Spinosaurus

The largest predatory dinosaur to ever walk on Earth sported a massive sail that rose from its back. Its bony, muscular tail wouldn't have had the same [blank] of a whale or fish, and the heavy sail might have been more of an obstacle than a useful tool. If Spinosaurus was plunked down in deep water, the results wouldn't have been very pleasant. This anatomical clue suggested Spinosaurus was "semiaquatic" and [blank] into the shallow waters along river banks for its prey. Similar to some lizards today that have spine-supported sails, Spinosaurus likely used its sail during competition and courtship. Intriguingly, the dinosaur likely lived along marine and freshwater [blank] like other semiaquatic reptiles, but it's not something that any other extinct or extant large aquatic vertebrates like ichthyosaurs or sea turtles [blank] . So Spinosaurus would have prowled along coastal and inland waterways, ambushing prey as it waded into shallow waters.