Explain why fish would not be able to navigate their surroundings nearly as well if the light-absorbing molecules in their eyes were an order of magnitude larger or smaller than retinal.

Fishes use a different vision mechanism than mammals and other land animals. They have rods and cone photoreceptors to see the colorful visions and adjust their focal point by moving the lens closer to or away from their retina.

In the water bodies, a difference in the amount of light moves with the depth because water absorbs the light and this change occurs due to the optical nature of water.

The light bounces once it back in the retina, leads to the gain of the small packets of energy of light a second chance to be trapped by photoreceptors. However, vision remains blurry. The changes and distortion of the light-absorbing molecules present in the eyes of fishes make it tough to perceive a clear vision.

"a scientist studying a whale and its surroundings would need to understand the structure of atoms in case something was negatively affecting the whale or its surroundings."

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