A giraffe will eat between 30 and 40kg of food in one day. They are browsers taking preference to the Acacia trees. They have very long tongues (46cm), which they use to strip leaves off between all the thorns on the Acacias. If a thorn is taken in they simply spit it out. An amazing adaptation that giraffe have is that they don’t have any blood vessels in their gums, so they won’t bleed when pierced by a thorn. Their tongues get very rough and damaged by thorns over a period of time, so they are capable of shedding the outer layers of the tongue, leaving it soft and smooth once again.
The collective name for giraffe is a “journey of giraffe.” because they will not stay in the same area for too long feeding off the same trees. If a giraffe feeds on the same Acacia tree for too long a period, the tree then starts to defend itself by increasing the levels of tannin in its leaves. The increase of tannin makes the leaves taste very bitter and dry, forcing the giraffe to move on. The acacia at the same time releases chemicals into the air, which is carried by the wind to other Acacias as a signal to raise their tannin levels. With the whole area being tannin infested the giraffe then moves off to a totally different area, often feeding upwind to feed off trees that have lower tannin levels.
Giraffe being such tall animals makes it very difficult for them to drink. They are very wary of predators when approaching water, often stopping every few steps to scan their surroundings for any sign of danger. Once at the waters’ edge, they move their front legs apart and bend them to lower their bodies, then start drinking. In this position they are very vulnerable to lions as it is difficult for them to start running quickly when their legs are so far apart. When the giraffe lowers its head to drink, it gets no circulation of blood to the brain. Circulation is stopped by closing valves at the point where the main arteries’ enter the skull. These valves re-open when the animals head is lifted up again. This helps the giraffe by preventing a rush of blood into the brain when it lowers its head and a rush of blood out of its brain when the head is lifted, thus preventing it from passing out.
Giraffe very seldom sleep, and when they do they lie down on the belly, with the head resting against a large tree or termite mound. Sometimes they will rest their head on the lower part of the back when sleeping. The head is kept above ground level to ensure the circulation of blood to the brain is not cut off.
