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
Spined pygmy shark and insular slopes. It may also be found over outer shelves, but avoids central ocean basins. The range of this species does not overlap that of the pygmy shark, which has a similar ecology, and is also largely separate from that of the cookiecutter shark. One of the world's smallest sharks, the spined pygmy shark attains a maximum recorded length of for males and for females. This species has an elongated, spindle-shaped body with a long, bulbous, moderately pointed snout. The eyes are large, with the upper rim of the orbit almost straight. Each nostril is preceded by a short