Opossum -- Eaten During the Great Depression

Opossum at a glance 

The opossum is a successful colonizer and survivor in diverse locations

Opossum, Close-up Portrait, USA Photographic Print
Hamblin, Mark
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Didelphimorphia is the order of common opossums of the Western Hemisphere. They are commonly also called possums, though that term is also applied to Australian fauna of the suborder Phalangeriformes.

The Virginia Opossum is the original animal named opossum. The word comes from Algonquian wapathemwa. Opossums probably diverged from the basic South American marsupials in the late Cretaceous or early Paleocene. A sister group is Paucituberculata (shrew opossums).

Their unspecialized biology, flexible diet and reproductive strategy make them successful colonizers and survivors in diverse locations and conditions. Originally native to the eastern United States, the Virginia Opossum was intentionally introduced into the West during the Great Depression, probably as a source of food.

Its range has been expanding steadily northwards, thanks in part to more plentiful, man-made sources of freshwater, increased shelter due to urban encroachment, and milder winters. Its range has extended into Ontario, Canada, and it has been found farther north than Toronto.

Virginia Opossum at a glance 

This opossum is a solitary and nocturnal animal about the size of a domestic cat!

Virginia Opossum in Tree USA Photographic Print
Stone, Lynn M.
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The Virginia Opossum (Didelphis virginiana), commonly known as the North American Opossum, is the only marsupial found in North America north of the Rio Grande River. A solitary and nocturnal animal about the size of a domestic cat, it is a successful opportunist and is found throughout Central America and North America east of the Rockies from Costa Rica to southern Ontario (it was also introduced to California in 1910, and now occupies much of the Pacific coast); it seems to be still expanding its range northward. Its ancestors evolved in South America, but were enabled to invade North America in the Great American Interchange by the formation of the Isthmus of Panama about 3 million years ago. It is often seen near towns, rummaging through garbage cans, or lying by the side of the road, a victim of traffic.

Opossum Sister Group is the Shrew Opossum 

Shrew opossums are about the size of a small rat! Not cat!!

Opossum, Tropical Andes, Colombia Photographic Print
Robles Gil, Patricio
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The order Paucituberculata contains the six surviving species of shrew opossum: small, shrew-like marsupials which are confined to the Andes mountains of South America. It is thought that the order diverged from the ancestral marsupial line very early. As recently as 20 million years ago, there were at least seven genera in South America. Today, just three genera remain.

They live in inaccessible forest and grassland regions of the High Andes. Insectivores were entirely absent from South America until the Great American Interchange three million years ago, and are currently present only in the northwestern part of the continent. Shrew opossums have lost ground to the these and other placental invaders that fill the same ecological niches. Nevertheless, the ranges of shrew opossums and insectivores overlap broadly.

The Origin of the Opossum -- Late Cretaceous Period 

Opossums probably diverged from the basic South American marsupials in the late Cretaceous Period

The Cretaceous is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows on the Jurassic period and is followed by the Paleogene period of the Cenozoic era. It is the youngest period of the Mesozoic era, and at 80 million years long, the longest period of the Phanerozoic eon. The end of the Cretaceous defines the boundary between the Mesozoic and Cenozoic eras. In many languages this period is known as "chalk period".

The Cretaceous was a period with a relatively warm climate and high eustatic sea level. The oceans and seas were populated with now extinct marine reptiles, ammonites and rudists; and the land by dinosaurs. At the same time, new groups of mammals and birds as well as flowering plants appeared. The Cretaceous ended with one of the largest mass extinctions in Earth history, the K-T extinction, when many species, including the dinosaurs, pterosaurs, and large marine reptiles, disappeared.

Wow! That Opossum is a Marsupial -- Really? 

Did you know this about the opossum?

Brushtail Opossum at Dusk, New Zealand Photographic Print
Bernhard, Tobias
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The opossum is a small to medium-sized marsupial, with the largest about the size of a large house cat, and the smallest the size of a mouse. They tend to be semi-arboreal omnivores, although there are many exceptions. Most members of this taxon have long snouts, a narrow braincase, and a prominent sagittal crest.