The mammal known to lay eggs is the monotreme called the platypus. Native to Australia and Tasmania, the platypus is a unique species with characteristics of various animals: it has a duck-bill, webbed feet, and lays eggs like a reptile, despite being a mammal. Monotremes, including the platypus and the echidna, are remarkable for their method of reproduction, where they incubate eggs outside their bodies. The platypus also has a remarkable ability to detect prey through electroreception.