Though generally nocturnal, opossums vary somewhat in behavior, as well as in habitat and appearance. The species most familiar to those in North America is the Virginia, or common, opossum, which is the only species that lives at such latitudes. This animal is often about the size of a domestic cat, but has a long pointy nose, rounded ears, and a long prehensile tail that lacks fur. Though adaptable, the common opossum prefers wooded areas, often establishing its den in tree stumps or hollows. The yapok, or water opossum, however, which ranges from Mexico to Argentina, has evolved in such a way that it is best suited to a very different lifestyle than that of the common opossum. Its webbed toes, watertight pouch, and dense, oily pelt are ideal for the animal’s semi-aquatic existence.