The cockeyed squid Histioteuthis heteropsis

Histioteuthis heteropsis, the strawberry squid, gets its common name from the berrylike appearance of its brightred body speckled with numerous luminescent photophores. This animal is also called the cockeyed squid due to a remarkable eye dimorphism. The left eye of the adult squid can measure more than twice the diameter of the right eye, a curious trait not known in any other family of bilaterally symmetrical animal. In its natural habitat, Histioteuthis is almost always observed in an oblique position with the larger eye facing slightly upward and the smaller eye facing slightly downward. Researchers believe the large eye with its yellow lens is specialized for breaking the counterillumination (a camouflaging technique) of prey items in the water column above the squid, while the small eye is specialized for picking up bioluminescent flashes from predators or prey items down below. Using MBARI s ROVs, researchers have observed the cockeyed squid in the midwater region at depths from 3001000 m (9003000