Distal Caudal vertabra (one of the tail bones) Spinosaurus Age: Cretaceous, Cenomanian stage (approximately 100 million years ago) Location: The Kem Kem Formation, Morocco
Spinosaurus were semi-aquatic dinosaurs. Their teeth were well adapted for catching fish. Recent research into the movement and structure of spinosaurs' caudal vertebrae suggests that they were strong tail swimmers. If true this is an adaptation which has not ben observed in any other family of dinosaurs.