What Does the Pecten See?

Zoologists in the last century were very keen observers of nature, and they had considerable ability in drawing anatomically accurate pictures of the animals they worked with. The drawing at the left is based on Lankester's (1906) microscopic studies.

While the scallop's eye is remarkable in its detail and shows many  similarities to our eye, it is not known how images of objects are interpreted by  the scallop's central nervous ganglia. Most authorities have stated simply that the scallop responds to light and to moving objects.

From an evolutionary viewpoint, one might expect from the complexity of these structures --and ringed around the mantle edges, as they are-- that the scallop could process fairly complex imagery.