The platypus is highly adapted to its semi-aquatic lifestyle, weighing between 1.3 to 3.7 kg for females and up to 6.6 kg for males, with a total length around 50 cm.
When the first specimen was brought to Europe in 1799, naturalists assumed it was a hoax created by combining parts of different animals together. Physical Characteristics and Adaptations
What Scientists Learned from the Oldest Wild Platypus Ever Found
