The average length of a giraffe's tongue is about 18 inches. Its color is black with some shades of purple. The back of it is usually pink. The prehensile tongue is used by the animals as a tool for getting food (leaves mostly). Male and female individuals prefer to feed on leaves separately. Thus, males tend to grasp leaves from the top of the tree, while females get leaves on the level of their height. Giraffes spend up to 20 hours eating. That is why the dark color of their tongue is a kind of protection of the bulk of the tongue from possible sunburns.