Intraspecific Evidence for the Function of Single and Double Cones in the Teleost Retina

Retinal growth in young Sebastes diploproa involves the succession of three distinct cone patterns. Development of the final pattern with the loss of single cones occurs in close temporal association with a permanent migration from the surface to deep water. The results suggest that loss of single cones depends upon the change in environment and that the loss occurs through fusion to double elements.