I don't remember where I read it, but I read a lot, and subscribe to Cat Fancy magazine, as well as Cat Watch, which a newsletter for a major veterinery school and research center. Studies have found that cats either don't focus on or don't notice things that are distant; they creep up close to their prey before pouncing. Also. prey runs along the grund in fast scampering movements, so cats have evolved to focus on that movement. Anything running by close enough to pounce on will trigger the prey drive. Movement too far away to catch before it gets away won't trigger this response. Anything extremely distant has no meaning in the cat's world. The prey (or threat) is too far off to matter. The ground if far away, but that bird zooming past close to the building triggers a reflexive response.
That cat's do not see or pay attention to distant things was proven in vet studies. How this came about because of how they hunt is my own logical deduction.
