|MadSci Network: Zoology|
Both the platypuses (Ornithorhynchidae) and the spiny anteaters, or echidnas (Tachyglossidae), are monotremes. Monotremes have fur and warm blood and produce milk like all other mammals, but they lay eggs like reptiles! There are some other differences in their skeletons that are important to zoologists (people who study living animals) and paleontologists (people who study long extinct animals), but almost as remarkable as the egg-laying is that some platypuses have venom glands in the spurs on their ankles! While many reptiles can produce venoms, platypuses are the only venomous mammals. In a way, monotremes can be seen as mammals that have retained many of the characteristics of reptiles.
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