What does it mean when scientists say “an eagle can see a rabbit in a field from a mile away”. Is their vision automatically more zoomed in? Do they have better than 20/20 vision? Is their vision just clearer?

Question

What does it mean when scientists say “an eagle can see a rabbit in a field from a mile away”. Is their vision automatically more zoomed in? Do they have better than 20/20 vision? Is their vision just clearer?

In: Biology

Answer 1

Eagles have much better than 20/20 vision.

Your eyes are like looking at an old 800×600 monitor. The eagle’s eyes are like 4K HD. They have so many more pixels in the image that they can see the details even if the camera is much farther away.

That’s because birds of prey have 2-5x more cells that respond to light in their eyes relative to our eyes, and those cells have fewer interruptions than in our eyes. Their brain is specialized in processing those signals to see prey.