With their stilt-like legs, incredibly long necks and dexterous, elongated tongues, giraffes (Giraffa camelopardalis) are able to feed on foliage that's out of reach to other herbivores. Despite this latitude in food choices, giraffes overwhelmingly prefer browsing on the shoots and leaves of trees and shrubs, particularly the very thorny Acacia species.
Unlike many of Africa’s large mammalian herbivores, which alternate between browsing and grazing, giraffes are almost exclusively browsers – feeding primarily on leaves and the protein-rich shoots of trees and shrubs. They will also eat herbs and vines, as well as fruits and flowers when available. Giraffes have occasionally been observed grazing on grasses in nutrient-poor environments, although the position required to reach the ground makes them more susceptible to predators. In most areas, trees and shrubs in the Acacia species – a cousin of mimosas – make up the bulk of their diet. Giraffes use their long, prehensile tongues to navigate through the trees’ thorny branches to find tender shoots and leaves. Thickened papillae along the tongue’s surface further protect the giraffe from thorns. With their unusual physique, giraffes can comfortably feed between 1.6 and 15 feet off the ground. The next tallest browser – the kudu – can only reach 6.5 feet.
Give the Giraffe a Bone
With respect to feeding ecology, male and female giraffes are not created equal. The males, 20 percent taller than the females, can feed at higher levels. Breeding females tend to consume more nutritionally rich foods, whereas bulls eat foods higher in fiber and lignin. In a 2003 study on the foraging preferences of giraffes in Niger, Lauren E. Caister and her colleagues of the State University of New York at Syracuse found that nursing cows avoided leaves high in tannin, even when it meant giving up higher-quality forage. To support the growth of their unique skeletons, giraffes require two to three times more calcium and phosphorous than other similar-sized mammals. Most of their calcium requirements are met through diet, but sources of sufficient phosphorous remain a mystery. In a 2008 study, University of Pretoria's I. P. Bredin and his colleagues hypothesized that giraffes may acquire phosphorous from eating bones, a behavior known as osteophagia, which is frequently observed in giraffes, particularly in the winter months when the nutrient quality of foliage falls.
- Journal of Ecology: Consequences of Herbivory by Native Ungulates for the Reproduction of a Savanna Tree
- African Journal of Ecology: Grazing Behaviour of the Giraffe in Hwange National Park, Zimbabwe
- Giraffe Reflections; Dale Peterson
- Giraffe: Biology, Behavior and Conservation; Anne Innis Dagg
- Ethology: Sex Differences in Giraffe Feeding Ecology: Energetic and Social Constraints
- African Journal of Ecology: Female Tannin Avoidance: A Possible Explanation for Habitat and Dietary Segregation of Giraffes (Giraffa Camelopardalis Peralta) in Niger
- Onderstepoort Journal of Veterinary Research: Can Osteophagia Provide Giraffes With Phosphorus and Calcium?
- Photo Credit Chestertonjp/iStock/Getty Images
How Long Does a Giraffe Live?
Giraffes are tall, powerful creatures. They can eat the leaves from the tops of high trees with ease, they are adept at...
Physically and behaviorally well-suited to their environment, giraffes are an extraordinary example of adaptation in the animal world. Inhabiting grasslands and open...
A Giraffe's Natural Habitat
Giraffes are native to many parts of Africa as they prefer habitats with lots of open space, rather than wooded forests. Many...
Ecosystems in the African Savanna
A savanna is an grassland ecosystem with a thin distribution of trees. Over a third of Africa, approximately 5 million square miles,...
What Animals Do Lions in a Savanna Eat?
Savannas are found in a band on either side of the equator. They are made up of grassland, with a few trees...
What Do Zebras Eat?
Zebras eat very coarse grass, as they have bacterial enzymes in their stomachs that help break down an abundance of plant material....
What Do Giraffes Eat?
Giraffes are herbivores, which means they eat plant material like leaves high in the trees, acacia and leaves from bushes. Learn about...
How Long Does a Giraffe Live?
Giraffes can live up to 26 years old in the wild, but they can live much longer in captivity where disease and...