“Optimized by Phototropic Chromatophores”Here is how a 2001 paper described this finding:
The lens array is designed to minimize spherical aberration and birefringence and to detect light from a particular direction. The optical performance is further optimized by phototropic chromatophores that regulate the dose of illumination reaching the receptors. These structures represent an example of a multifunctional biomaterial that fulfills both mechanical and optical functions.
Designed? Optimized? An example of a multifunctional material? As one researcher exclaimed, “It's astonishing that this organic creature can manipulate inorganic matter with such precision - and yet it's got no brain.” Another research explained just how unique this design is:
It's bizarre - there's nothing else that I know of that has lenses built into its general body surface.
Nothing in biology makes sense in the light of evolution.