Life on this planet would be very different if it were not for the eye. The "eye" of any species is a fascinating structure. It is a major reason for the way that life has evolved on Earth. The first animal to have an actual eye was the Trilobite. See our company logo. This animal was one of the first of the Arthropods, the phylum that contains crabs, shrimps, and insects. We refer the reader to a most fascinating book: "In The Blink Of An Eye" by Dr. Andrew Parker.

Reference: in the Blink Of An Eye, Andrew Parker, Perseus Publishing, Cambridge, MA.