When the first specimen of the Platypus reached Europe in 1798, it was received with incredulity by zoologists. With anatomical and morphological characteristics seemingly belonging to reptiles, birds, and mammals, it simply did not fit into the existing classifications. Further, it appeared to lack mammary glands and therefore could not be classed as a mammal, yet it had obvious mammalian characteristics such as fur and a single bone comprising the lower jaw. It was also noted that there was only one external body opening, the cloaca, into which the uteri, the gut, and the kidneys empty. Hence the name Monotreme (having one hole) applied by English anatomist Sir Everard Home in 1802. Put simply, the Platypus created more than its share of headaches for taxonomists.
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