From World Book 2002:
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Possum is a type of furry mammal that lives in the trees of Australia, New Guinea, and nearby islands. Possums are marsupials--that is, the females give birth to young that complete their development while attached to the mother's nipples. Like most marsupials, young possums develop while carried about in a pouch on their mother's abdomen. Both possums and opossums are marsupials, but they are not closely related.
Possums move about at night and sleep during the day. They have handlike hind feet that help them grasp the branches of trees. Possums eat mainly blossoms, fruits, insects, and sap. The animals have black, brown, gray, tan, or white fur.
There are about 40 species of possums. The brush-tailed possum lives in Australian cities and raids fruit trees and garbage cans for food. Brush-tailed possums weigh from 3 to 11 pounds (1.4 to 5 kilograms). Other large species of possums, called cuscuses, weigh as much as 8 pounds (3.4 kilograms). The mouse-sized honey possum has a long, tube-shaped mouth and feeds on nectar and pollen. Pygmy possums may weigh as little as 1/4 ounce (8 grams). Several species of possums, called gliders, have large folds of skin between the front and rear legs on each side of the body. When the legs are spread, this skin serves as wings for gliding.
Scientific classification. The brush-tailed possum and cuscuses belong to the family Phalangeridae. The honey possum makes up the family Tarsipedidae. Pygmy possums belong to the family Burramyidae. Most gliders are in the family Petauridae.
Contributor: Michael L. Augee, Ph.D., Senior Lecturer, University of New South Wales.
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Opossum, pronounced uh PAHS uhm, is any member of a family of furry mammals that live in the Western Hemisphere. The female opossum carries its young in a pouch on its abdomen. Opossums, kangaroos, and other mammals that give birth to extremely undeveloped young are called marsupials. Opossums are the only marsupials that are native to North America. They live from Ontario in Canada southward into South America.
There are many species of opossums, most of which live in Central and South America. Small, tree-dwelling murine opossums resemble mice. Woolly opossums have thick, soft fur. Another kind of opossum, the yapok, is the only marsupial that is adapted for living in water. Its webbed feet help make it a good swimmer.
The common opossum is the only kind of opossum found in the United States. This species grows about as big as a house cat. It has rough grayish-white hair, a long snout, dark eyes, and big hairless ears. This opossum has a long tail that does not have much hair on it. The animal can hang upside down by wrapping its tail around a tree branch. This opossum has 50 teeth, more than any other North American mammal. Its teeth and claws are sharp. Opossum tracks are easy to recognize because the animal has long, widely separated toes.
Opossums are born in groups of from 5 to 20. At birth, an opossum is only about as big as a kidney bean. The female opossum carries its tiny babies in a pouch on the outer skin of its abdomen for about two months after birth. After leaving the pouch, the young stay near the mother for several more weeks. When they can take care of themselves, the young opossums go off on their own.
Opossums hunt at night. They eat almost any kind of animal or vegetable food. When in danger, opossums sometimes "faint" and appear to be dead.
Scientific classification. Opossums make up the opossum family, Didelphidae. The scientific name for the common opossum is Didelphis marsupialis.
Contributor: Frank B. Golley, Ph.D., Research Professor of Ecology, Institute of Ecology, University of Georgia.
