Zebras belong to the same scientific family as horses. Zebras’ coats are covered in black and white stripes, and each zebra has its own, unique pattern that is different from any other zebra. Zebras are social animals that live in large herds. They are herbivores that tend to graze on grasses. They are often found in the same habitat as wildebeest, and in the Serengeti and Masai Mara, many do the great migration alongside other ungulates. Zebras are diurnal animals and are most active during daylight hours. There are presently three species of zebra in existence: plains zebra—most populous of the three, mountain zebras—found mainly in southwestern Africa and Grévy's zebra—the largest of the three species and also the most endangered. It is mainly found in Kenya and Ethiopia. Zebras possess excellent hearing and eyesight, which make them valuable additions to the great wildebeest migration. Wildebeest do not possess good eyesight and young wildebeest will often watch zebras’ reaction to determine their own safety. Wildebeest do have a good sense of hearing and smell. The gestation period for females is 12 to 13 months, with one young being the average number born.