It is a strange & true fact that an ostrich’s eye is bigger than its brain.The ostriches are big birds despite the tiny brains & they are closely related to dinosaurs, and have similar to a T-Rex. The ostrich’s eyes are about the size of billiard balls & they have so much room in the skull that the ostrich’s brain is actually smaller than those any eyeballs.So thats why the ostrich’s have tremendous running speed & it tends to run in circles.