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Visual pigments and oil droplets from six classes of photoreceptor in the retinas of birds
Microspectrophotometric examination of the retinal photoreceptors of the budgerigar (shell parakeet), Melopsittacus undulatus (Psittaciformes) and the zebra finch, Taeniopygia guttataExpand
Evolution of vertebrate visual pigments
  • J. Bowmaker
  • Biology, Medicine
  • Vision Research
  • 1 September 2008
The visual pigments of vertebrates evolved about 500 million years ago, before the major evolutionary step of the development of jaws. Four spectrally distinct classes of cone opsin evolved throughExpand
Evolution of vertebrate visual pigments
Most New World species exhibit a trichromacy that is based on only two opsin genes, an autosomal SWS1 gene as in Old World primates, and a polymorphic X-linked LWS gene with multiple allelic forms that encode pigments with differing λmax values lying between about 535 and 565 nm. Expand
Visual pigments of rods and cones in a human retina.
If assumptions are made about the length of cones and about pre‐receptoral absorption, it is possible to derive psychophysical sensitivities for the cones that closely resemble the appropriate pi mechanisms of W. S. Stiles, however, the psychophysical sensitivity derived for the rods is considerably broader than the C.I.E. scotopic sensitivity function. Expand
Evolution of the cichlid visual palette through ontogenetic subfunctionalization of the opsin gene arrays.
Subfunctionalization through differential ontogenetic expression may be a key mechanism for preservation of opsin genes and provide a palette from which selection creates the diverse visual sensitivities found among the cichlid species of the lacustrine adaptive radiations. Expand
Mix and Match Color Vision: Tuning Spectral Sensitivity by Differential Opsin Gene Expression in Lake Malawi Cichlids
This work established the cone complements of four species of Malawi cichlids by combining microspectrophotometry of isolated cones, sequencing of opsin genes, and spectral analysis of recombinant pigments, which suggested that all percomorph fish have similar potential. Expand
Human visual pigments: microspectrophotometric results from the eyes of seven persons
Both patients were classified as normal trichromats by all clinical tests of colour vision but there was a clear difference in their relative sensitivities to long-wave fields, which proved to be that required by the microspectrophotometric results. Expand
Spectral tuning of avian violet- and ultraviolet-sensitive visual pigments.
This paper presents the sequences of two pigments isolated from Humbolt penguin and pigeon with intermediate lambda(max) values of 403 and 409 nm, respectively and identifies five amino acid sites that show a pattern of substitution between species that is consistent with differences inlambda(max). Expand
Colour vision in the passeriform bird, Leiothrix lutea: correlation of visual pigment absorbance and oil droplet transmission with spectral sensitivity
Comparison of these results with the behavioural spectral sensitivity function of Leiothrix lutea suggests that the increment threshold photopic spectral sensitivity of this avian species is mediated by the 4 single cone classes modified by neural opponent mechanisms. Expand
Variations of colour vision in a New World primate can be explained by polymorphism of retinal photopigments
Good quantitative agreement was found when the microspectrophoto-metrically measured absorbance spectra were used to predict the behavioural sensitivity of individual animals to long wavelengths and suggests that the behavioural variation arises from variation in the retinal photopigments. Expand