The origins and evolution of equines, in particular zebras, are described. General descriptions of the habitats, diet, behaviors, predators, and pathogens of zebras are followed by accounts of mountain zebras (Equus zebra), plains zebras (Equus quagga), and Grévy's zebras (Equus grévyi). The morphology, taxonomy and behavior of these species are described. Grévy's zebras occur in Ethiopia and Kenya. Mountain zebras occur in South Africa and Namibia and exist as two subspecies: Cape mountain zebras (Equus zebra zebra) and Hartmann’s mountain zebras (Equus zebra hartmannae). Plains zebras vary in size and degree of striping, with both these characteristics forming a cline (gradient) over their range which extends from Ethiopia to South Africa. Six subspecies of plains zebras are recognized, including quaggas, Equus quagga quagga. The |Xam distinguished between quaggas and other zebras, but some other historical sources are unclear, which confuses the historical record. Data from the International Union for the Conservation of Nature (IUCN) and other sources are used to discuss the size of current populations and the conservation challenges faced by zebras.