Aussie possums are very different from American opossums. (We spell it both ways; Australians don't spell it with the "o.") American opossums come in just one variety, the Virginia opossum (Didelphis virginiana). They are slow—I've heard a top speed of 1.8 mph; they are omnivorous, meaning they eat just about anything; they have hairless tails; and they have the ability to "play possum," meaning they have an involuntary defense mechanism that sees them going into a comalike state when in danger. Aussie possums, which are only very distantly related*, come in 27 different species; they're all quick and nimble; they're herbivores; almost all have fur-covered tails; and they don't have the playing possum defense mechanism. They are, in other words, very different creatures.
Australian possums are in fact only called "possums" because they were deemed to be similar to America opossums when first encountered by Europeans in the 1700s.
My possum came silently along the top of the fence between our building and the next. I rushed to get my camera, and, in my usual artistic style, I got a great shot of it:
I was however, able to identify the little bugger:
Like all ringtail possums, the common ringtail possum has a strongly prehensile tail which acts as a fifth limb, and which is carried tightly coiled when not being used. It can be distinguished from the brushtail by the light covering of fur on its tail, as well as the white tail tip.The picture shows the white tail tip, which can be quite long.
* All marsupials on the planet are believed to have descended from a marsupial creature that first appeared some 100 million years ago (maybe many more) on land that later became North America. (It was still attached to Europe and Asia at the time.) The creature prospered and migrated to South America, which then migrated itself, south to the supercontinent Gondwana, of which Australia was still a part. Over the millennia the marsupials expanded into Australia, which later broke off and became its own continent. Over the eons they evolved to become the 220-odd different marsupials that populate the continent today, which means that all those Aussie possum species, and all its other marsupials, even the mighty kangaroo—and our Virginia opossum as well—evolved from that small, long ago North American marsupial. (And there are still 13 species of marsupial in South America.)
Now here's a bonus pic of the Christine looking very Parisian on our veranda: