Giraffes consume bones, a behavior known as osteophagia, which involves seeking out and interacting with skeletal remains. This natural adaptation helps these large herbivores meet specific nutritional needs.
Giraffe’s Typical Diet
Giraffes are primarily herbivores, browsing on leaves, twigs, and fruits of trees and shrubs, particularly acacia species. Their impressive height and long tongues allow them to reach foliage inaccessible to other ground-based animals. A giraffe can consume up to 34 kilograms of plant material daily to sustain its large body.
Why Giraffes Seek Bones
Despite their extensive plant-based diet, giraffes sometimes face deficiencies in essential minerals. Their regular forage, especially during dry seasons, may not provide sufficient calcium and phosphorus. These minerals are important for maintaining bone density and supporting bodily functions. Bones are a concentrated source of these necessary nutrients, prompting giraffes to seek them out as a supplement.
Giraffes have a substantial skeletal structure, requiring calcium and phosphorus for maintenance and growth. While calcium can be obtained from leaves, phosphorus is often less readily available in their plant diet. This mineral deficiency drives osteophagia, as bones offer a readily accessible supply of these elements. This behavior is particularly noticeable during winter months when plant nutritional quality declines.
The Act of Bone Eating
When engaging in osteophagia, giraffes interact with dry, sun-bleached skeletal remains. They do not swallow bones whole; instead, they use their powerful tongues and mouths to lick, gnaw, and scrape the surface. This process allows them to extract small quantities of minerals from the bone’s exterior.
Observations show giraffes often adopt a specific posture while chewing bones, pulling their ears back and lifting their chins. This helps prevent bone fragments from falling out, maximizing mineral intake. While bones can soften when exposed to saliva, studies suggest the primary benefit comes from surface extraction rather than direct digestion.
Implications for Wild Giraffes
Osteophagia is a natural behavior that supports the health and survival of wild giraffe populations. By supplementing their diet with minerals from bones, giraffes receive necessary nutrients for their large bodies and rapid growth. This behavior is not unique to giraffes; many other herbivores also exhibit osteophagia when facing mineral deficiencies. It highlights how animals adapt their feeding strategies to cope with environmental conditions and nutritional challenges.