Originally Posted by cody3856
This was a question I've been wondering for a long time. When they made Jurassic Park, how did they know what T-Rex sounded like? Also in Jurassic Park 3, how did they figure out that the Spinosaurus had a sail on its back?
As for the sound of the t-rex, and all the other dinosaurs too, it is a complete guess. Basically they just created a sound that they thought sounded good for the movie. For the t-rex, they actually combined the sounds of a bull elephant, a grizzly bear, and a lion.
The spinosaurus' sail though, is based on fossil evidence. No complete spinosaurus skeletons have been found, but as was already mentioned, the sail is the best theory as to my the vertebrae were so tall. Check out the wikipedia page for spinosaurus for more info on that.