Iain McGilchrist, in The Master and His Emissary, says we use our two cerebral hemispheres differently. The hemispheres, remember, control the opposite sides of the body, so the right control the left hand, and the left hemisphere control the right. It’s the same with vision where the right field of vision is the responsibility of the left hemisphere and the left field of the right hemisphere. I’m simplifying here, but you get the idea. In birds which have their eyes on the sides of their heads instead of in the front of their faces, each hemisphere controls the opposite eye but the idea is the same.
The right hemisphere supports a broad, vigilant attention. In a bird the left eye, therefore, is taking everything in to be aware of predators.
See how this duck is looking at me?
They use the left hemisphere to focus the right eye on details….for example, when picking out food.
There’s something else interesting about the field of view of interest to each hemisphere.
In we humans, the right hemisphere is more interested in what is far from us….
while the left is more interested in what is close up….