Donkey the environment. They may compete with livestock and native animals for resources, spread weeds and diseases, foul or damage watering holes and cause erosion. Few species of ass exist in the wild. The African wild ass, "Equus africanus", has two subspecies, the Somali wild ass, "Equus africanus somaliensis", and the Nubian wild ass, "Equus africanus africanus", the principal ancestor of the domestic donkey. Both are critically endangered. Extinct species include the European ass, "Equus hydruntinus", which became extinct during the Neolithic, and the North African wild ass, "Equus africanus atlanticus", which became extinct in Roman times. There are five subspecies
Equus (genus) each other both visually and vocally. Human activities have threatened wild equine populations. The word "equus" is Latin for "horse", and is cognate with the Greek ἵππος ("hippos"), "horse", and Mycenaean Greek "i-qo" /ikkʷos/, the earliest attested variant of the Greek word, written in Linear B syllabic script.; compare the alternative development of the Proto-Greek labiovelar in Ionic ἴκκος ("ikkos"). The genus "Equus" was first described by Carl Linnaeus in 1758. It is the only recognized extant genus in the family Equidae. The first equids were small, dog-sized mammals (e.g. "Eohippus") adapted for browsing on shrubs during the Eocene, around