230
Ron H. Douglas
7 Conclusions
Teleosts probably show the greatest variability of visual pigments and types of
photoreceptor of any group of vertebrates. This reflects the wide range of photic
environments that they occupy, from the almost total absence of daylight in the
deepsea to the variable coloured waters of coastal regions and freshwater lakes and
rivers. In a broad sense, there is a clear correlation between the complement of rods
and cones in any given species and its photic environment. However, we have little
understanding of the significant variations found between species in visual pigments
and photoreceptors that occur within defmed photic environments. Presumably, these
reflect differences in visual behaviour related to factors such as feeding strategies,
mating behaviour and predation. It will only be when all of the physiological,
behavioral and ecological information has been obtained and correlated that we may
begin to fully appreciate the visual ecology ofteleosts.
References
Ali MA, Harosi Fl, Wagner H-J (1978) Photoreceptors and visual pigments in a
cichlid fish, Nanna car a anomal a. Sensory Processes 2: 13 0-14 5
Archer S, Hope A, Partridge JC (1995) The molecular basis for the green-blue
sensitivity shift in the rod visual pigments of the European eel. Proc Roy Soc Lond
B 262:289-295
Archer SN, Endler JA, Lythgoe JN, Partridge JC (1987) Visual pigment
polymorphism in the guppy Poecilia reticulata. Vision Res 27:1243-1252
Archer SN, Lythgoe JN (1990) The visual pigment basis for cone polymorphism in
the guppy, Poecilia reticulata. Vision Res 30:225-233
Avery JA, Bowmaker JK, Djamgoz MBA, Downing JEG (1983) Ultraviolet sensitive
receptors in a freshwater fish. J Physiol 334:23P
Bayliss LE, Lythgoe RJ, Tansley K (1936) Some new forms of visual purple found
in deep-sea fish, with a note on the visual cells of origin. Proc Roy Soc Lond B
816:95-113
Beatty DD (1984) Visual pigments and the labile scotopic visual system of fish.
Vision Res 24:1563-1573
Beaudet L, Hawryshyn CW (1999) Ecological aspects of vertebrate visual ontogeny.
In: Archer SN, Djamdoz MBA, Loew ER, Partridge JC, Vellerga S (eds) Adaptive
Mechanisms in the Ecology of Vision. Kluwer, Dordrecht, pp 413-437
Boehlert GW (1978) Intraspecific evidence for the function of single and double
cones in the teleost retina. Science 202:309-311
Bowmaker JK ( 1984) Microspectrophotometry of vertebrate photoreceptors. A brief
review. Vision Res 24:1641-1650
Bowmaker JK ( 1990) Visual pigments of fishes. In: Douglas RH, Djamgoz MBA
(eds) The Visual System ofFish. Chapman and Hall, London, pp 81-107
Bowmaker JK ( 1991) Evolution of visual pigments and photoreceptors. In: Gregory
Ron H. Douglas
7 Conclusions
Teleosts probably show the greatest variability of visual pigments and types of
photoreceptor of any group of vertebrates. This reflects the wide range of photic
environments that they occupy, from the almost total absence of daylight in the
deepsea to the variable coloured waters of coastal regions and freshwater lakes and
rivers. In a broad sense, there is a clear correlation between the complement of rods
and cones in any given species and its photic environment. However, we have little
understanding of the significant variations found between species in visual pigments
and photoreceptors that occur within defmed photic environments. Presumably, these
reflect differences in visual behaviour related to factors such as feeding strategies,
mating behaviour and predation. It will only be when all of the physiological,
behavioral and ecological information has been obtained and correlated that we may
begin to fully appreciate the visual ecology ofteleosts.
References
Ali MA, Harosi Fl, Wagner H-J (1978) Photoreceptors and visual pigments in a
cichlid fish, Nanna car a anomal a. Sensory Processes 2: 13 0-14 5
Archer S, Hope A, Partridge JC (1995) The molecular basis for the green-blue
sensitivity shift in the rod visual pigments of the European eel. Proc Roy Soc Lond
B 262:289-295
Archer SN, Endler JA, Lythgoe JN, Partridge JC (1987) Visual pigment
polymorphism in the guppy Poecilia reticulata. Vision Res 27:1243-1252
Archer SN, Lythgoe JN (1990) The visual pigment basis for cone polymorphism in
the guppy, Poecilia reticulata. Vision Res 30:225-233
Avery JA, Bowmaker JK, Djamgoz MBA, Downing JEG (1983) Ultraviolet sensitive
receptors in a freshwater fish. J Physiol 334:23P
Bayliss LE, Lythgoe RJ, Tansley K (1936) Some new forms of visual purple found
in deep-sea fish, with a note on the visual cells of origin. Proc Roy Soc Lond B
816:95-113
Beatty DD (1984) Visual pigments and the labile scotopic visual system of fish.
Vision Res 24:1563-1573
Beaudet L, Hawryshyn CW (1999) Ecological aspects of vertebrate visual ontogeny.
In: Archer SN, Djamdoz MBA, Loew ER, Partridge JC, Vellerga S (eds) Adaptive
Mechanisms in the Ecology of Vision. Kluwer, Dordrecht, pp 413-437
Boehlert GW (1978) Intraspecific evidence for the function of single and double
cones in the teleost retina. Science 202:309-311
Bowmaker JK ( 1984) Microspectrophotometry of vertebrate photoreceptors. A brief
review. Vision Res 24:1641-1650
Bowmaker JK ( 1990) Visual pigments of fishes. In: Douglas RH, Djamgoz MBA
(eds) The Visual System ofFish. Chapman and Hall, London, pp 81-107
Bowmaker JK ( 1991) Evolution of visual pigments and photoreceptors. In: Gregory