Giraffes, the world’s tallest mammals, possess a unique feeding strategy that allows them to thrive in their diverse African habitats. Their height, which can reach up to 18 feet, gives them unique access to food sources unavailable to most other herbivores. This browsing behavior is central to their survival and shapes their distinctive physical characteristics.
Primary Plant-Based Diet
Giraffes are herbivores, and their diet primarily includes leaves, twigs, and buds from trees and shrubs. As browsers, they prefer foliage from woody plants rather than grazing on grass. Acacia trees are a staple food source in many African regions, providing essential nutrients for giraffe growth and maintenance.
Giraffes also consume leaves and shoots from mimosa and wild apricot trees. Their diet also includes herbs, climbers, vines, flowers, and fruits, depending on seasonal availability. To sustain their large bodies, giraffes consume up to 75 pounds (34 kilograms) of plant matter daily, often spending up to 18 hours foraging for food.
Unique Feeding Adaptations
Giraffes possess several physical adaptations that enable them to efficiently consume their diet, particularly thorny vegetation. Their long necks allow them to reach foliage as high as 20 feet off the ground. Complementing their height is a long, prehensile tongue, which can extend up to 18-20 inches (45-50 centimeters), allowing them to grasp branches and strip leaves with precision.
The giraffe’s tongue is often dark purple, blue, or black towards the front, with a pinkish base. This dark pigmentation is thought to protect the tongue from sunburn during prolonged sun exposure while feeding. Both their lips and the inside of their mouths are covered in tough, horny papillae and thick, sticky saliva, providing protection against sharp thorns. Their narrow muzzle and flexible upper lip further assist in selecting individual leaves without injury.
Water and Supplemental Intake
Giraffes primarily obtain water from the moisture in the leaves and vegetation they eat. This adaptation allows them to go for extended periods without drinking directly from a water source. The water content in their browse, combined with water produced through metabolism, meets their daily requirements.
When giraffes do drink water, they must splay their front legs or kneel to lower their heads to the ground, making them vulnerable to predators. They can drink a large amount, up to 10 gallons (38 liters) per day if water is available. Additionally, giraffes may occasionally chew on bones, a behavior called osteophagia. This provides supplementary calcium and phosphorus, minerals often lacking in their plant-based diet, especially during dry seasons. They chew bones to extract nutrients, but do not swallow them.