A wallaby is any of about thirty species of macropod . Essentially, a wallaby is any macropod that isn't considered large enough to be a kangaroo and has not been given some other name. There is no fixed dividing line. In general, a wallaby is smaller and has a stockier build than a kangaroo; a wallaroo is any of a few species somewhat intermediate in size between a wallaby and a kangaroo. Very small forest-dwelling wallabies are known as pademelons and dorcopsises.
Bison is a taxonomic genus containing six species of large even-toed ungulates within the subfamily Bovinae. Only two species are still extant—the American and European bisons.
The bison is often mistakenly called "buffalo", but the true buffalo is native only to Africa and Asia.
In Australia we have water buffalo that are creating environmental havoc in northern parts of Queensland and some parts of the Northern Territory
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