Did you know that North America only has one native marsupial? It’s called the Virginia Opossum, not to be confused with the type of Possum that lives in Australia. The opossums we have here are a little bit smaller and can be seen at night sometimes foraging around for supper.
Many folks are alarmed when they see a giant rat-like creature eating from a pet’s food bowl that may have been left out for the local pets that may roam. But don’t panic, it’s only an opossum. Opossums are in the marsupial family, which means they have a pouch in which to carry young joeys until they grow big enough to move out of the pouch and hitch a ride on mom’s back as she forages.
When opossum are born, they are only about the size of a lima bean. After mom has given birth, the youngsters move into mom’s pouch, which is called a marsupium. There, they will stay attached to a nipple for about 2 months, and then will migrate to mom’s back and ride around with her for awhile as she forages. Opossums are rather beneficial to have around, as they tend to remove leftovers from unfortunate animals that have had a run in with a car. They are not harmful and really would rather be left alone to perform clean up duty. If an opossum is cornered, it may indeed “play dead” in hopes that the intruder will go away, or it may stand it’s ground and open it’s mouth to show off a toothy grin of the 60 some teeth it has while making a hissing noise. This is merely a threat display, and often it’s impressive enough to ward off any enemies. But if left alone, the opossum may shuffle off quietly after the threat is gone to go about it’s business, cleaning up those leftovers. When on opossum “plays dead” it will lay on its side, completely still, head lolled over showing off those impressive teeth, while drool seeps out of the sides. They may also excrete a sticky, yellow, mucous-like substance from underneath the tail. It’s not a pretty sight, but often this leads to the possible “predator” leaving the area so the opossum can recover and get away.
Opossums are very primitive mammals. In fossil records, opossums (also known as didelphid marsupials) have been found to exist during some of the time of the dinosaurs. During this time, the late cretaceous period, small marsupial mammals and other primitive placental mammals lived alongside the likes of hadrosaurs, ankylosaurs, ceratopsians such as triceratops, and tyrannosaurs. This summer we have brought back the dinosaurs for visitors to enjoy and when you come to visit the Museum, perhaps you will see one of these primitive mammals, the Virginia opossum, along with the dinosaurs. When going out on to the nature trail, watch out for the Dilophosaurus that awaits it’s next victim as you exit the building. I hear he likes to watch the visitors and keep a close eye on what they are doing. Watch out though, he may have a surprise in store for you!