The distinctive stripes of the zebra run diagonally and lengthways on the rump and continue on to the belly. On the rump there are usually chestnut or yellowish shadow stripes in the middle. These stripes make it harder for predators to identify a single animal from the running herd. They may also dissuade insects that reconize only large areas of single-colored fur. Zebras are social animals that spend time in herds. They graze together, primarily on grass, and even groom one another.