A platypus (Ornithorhynchus anatinus) pauses for a moment after being released by scientists into the Little Yarra River, its home stream in Victoria, Australia. (Credit: Douglas Gimesy)

With the bill of a duck, the body of an otter, and the tail of a beaver, the platypus (Ornithorhynchus anatinus) has a long history of confounding the humans who’ve encountered it. Early European settlers took to calling the strange, semi-aquatic mammals they found living in eastern Australian streams “duck