Scientists have discovered a lone tooth in Queensland, Australia that has led to the classification of a new, giant, extinct platypus. They aren’t completely certain of the fossil’s age, but they’re guessing between 5 and 15 million year old. The size of the tooth suggests the animal was more than 3 feet long—twice the size of it modern predecessor. They believe like today’s platypuses, it was an aquatic mammal and due to the size of its teeth it probably fed on small vertebrates like frogs and small turtles. What’s interesting about the discovery is that scientists had previously thought than only one species of the platypus lived at a time. However, the newly discovered species would have been a side-branch—which was bigger than the others. So now scientists say the platypus evolution wasn’t so linear after all.