About 250 million years ago, long before the arrival of the dinosaurs, a ten-centimetre-long amphibian with a flat, compact body emerged on the supercontinent Pangaea. Unlike its salamander-like ancestors, it only had a small tail supported by six vertebrae. Triadobatrachus is regarded as the world’s first frog. It was already a strong swimmer with its powerful legs. One can clearly see how they prefigured their descendants’ jumping legs.