Two eyes for two purposes: in situ evidence for asymmetric vision in the cockeyed squids Histioteuthis heteropsis and Stigmatoteuthis dofleini.

ABSTRACT: The light environment of the mesopelagic realm of the ocean changes with both depth and viewer orientation, and this has probably driven the high diversity of visual adaptations found among its inhabitants. The mesopelagic 'cockeyed' squids of family Histioteuthidae have unusual eyes, as the left and right eyes are dimorphic in size, shape and sometimes lens pigmentation. This dimorphism may be an adaptation to the two different sources of light in the mesopelagic realm, with the large eye oriented upward to view objects silhouetted against the dim, downwelling sunlight and the small eye oriented slightly downward to view bioluminescent point sources. We used in situ video footage from remotely operated vehicles in the Monterey Submarine Canyon to observe the orientation behaviour of 152 H

SUBMITTER: Thomas KN 

PROVIDER: S-EPMC5312019 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature