Ringtail and Greater Gliding Possums: Pseudocheiridae

Ringtail and greater gliding possums are marsupial mammals. They range in length from 13 to 37 inches (32 to 95 centimeters) and weigh between 4 ounces and 79 pounds (115 grams to 22.5 kilograms). In this family there are two distinct types of possums. The greater gliding possums have a membrane, or thin layer of skin, between their front legs and their back legs. They spread their arms and legs when they leap from tree to tree and the membrane acts like a parasail or parachute and allows them to glide. The other group, known as the ringtail possums, is much different. They do not have this membrane, and their legs are short and stocky. The greater gliding possums can be up to 37 inches (95 centimeters) long, including their long tail, and weigh up to 42 ounces (1,200 grams).

Ringtail possums are furry and can be light gray, cream, orange, or dark brown in color. One species, the green ringtail, even looks green because of a combination of yellow, black and white fur. Ringtail possums have short round ears and a tail that is bare near the end.

Because they are marsupial mammals, ringtail and greater gliding possums are different from most familiar mammals such as cats, horses and humans. These familiar mammals are all eutherian (yoo-THEER-ee-an) mammals, which means they have a well-developed placenta. A placenta is an organ that grows in the mother's uterus, womb, and lets the mother and developing baby share food and oxygen. Marsupial mammals do not have this type of placenta. Because of this, they give birth to young that are not physically developed enough to be able to survive on their own. Instead, the young are carried around either in a pouch or attached to the mother's teats, or nipples, on her underbelly until they have completed their development.