Pygmy hippopotamus the pygmy hippopotamus, are considered dwarf hippopotamuses, rather than pygmies. They are likely descended from a full-sized species of European hippopotamus, and reached their small size through the evolutionary process of insular dwarfism which is common on islands; the ancestors of pygmy hippopotami were also small and thus there was never a dwarfing process. There were also several species of pygmy hippo on the island of Madagascar (see Malagasy hippopotamus). Pygmy hippos share the same general form as a hippopotamus. They have a graviportal skeleton, with four stubby legs and four toes on each foot, supporting a portly frame. The
Mountain pygmy possum is hairless. On the underside of the female's body is a pouch containing four teats. This possum is the only extant species in the genus "Burramys". It is also the only Australian mammal restricted to alpine habitat. The mountain pygmy possum was first discovered in the fossil record in 1895 when a portion of the jaw and skull bones were found in the Wombeyan Caves in central New South Wales. At the time, the species was believed to be extinct. It was not until 1966 that a living individual was found at a ski resort at Mount Hotham in Victoria.