The visual ecology of a deep-sea fish, the escolar Lepidocybium flavobrunneum (Smith, 1843).
Författare
Summary, in English
Escolar (Lepidocybium flavobrunneum, family Gempylidae) are large and darkly coloured deep-sea predatory fish found in the cold depths (more than 200 m) during the day and in warm surface waters at night. They have large eyes and an overall low density of retinal ganglion cells that endow them with a very high optical sensitivity. Escolar have banked retinae comprising six to eight layers of rods to increase the optical path length for maximal absorption of the incoming light. Their retinae possess two main areae of higher ganglion cell density, one in the ventral retina viewing the dorsal world above (with a moderate acuity of 4.6 cycles deg(-1)), and the second in the temporal retina viewing the frontal world ahead. Electrophysiological recordings of the flicker fusion frequency (FFF) in isolated retinas indicate that escolar have slow vision, with maximal FFF at the highest light levels and temperatures (around 9 Hz at 23°C) which fall to 1-2 Hz in dim light or cooler temperatures. Our results suggest that escolar are slowly moving sit-and-wait predators. In dim, warm surface waters at night, their slow vision, moderate dorsal resolution and highly sensitive eyes may allow them to surprise prey from below that are silhouetted in the downwelling light.
Avdelning/ar
Publiceringsår
2014
Språk
Engelska
Publikation/Tidskrift/Serie
Philosophical Transactions of the Royal Society B: Biological Sciences
Volym
369
Issue
1636
Dokumenttyp
Artikel i tidskrift
Förlag
Royal Society Publishing
Ämne
- Zoology
Nyckelord
- deep-sea vision
- eye
- escolar
- visual ecology
- visual sensitivity
- visual resolution
Status
Published
Forskningsgrupp
- Lund Vision Group
ISBN/ISSN/Övrigt
- ISSN: 1471-2970