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Proc Biol Sci. Jun 22, 2003; 270(1521): 1255–1261.
PMCID: PMC1691374

Coloured oil droplets enhance colour discrimination.

Abstract

The eyes of most diurnal reptiles and birds contain coloured retinal filters-oil droplets. Although these filters are widespread, their adaptive advantage remains uncertain. To understand why coloured oil droplets appeared and were retained during evolution, I consider both the benefits and the costs of light filtering in the retina. Oil droplets decrease cone quantum catch and reduce the overlap in sensitivity between spectrally adjacent cones. The reduction of spectral overlap increases the volume occupied by object colours in a cone space, whereas the decrease in quantum catch increases noise, and thus reduces the discriminability of similar colours. The trade-off between these two effects determines the total benefit of oil droplets. Calculations show that coloured oil droplets increase the number of object colours that can be discriminated, and thus are beneficial for colour vision.

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Selected References

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  • Arnold K, Neumeyer C. Wavelength discrimination in the turtle Pseudemys scripta elegans. Vision Res. 1987;27(9):1501–1511. [PubMed]
  • Barlow HB. What causes trichromacy? A theoretical analysis using comb-filtered spectra. Vision Res. 1982;22(6):635–643. [PubMed]
  • Bowmaker JK, Knowles A. The visual pigments and oil droplets of the chicken retina. Vision Res. 1977;17(7):755–764. [PubMed]
  • Bowmaker JK, Heath LA, Wilkie SE, Hunt DM. Visual pigments and oil droplets from six classes of photoreceptor in the retinas of birds. Vision Res. 1997 Aug;37(16):2183–2194. [PubMed]
  • Govardovskii VI. On the role of oil drops in colour vision. Vision Res. 1983;23(12):1739–1740. [PubMed]
  • Govardovskii VI, Zueva LV. Visual pigments of chicken and pigeon. Vision Res. 1977;17(4):537–543. [PubMed]
  • Govardovskii VI, Fyhrquist N, Reuter T, Kuzmin DG, Donner K. In search of the visual pigment template. Vis Neurosci. 2000 Jul-Aug;17(4):509–528. [PubMed]
  • Hart NS. The visual ecology of avian photoreceptors. Prog Retin Eye Res. 2001 Sep;20(5):675–703. [PubMed]
  • Hart Nathan S. Vision in the peafowl (Aves: Pavo cristatus). J Exp Biol. 2002 Dec;205(Pt 24):3925–3935. [PubMed]
  • Hart NS, Partridge JC, Cuthill IC, Bennett AT. Visual pigments, oil droplets, ocular media and cone photoreceptor distribution in two species of passerine bird: the blue tit (Parus caeruleus L.) and the blackbird (Turdus merula L.). J Comp Physiol A. 2000 Apr;186(4):375–387. [PubMed]
  • Jarvis John R, Taylor Nina R, Prescott Neville B, Meeks Ian, Wathes Christopher M. Measuring and modelling the photopic flicker sensitivity of the chicken (Gallus g. domesticus). Vision Res. 2002 Jan;42(1):99–106. [PubMed]
  • King-Smith PE. Absorption spectra and function of the coloured oil drops in the pigeon retina. Vision Res. 1969 Nov;9(11):1391–1399. [PubMed]
  • Loew ER, Govardovskii VI. Photoreceptors and visual pigments in the red-eared turtle, Trachemys scripta elegans. Vis Neurosci. 2001 Sep-Oct;18(5):753–757. [PubMed]
  • Provencio I, Loew ER, Foster RG. Vitamin A2-based visual pigments in fully terrestrial vertebrates. Vision Res. 1992 Dec;32(12):2201–2208. [PubMed]
  • Hari R, Salmellin R, Tissari SO, Kajola M, Virsu V. Visual stability during eyeblinks. Nature. 1994 Jan 13;367(6459):121–122. [PubMed]
  • Vorobyev M, Osorio D. Receptor noise as a determinant of colour thresholds. Proc Biol Sci. 1998 Mar 7;265(1394):351–358. [PMC free article] [PubMed]
  • Vorobyev M, Osorio D, Bennett AT, Marshall NJ, Cuthill IC. Tetrachromacy, oil droplets and bird plumage colours. J Comp Physiol A. 1998 Nov;183(5):621–633. [PubMed]
  • Vorobyev M, Brandt R, Peitsch D, Laughlin SB, Menzel R. Colour thresholds and receptor noise: behaviour and physiology compared. Vision Res. 2001 Mar;41(5):639–653. [PubMed]

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