Retinal specializations in the blue marlin: eyes designed for sensitivity to low light levels
Författare
Summary, in English
The large eyes and well-developed visual system of billfishes suggest that vision is an important sense for the detection and interception of prey and lures. Investigations of visual abilities in these large pelagic fishes are difficult, however anatomical studies of billfish eyes and retinas allow prediction of a number of visual capabilities. From the density of ganglion cells in the blue marlin (Makaira nigricans) retina, visual acuities of less than 10 cycles per degree were derived, a surprisingly low visual resolution given the absolute size of the marlin eye. Cone photoreceptors, on the other hand, were present in high densities, resulting in a presumed summation of cones to ganglion cells at a ratio of 40:1, even in the area of best vision. The optical sensitivity of the marlin eye was high owing to the large dimensions of the cone photoreceptors. These results indicate that the marlin eye is specifically adapted to cope with the low light levels encountered during diving. Since the marlin is likely to use its vision at depth, it is suggested that this line of research could help estimate the limits of vertical distribution based on light level.
Avdelning/ar
Publiceringsår
2003
Språk
Engelska
Sidor
333-341
Publikation/Tidskrift/Serie
Marine and Freshwater Research
Volym
54
Issue
4
Dokumenttyp
Artikel i tidskrift
Förlag
CSIRO Publishing
Ämne
- Zoology
Nyckelord
- retinal anatomy
- acuity
- billfish
- optical sensitivity
Status
Published
Forskningsgrupp
- Lund Vision Group
ISBN/ISSN/Övrigt
- ISSN: 1448-6059