In *Jurassic Park*, in the scene when the T-Rex escapes from the paddock and attacks the broken down cars, Dr. Grant tells Ian Malcolm not to move, as the T-Rex's visual acuity is based on movement. 

How do we know this to be true? Was this an invention of Michael Crichton's for the novel, or is this an accepted theory in palaeontology?

[![enter image description here][1]][1]


  [1]: https://i.sstatic.net/YQZsN.jpg