An eagle can spot a rabbit from 2 miles away.

Eagles possess some of the most sophisticated visual systems in the animal kingdom. While a human with perfect vision has 20/20 sight, a bald eagle typically has 20/4 or 20/5 vision. This means an eagle can see an object from 20 feet away that a human would need to be 4 or 5 feet away to perceive clearly. This incredible acuity is due to the density of cones in their retina. The fovea is the part of the eye responsible for sharp central vision. In humans, the fovea contains about 200,000 cones per square millimeter. In contrast, eagles have roughly 1,000,000 cones per square millimeter. This high density allows them to resolve fine details at extreme distances, such as a small rodent moving in tall grass from a height of several hundred feet. Eagles also have two foveae in each eye, whereas humans only have one. This allows them to focus on both forward and side objects simultaneously. Their ability to detect ultraviolet light helps them track prey by spotting the UV-reflective urine trails left by small mammals. Research published by the Smithsonian Institution confirms that these adaptations are essential for their survival as apex aerial predators.