|MadSci Network: Zoology|
Ronald, At an etymological level, your question can simply be answered 'yes'. Possum is just an abbreviated form of the 'proper' name of opossum. It originally derived from a Native American word for the animal, and was transferred to South America and Australia as a name for similar animals there. Biologically, the question is more complicated because there are many species of opossums, but the answer is still basically 'yes'. The one you are probably familiar with is the Virginia or North American Opossum, Didelphys virginiana, but there are lots more of its relatives in Central and South America. There are even more of its relatives in Australia, but the S American and Australian possums have differentiated into two groups because they have been isolated for millions of years. All opossums are marsupials, pouched mammals considered primitive compared to the other mammal groups. The Virginia opossum has the distinction of being the only marsupial in North America. Because there are so many different kinds, the word possum/opossum does not have a well-defined biological meaning. It means something like 'small arboreal insectivorous marsupial'.
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