Platypus, small amphibious australian mammal noted for its odd combination of primitive features and special adaptations, especially the flat, almost comical duck-beak-like bill. Sep 4, 2023overall, the platypus is a true marvel of nature, with its unique combination of features and adaptations. Dec 23, 2025it possesses a duck-like bill, webbed feet, and a sleek, streamlined body, which are adaptations suited for its semiaquatic lifestyle.