The Platypus is a mammal.

True. The platypus is a mammal because it’s warm-blooded, covered in fur, and feeds its young with milk produced by mammary glands (though it lacks nipples—milk is secreted through skin pores). What makes it memorable is that it’s one of the few egg-laying mammals, part of a tiny group called monotremes (along with echidnas). Found in eastern Australia and Tasmania, the platypus also has a duck-like bill that detects electrical signals from prey, webbed feet for swimming, and males have a venomous spur on their hind legs. Remember: “If it makes milk, it’s a mammal”—and the platypus is the famous exception that lays eggs while still checking all the mammal boxes.