The eagle has more cones, while the owl has more rods.
Explanation
The retina of the eye acts as a screen where images are formed. It contains two types of photoreceptor cells: rods and cones. Rods are sensitive to light intensity and function best in dim light (scotopic vision), while cones are sensitive to bright light and color (photopic vision).Detailed Analysis:
- Diurnal Birds (e.g., Eagle): These birds are active during the day and require high visual acuity and color perception to spot prey from distances. Consequently, their retinas contain a high concentration of cones and fewer rods.
- Nocturnal Birds (e.g., Owl): These birds are active at night and require high sensitivity to detect low levels of light. Their retinas are dominated by rods to maximize light absorption. While they possess a large cornea and pupil to admit more light, the retinal composition specifically favors rods over cones.
Key Takeaway: Rods facilitate night vision by detecting light intensity, whereas cones facilitate day vision by detecting color and fine detail. Therefore, nocturnal animals have rod-dominated retinas, and diurnal animals have cone-dominated retinas.