1. (1)In 1798, a few naturalists were skeptically probing a specimen delivered to the British Museum in London, looking for signs that a prankster had slyly stitched the bill of an oversized duck onto the pelt of a small furry mammal. (2)They didn’t know it, but they were examining the remains of a platypus, a web-footed mammal about half the size of a house cat. (3)Like the other mammals, the duck-billed platypus has mammary glands and hair. (4)However, like birds and reptiles, it has a cloaca, an enlarged duct through which reproductive cells, feces, and excretions from the kidneys pass. (5)The platypus also lays shelled eggs, as do birds and most reptiles; however, the young hatch before their embryonic development is complete. (6)And although the creature’s fleshy bill does appear ducklike, its broad, flat, furry tail resembles that of a beaver. (7)With its unusual traits, the platypus invites us to challenge preconceived notions of what constitutes “an animal.”
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