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 an underground tunnel was constructed which provided male pygmy possums with an alternative migratory route. Climate change is another serious threat to the mountain pygmy possum. "Burramys parvus" is the only Australian mammal which is completely restricted to the alpine regions. The species is well adapted to the seasonal availability of Bogong moths and other food resources. Although data from New South Wales and Victoria are still pending, preliminary models suggest that reduced survival of mountain pygmy possums can be related to declining snow cover and shorter winters. Studies conducted at Kosciuszko National Park revealed that the period of snow