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Histioteuthis heteropsis, the strawberry squid, gets its common name from the berry-like appearance of its bright-red 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 300-1000 m (900-3000 ft). They eat shrimp, fishes, and even other squid: in turn, they make a tasty meal for larger squid and fishes. 00:00 The red mantle is dotted with bioluminescent photophores creating a strawberry-like pattern. 00:11 Small right eye and large left eye with a yellow lens. 00:23 Close up of dimorphic eyes. 00:32 ‘J-pose’ and ‘straight-arms’ postures. 00:54 ‘Ratcheting’ behavior. This video was posted to accompany a recent publication on the behavior and bizarre eyes of this squid led by an alumnus of the MBARI summer internship program. Two eyes for two purposes: In situ evidence for asymmetric vision in the cockeyed squids Histioteuthis heteropsis and Stigmatoteuthis dofleini. Kate Thomas, Bruce Robison and Sönke Johnsen. Philosophical Transactions B, Feb. 13, 2017. DOI: # Find more information here
