorns?

Acacia trees defend themselves with long, sharp thorns, yet giraffes eat them every day. Their tough lips, grasping tongue and thick, sticky saliva help them handle prickly branches, and they often pick leaves from between the thorns rather than biting through them. Thorns do slow them down, though, and giraffes feeding on heavily armed trees take fewer leaves per bite.

Some acacias have extra defenses. The whistling thorn acacia of East Africa houses colonies of ants that swarm out and bite browsing animals, and studies in Kenya showed that these ants reduce how much giraffes and elephants eat from those trees. Many acacias also produce bitter tannins, which encourage giraffes to move on after a few mouthfuls.

Why do giraffes chew bones?

Giraffes are sometimes seen chewing old bones they find on the ground. This behavior, called osteophagia, is thought to help them get extra calcium and phosphorus, which they need to grow and maintain their large skeletons, especially in areas with poor soils. It does not mean giraffes eat meat; they are strictly plant eaters.

How do giraffes drink?

Giraffes get much of their water from fresh leaves and can go several days without drinking. When they do drink, they must spread their front legs wide or bend their knees and lower their heads to the water. In this awkward pose they are vulnerable, so giraffes at water holes are often seen taking turns, with some drinking while others stay upright and watchful.

Special valves in the neck veins and a network of blood vessels near the brain stop blood from rushing to the head while the giraffe drinks, and help prevent dizziness when it lifts its head again.

How does a giraffe’s diet affect the savanna?

Because giraffes browse so heavily, they shape the trees they feed on. Constant nibbling can keep young trees short for years and gives tall acacias a typical flat-topped or “waisted” shape, where the lower canopy has been trimmed to the giraffes’ reach. Giraffes also spread seeds in their droppings, and they may even help pollinate some acacias by carrying pollen on their faces as they feed on flowers.

Reaching high leaves is also one of the leading explanations for the giraffe’s famous build; see Why do giraffes have long necks? and How tall is a giraffe? For more on the animal itself, visit our giraffe profile, or see how other animals compare in herbivores, carnivores and omnivores.