Licht-im-Terrarium: Literaturdatenbank
Licht-im-Terrarium: Literaturdatenbank |
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Goldsmith, T. H. (1990). Optimization, constraint, and history in the evolution of eyes. The Quarterly Review of Biology, 65(3), 281–322. Added by: Sarina (2008-12-16 20:27:07) |
| Resource type: Journal Article BibTeX citation key: Goldsmith1990 View all bibliographic details  |
Categories: Englisch = English Keywords: Sehvermögen = Visual Perception Creators: Goldsmith Collection: The Quarterly Review of Biology |
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| Abstract |
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Several features of the evolution of eyes and photoreceptors are examined in an effort to explore the relative roles of adaptation and historical and developmental constraints. Optical design shows clear evidence of adaptation, which is some respects approaches optima predictable from physics. The primate fovea, on the other hand, illustrates how adaptation can be channeled by developmental heritage. The primary structure of opsins reveal multiple evolutionary lineages within both Drosophila and humans. The pigments of vertebrate rods comprise a subset of opsins whose evolutionary relationships map onto the phylogeny of the parent species. The evolutionary reasons for why most rod pigments absord maximally at 500 ± 10 nm are obscure, as there is no convincing explanation based on adaptation alone. Rods are appropriately distinguished from cones on the basis of which opsin gene is expressed. This criterion is likely to be in conflict with other difinitions in phyletic lines (e.g., geckos, snakes) that have long diurnal of noctural histories accompanied by loss of one or more opsin genes, followed by a secondary adaptation to life in a different photic environment. Color vision-a generalizable perception associated with the spectral composition of light-is usefully distinguished from wavelength-specific behaviors. The latter are also based on multiple visual pigments and more that one spectral class of receptors but cannot be altered by learning. The distinction is particularly forceful in bees, which exhibit both kinds of behavior. The evolution of primate color vision has been shaped by historical factors involving an extensive period of early mammalian nocturnality. Birds, by contrast, have more elaborate cones and a richer set of visual pigments. Avian color space can be represented in a tetrahedron.
Added by: Sarina |