The iconic plains zebra (Equus quagga) is the most abundant and conspicuous of all Africa’s diverse fauna. This species exhibits a large degree of diversity, and is currently separated into six subspecies based on variations in features such as coat patterning, the presence of a mane, extent of stripe coverage and body size. The plains zebra typically possesses relatively broad black stripes, which are vertical on the body, but become horizontal on the hindquarters. The presence of horizontal stripes on the legs and rump is, however, variable, with the extent of leg striping diminishing from the north to the south of the species' range. In some populations there may also be faint brown 'shadow' stripes between the main stripes. Various theories have been put forward to explain the function of zebra stripes, including dazzling predators and temperature regulation, but the most plausible theory appears to be that they serve a social function, stimulating group cohesion and grooming behaviour. Other methods of plains zebra communication include facial expressions, body movements, and sounds, such as a braying bark. An adaptable species, the plains zebra is capable of surviving in areas with coarse vegetation of little nutritional value, and is found at elevations up to 4,300 m. Although it has disappeared from many parts of its range, the plains zebra remains the most widespread and abundant equid on Earth. The plains zebra is often the first species to colonize unexploited areas of grassland, and is capable of traveling long distances to do so.