Zebras are social animals that spend time in herds. The most common species are plains zebras. They live in small family groups consisting of a male (stallion), several females, and their young. These units may combine with others to form awe-inspiring herds thousands of head strong, but family members will remain close within the herd.
Like horses, zebras sleep standing up, and only sleep when neighbours are around to warn them of predators. They communicate with each other with high pitched barks and whinnying. When a predator is spotted or sensed, a zebra will bark (or bray) loudly. A herd has many eyes alert to danger. If an animal is attacked, its family will come to its defense, circling the wounded zebra and attempting to drive off predators. When attacked by packs of hyenas, lions or wild dogs a zebra group will huddle together with the foals in the middle while the stallion tries to ward them off.