Opossum

General Opossum Information

The opossum is a medium sized marsupial commonly found in the United States. It is related to kangaroos, wombats, and koalas. This primitive group of mammals is the only marsupial that is found in North America.

This marsupial is of the Didelphimorphia order and it lives in the forested areas of North America. The Didelphimorphia order is common to the Americas and is actually one of the largest marsupials in the region of the Western Hemisphere. The order has at least 103 species categorized in 19 genera.

The Virginia Opossum

The Virginia opossum which is commonly known as possum used to inhabit parts of Central America and the southeastern US way before the European settlement in North America. They started expanding northward and westward during the 1900s. The opossum is therefore thought to have originated from the Southern jungles of America and entered the North during the period of Great American Interchange.

These animals can survive in diverse conditions because of their flexible diet, unspecialized biology, and reproductive habits. They have adapted well to staying close to people in both urban and suburban environments. Because of the few natural predators and abundance of shelter and food, these animals will continue thriving in human-occupied habitats.

Origin Of Opossums

The word ‘opossum’ was first recorded as aposoum by William Strachey and as opassom byJohn Smith. This was between 1607 and 1611. The two men borrowed the word from the Powhatan language which they encountered after settling in Jamestown, Virginia.

In Strachey’s notes, he describes opossum as the beast that is big and tastes like a pig. Smith, on his part, describes it as having the bigness of a cat with a head like a swine and a tail like a rat. The Powhatan word was derived from another Proto-Algonquian word which means a dog-like beast or a white dog.

In the midwest and southern parts of the US, opossum is commonly known as possum. The name possum was borrowed in Australia after the coming of the Europeans settlers. They used the term to describe the Australian marsupials closely related to kangaroos and of the Phalangeriformes suborder. The categorization of these animals into the Didelphimorphia order stems from the fact that they have two wombs.

Characteristics

Most members of the Didelphimorphs order are small and medium-sized animals that grow to a size of a house cat. A good number of them are semi-arboreal omnivores. Most members have long snouts, prominent sagittal crest, and a narrow braincase.

The upper dentition formula is 5.1.3.4 for the Incisors, Canines, Premolars, and Molars while the lower dentition formula is 4.1.3.4. Such a full jaw is not a common thing with mammals. For the case of opossum, their incisors are quite small, their canines are large while their molars are tricuspid.

The other characteristic with Didelphimorphs is that they have a plantigrade posture. This means that their feet are flat while on the ground. The hind feet of the opossum has an opposable digit but doesn’t have a claw. Just like monkeys, these animals have a tail.

Their fur is made of awn hair and just like other marsupials, their females do have a pouch. The opossum’s tail and parts of its feet have scutes while its stomach is simple and has a small cecum. The males have a forked penis similar to other marsupials and bearing twin glands.

As much as all the living opossums are opportunistic omnivores, the amount of vegetation and meat took by these animals vary according to species. Animals within the Caluromyinae species are essentially frugivorous. The Patagonian opossum and lutrine opossum essentially dine on other animals.

The yapok is quite unique being the only living marsupial with semi-aquatic capabilities. Yapok uses its webbed back limbs to dive into the water and search for crayfish and freshwater mollusks. Most of the opossums are scansorial and adapts well to living in trees and on the ground. Members of the Glironiinae and Caluromyinae species are mainly arboreal. The Metachirus, Didelphis, and Monodelphis species have adapted to ground living conditions.

Habitat

The Opossum species are commonly found in South, Central, and North America. The Virginia species live in the regions of Central America and Canada while the other species live in the south. Their habitats vary much except for the Virginia species which live in wooded areas.

It is quite common to find an opossum living in or under a building. In most cases, they will occupy the space for 2 – 3 days and move to somewhere else. They are usually attracted to dry, warm, dark and easily defended areas during the mating season. If the setting is favorable enough they will stay there for the entire nesting season.