New bones suggest Spinosaurus is the only known aquatic dinosaur.
A swimming dinosaur: The tail of Spinosaurus
A new fossil of one of the most unusual dinosaurs, Spinosaurus aegyptiacus, suggests it was a swimming predator powered by a fin-like tail. The find comes after decades of debate on how much of its life Spinosaurus would have spent in the water, and how reliant they might have been on aquatic prey. Paleontologist Nizar Ibrahim has been working at the dig site in the Sahara and describes his amazement at the unique tail bones they found under the rock and sand.