Meet the star of Jurassic Park III: Spinosaurus! Seriously, though, it was nothing like it was in the movie. Or at least that's what my brother says. He says it only ate fish and Giganotosaurus was bigger. He's right about the fish part, but not the Giganotosaurus part. He just can't accept the fact that Spinosaurus was really the biggest theropod discoverd. It could grow to a length of 60 feet long, be 16 feet high, and weigh 7 tons!