Visual pigments and oil droplets in the penguin,Spheniscus humboldti

@article{Bowmaker2004VisualPA,
  title={Visual pigments and oil droplets in the penguin,Spheniscus humboldti},
  author={James K. Bowmaker and Graham R. Martin},
  journal={Journal of Comparative Physiology A},
  year={2004},
  volume={156},
  pages={71-77}
}
SummaryThe photoreceptors of the penguin,Spheniscus humboldti, were examined using a microspectrophotometer. The cones could be divided into three classes based on their visual pigment absorbance spectra [λmax 403, 450 and 543 nm (Fig. 1)], and into five classes based on their visual pigment-oil droplet combination (Fig. 4). Oil droplets were of three types (Fig. 2). The rods contained a rhodopsin with λmax at 504 nm. No double cones were observed. The penguin should be capable of good… 
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