Equinae

Equinae is a subfamily of the family Equidae, known from the Hemingfordian stage of the Early Miocene (16 million years ago) onwards. They originated in North America, before dispersing to every continent except Australia and Antarctica. They are thought to be a monophyletic grouping. Members of the subfamily are referred to as equines; the only extant equines are the horses, asses and zebras of the genus Equus, with two other genera Haringtonhippus and Hippidion becoming extinct at the beginning of the Holocene, around 11–12,000 years ago. The subfamily contains three tribes, the extant Equini as well as the extinct Hipparionini and Protohippini. Members of the family ancestrally had three toes, while members of the tribe Equini from the Middle Miocene onwards developed monodactyl feet. They belong to the order Perissodactyla, meaning they are odd-toed animals.