If T-rex's vision is based upon movement why don't they run into trees and knock themselves out?? Please Register or Log in to view the hidden image!
I think you are misunderstanding what is meant by the term 'based on'. Most animals notice movement so you could say their vision is also based on movement. If you walk up on a deer grazing and it raises it's head and you freeze it will stare at you trying to figure out what exactly you are, they will stare quite a long time and if you move they will bound off. It isn't that they cannot see objects that do not move it is just that they do no worry about them.
