The marsupial family Peramelidae contains all of the extant bandicoots. They are found throughout Australia and New Guinea, with at least some species living in every available habitat, from rainforest to desert. Four fossil peramelids are described. One known extinct species of bandicoot, the pig-footed bandicoot, was so different from the other species, it was recently moved into its own family. Peramelids are small marsupials, ranging in size from the mouse bandicoot, which is 15-17.5 cm long, to the giant bandicoot, which at 39–56 cm in length and up 4.7 kg in weight, is about the size of a rabbit. They have short limbs and tails, smallish, mouse-like ears, and a long, pointed snout. Peramelids are omnivorous, with soil-dwelling invertebrates forming the major part of their diet; they also eat seeds, fruit, and fungi. Their teeth are correspondingly unspecialised, with most species having the dental formula 5.1.3.43.1.3.4 Female peramelids have a pouch that opens to the rear, and contains eight teats. The maximum litter size is, therefore, eight, since marsupial young are attached to the teat during development, although two to four young per litter is a more typical number. The gestation period of peramelids is the shortest among mammals, at just 12.5 days, the young are weaned around two months of age, and reach sexual maturity at just three months. This allows a given female to produce more than one litter per breeding season, and gives peramelids an unusually high reproductive rate compared with other marsupials.