I tell my kid that his toy T-Rex says, "ROOOAAR." It occurred to me that I have absolutely no idea what a T-Rex sounded like. What other sounds might one of these creatures have made?
I like to think maybe it sounded like a 20 ton rooster.
Squeaky high notes, making you laugh, then he finds & eats you easily.
We literally haven't a clue as to what sounds the dinosaurs made. Mammals, including primates, felines, pachyderms, etc. are clearly influenced by the sounds of a potential mate or a competitor. Birds, the descendants of dinosaurs, also use vocalizations to declare intent. That impressive 'roar' ascribed by Hollywood may have been a less-than-impressive squeal!