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Is the platypus, this incompletely evolved Australian mammal, viviparous or oviparous?
The platypus is one of the most primitive mammals. It is an incompletely evolved mammal, with very few species; within its genus there is only one animal, the platypus, and it is also one of the lowest mammals. The platypus has a beak and feet like a duck, while its body and tail resemble those of a beaver.