“Another incredible marvel of design that only an intelligence far greater than ours could have produced.” Admin
Human eyes are well-designed to see objects using light transmitted through air, but not through water, because light travels at a different speed through the two media. However, intertidal-dwelling marine mollusks called chitons can see equally well in both environments. How did they acquire this unusual ability?
Chitons scour intertidal rocks for algae meals. Eight integrated shell-plates cover their backs, and a muscular foot allows them to cling with surprising strength to the rocks they traverse. A recent study explored their unique dual-mode eye design. How do they see in both air and water without switching out eye lenses, and is this an “adaptation,” as suggested in a summary in ScienceNOW?1
Researchers publishing in Current Biology tested chiton eye lenses and discovered they were the first ever known to be made of the hard mineral aragonite.2 Chiton shells are also made primarily of aragonite, but the use of this material in an eye lens turns out to be an elegant solution to the problem of forming quality images in either air or water.