This grouping encompasses current and former members of the suborder Suina, which is a group of omnivorous, non-ruminant, artiodactyl (i.e. even-toed ungulate) mammals.
Members of the family Suidae, or pig family, go by a variety of names, such as pigs, hogs, boars, and swine. Other wild pigs belonging to this family are warthogs and babirusa. All these are found in the Old World (Africa, Asia and Europe). The New World is home to its own family of pigs, the peccary (family Tayassuidae).
Historically, hippopotamuses were historically classified along with the above two groups due their morphological likeness. Nowadays, however, they are classified as a sister group to the cetaceans (whales and dolphins). We have, however, chosen to include hippos here.
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