Pygmy hippopotamus occur. The common hippopotamus gives birth and mates only in the water, but pygmy hippos mate and give birth on both land and water. Young pygmy hippos can swim almost immediately. At birth, pygmy hippos weigh 4.5–6.2 kg (9.9–13.7 lb) with males weighing about 0.25 kg (0.55 lb) more than females. Pygmy hippos are fully weaned between six and eight months of age; before weaning they do not accompany their mother when she leaves the water to forage, but instead hide in the water by themselves. The mother returns to the hiding spot about three times a day and calls
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