Wow. Chitons move very slowly but can clamp down tightly onto their substrate. The video suggests they can detect predators at a distance of at most 2m, so the eyes allow them to clamp down "just in time", leaving only their armour plating exposed to the predator.
Interestingly, the lens in each eye is made of the same material as the shell itself, but the grains of the material are aligned parallel, to allow light to pass to the retina. Grains in the rest of the shell are randomly oriented, resulting in opacity.
Interestingly, the lens in each eye is made of the same material as the shell itself, but the grains of the material are aligned parallel, to allow light to pass to the retina. Grains in the rest of the shell are randomly oriented, resulting in opacity.