Cetacea

Cetacea (/sᵻˈteɪʃə/), (from Latin cetus "whale" and Greek ketos "huge-fish") are a widely distributed and diverse clade of carnivorous, finned, aquatic marine mammals. They comprise the extant parvorders Odontoceti (toothed whales including dolphins and porpoises), Mysticeti (the baleen whales), and Archaeoceti (the ancestors of modern whales, and is now extinct). There are around 89 species of cetaceans, and more than 70 belonging to Odontoceti. While cetaceans were historically thought to have descended from mesonychids, molecular evidence supports them as a relative of Artiodactyls (even-toed ungulates). Cetaceans belong to the order Cetartiodactyla (formed by combining Cetacea + Artiodactyla) and their closest living relatives are hippopotamuses and other hoofed mammals (camels, pigs, and ruminants), having diverged about 50 million years ago.