The platypus (Ornithorhynchus anatinus) is a creature seen as many as a very simple one, that has had minimal evolution. But it is one that's features are incredibly well suited for its lifestyle, and are also quite unique for a mammal. Like the echidna, the platypas, although a mammal, has several kew characteristics that resemble a reptile. These include the ability to lay eggs, cervical ribs, and that there is localisation of ascorbic acid synthesis in the kidney. The platypus is a truely puzzling animal and is one of Australia's most unique mammals