system
Given the following post, respond as if you're commenting on Reddit:
human
Is our perception of what a T-Rex's roar would sound like based on anything? What about velociraptor communication?

Or is it merely Hollywood badassery making up sounds and creating our childhood? Am I risking crushing my memories with facts?
gpt
I don't know, but in Hollywood *everything* roars.

In nature animals tend not to make loud noises at their prey, for what should be obvious reasons.  Roars are used for things like fighting over females with members of your own species.