Pygmy hippopotamus population that freely breeds in zoos around the world. Between 1970 and 1991 the population of pygmy hippos born in captivity more than doubled. The survival of the species in zoos is more certain than the survival of the species in the wild. In captivity, the pygmy hippo lives from 42 to 55 years, longer than in the wild. Since 1919, only 41 percent of pygmy hippos born in zoos have been male. While the common hippopotamus was known to Europeans since classical antiquity, the pygmy hippopotamus was unknown outside its range in West Africa until the 19th century. Due
Eastern pygmy possum (Krefft, 1863) (the mainland Australian subspecies). Vernacular names that have been used for this species include dwarf phalanger, minute phalanger, dwarf cuscus, pigmy phalanger, Bell's "Dromicia", opossum mouse, dusky "Dromicia", pygmy opossum, thick-tailed "Dromicia", mouse-like phalanger, common dormouse-phalanger, dormouse phalanger, common dormouse-opossum, dormouse possum, pigmy opossum, pigmy possum and eastern pigmy possum. A standard name finally arose via a committee of the Australian Mammal Society. Bones of this species are often recorded as fossils or sub-fossils from late Pleistocene and Holocene cave deposits in south-eastern Australia. It is incorporated into the fossil record because owls and/or quolls that have preyed