. All four limbs were modified as paddles,
with the front pair usually larger than the rear ones. These were used mainly for steering,
manoeuvring and braking. A dolphin-like fin on the back prevented the animalleanin~ or
rolling to the side. The caudal vertebrae (tail backbones) angled down at the end to support
a large upright fin, similar to the tail of a fish. Swishing this from side to side provided