T W Cronin

..Ten amino acid sites relating to these properties were found to face the binding pocket, within 4 A of the chromophore and thus have the potential to affect spectral tuning...

..Although circularly polarized light is rare in nature, it is produced by the surfaces of some animals, where it may be used in specialized systems of communication...

..Gannets are large seabirds that hunt fish from the air, making a plunge dive followed by active swimming pursuit of prey. A recent study shows that they convert from aerial to aquatic vision nearly instantly...

..Phylogenetic analysis of opsin relatedness suggests that opsins specialized for colour vision have diverged from those devoted to polarization vision, and possibly motion and spatial vision...

..Ph. versicolor, on the other hand, appears to have a visual system that offers a compromise between maximum sensitivity to, and maximum discrimination of, their signals...

..Plasticity in retinal spectral function may be common in mantis shrimp species that occupy a range of habitat depths...

..Vision in these species, therefore, is not tuned to spectral characteristics of the photic environment by varying the assemblages of visual pigments appearing in their retinas...

..Also, the relative spectral constancy of the angle and degree of polarization supports fish polarization sensitivity, which relies on spectrally diverse photoreceptor sets...

..The spectral sensitivity of specific classes of photoreceptor is adjusted by filters that vary between individuals...

..Many of these unusual features of mantis shrimp vision may inspire new sensor designs for machine vision...

..The quality of the visual worlds experienced by each species we studied must vary considerably, but all appear to exploit the full capabilities offered by their complex visual systems...

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..These results demonstrate that cuttlefish and squid could send out reliable polarization signals to a receiver regardless of arm orientation...

..These two clusters of sites indicate that stomatopod opsins have diverged with respect to both spectral tuning and signal transduction...

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..Using these quantitative methods to score and reconstruct color changes among closely related taxa provides a better understanding of how elaborate animal colors evolve...

..The major controlling element of the plasticity in lysiosquilloid stomatopod color vision appears to be light intensity rather than spectral distribution...

..The use of digital video data in spectral analysis provides a promising new approach to the studies of the spatial and temporal variation of illumination in natural scenes and the understanding of color vision in natural environments...

..g. midband Rows 2 and 3) enhances the contrast of certain color signals to a large enough degree to make co-evolution between color vision and these rather specific color signals likely...

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..These results suggest that meral spot coloration may have evolved as a constant signal when viewed by conspecifics from various depths...

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..Our results indicate that the colors displayed by the various color morphs of D. pumilio are effective signals both to conspecifics and to a model predator...

..However, in two species, females had colours that were more conspicuous than male colours, suggesting that other selective forces and possibly sexual conflicts are acting in this system...

..As hydrothermal vents produce light, vision may supplement thermal and chemical senses to orient postlarval settlement at vent sites...

..700 nm. The deviations from visual-pigment spectra can be explained by ocular light filters based on three types of identified screening pigments...

..The potential utility of polarized iridescence and iridescent wing coloration within differing ambient spectral environments is discussed to provide a basis for future investigation of the polarized light ecology of butterflies...

..We hypothesize that sensitivity to longer wavelengths enhances contrast between background (blue sky or tall vegetation) and the male major claw during the waving display...

..Intracellular recordings within the dorsal rim area show very high polarisation sensitivity and a sensitivity peak within the ultraviolet part of the spectrum...

..respond most to blue light (440 nm), and have a smaller, secondary response peak to orange-red light (600 nm). These data suggest that the photoreceptive pigment in sponge larvae may be a flavin or carotenoid...

..Navigation and body orientation based on the celestial polarization pattern are predicted to be limited to shallow waters as well, while navigation based on the solar position is possible through a deeper range...