Marsupialia Class: Mammalia Two sub-classes Egg-laying mammals, monotremes, and mammals who give live birth, therians Therians are further divided into two infraclasses Eutherians, placental mammals and the Marsupials, animals with pouches (marsupium)

Marsupials, history First arose during the Paleocene 65 million years ago A geologic epoch that defines the end of the last mass extinction event at the end of the Cretaceous (the end of the age of dinosaurs)

Marsupials, distribution Two divisions of the 334 species of marsupials American marsupials 113 species in South and Central America One species in North America Australian marsupials More than 200 species

Marsupial distribution

Australian Marsupials

American Marsupials Central American Wooly Opossum South American Bushy-Tailed

Opossums More than 60 species of opossum Opossum is an American Algonquian word meaning “white dog” North American Virginia opossum

Opossums The only North American species is the Virginia opossum Commonly called 'possums' in the American southeast, the possum is technically a species of smaller opossum indigenous to Australia

Opossums Young are as small as honeybees when they are born Gestation is only about 2 weeks Young crawl into the pouch and nurse for 70- 100 days before emerging from the pouch

Opossum immunity Particularly robust Resistant to among other things, snake venom and ricin Rabies is very rare in opossums, less than 1 in 800 animals affected

Diet Opportunistic eaters with a varied diet

Playing possum An involuntary reaction, similar to fainting In response to stress The teeth are bared, the eyes half-closed and gives all appearance of a dead animal Usually awake after 40 minutes but can last up to 4 hours