Photoreceptor types, visual pigments, and topographic specializations in the retinas of hydrophiid sea snakes

  title={Photoreceptor types, visual pigments, and topographic specializations in the retinas of hydrophiid sea snakes},
  author={Nathan S. Hart and Jo{\~a}o Paulo Coimbra and Shaun P. Collin and Guido Westhoff},
  journal={Journal of Comparative Neurology},
Sea snakes have evolved numerous anatomical, physiological, and behavioral adaptations to suit their wholly aquatic lifestyle. However, although sea snakes use vision for foraging and mate selection, little is known about their visual abilities. We used microspectrophotometry, light microscopy, and scanning electron microscopy to characterize the retinal photoreceptors of spine‐bellied (Lapemis curtus) and horned (Acalyptophis peronii) sea snakes. Both species have three types of visual pigment… 

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Rod-like Properties of Small Single Cones: Transmutated Photoreceptors of Garter Snakes (Thamnophis proximus)

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The photoreceptors of Boa constrictor, a boid snake of the subfamily Boinae, were examined with scanning electron microscopy and microspectrophotometry and the data indicate that wavelength discrimination above 430 nm would not be possible without some input from the rods.

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It is shown that, while the spectral tuning of the rod and cone pigments of sharks varies between species, each shark has only a single long-wavelength-sensitive cone type, suggesting that sharks may be cone monochromats and, therefore, potentially colour blind.

Microspectrophotometry of visual pigments and oil droplets in a marine bird, the wedge-tailed shearwater Puffinus pacificus: topographic variations in photoreceptor spectral characteristics

  • N. Hart
  • Biology
    Journal of Experimental Biology
  • 2004
It is proposed that the reduction in cone oil droplet pigmentation in retinal areas associated with high visual acuity is an adaptation to compensate for the reduced photon capture ability of the narrower photoreceptors found there.

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