The Natural History of Invertebrate Visual Pigments

Abstract

The invertebrates comprise a large and diverse array of animals. In lower forms responses to light are frequently marked but are mediated by relatively simple eyes (ocelli) or anatomically unspecialized receptors in the dermis or nervous system. In two phyla, however, conspicuous image-forming eyes have evolved. For obvious reasons, most of our knowledge of photoreception in the invertebrates has been derived from those species with a well developed visual apparatus.