Vision of the Humboldt penguin (Spheniscus humboldti) in air and water

  title={Vision of the Humboldt penguin (Spheniscus humboldti) in air and water},
  author={J. G. Sivak and Howard C. Howland and Patricia McGill-Harelstad},
  journal={Proceedings of the Royal Society of London. Series B. Biological Sciences},
  pages={467 - 472}
Refractive states measured by retinoscopy and photorefraction indicate that the eyes of the Humboldt penguin, Spheniscus humboldti, are approximately emmetropic in air and water. Extensive myopia in air, as predicted by earlier authors and by a recent anatomical study, is non-existent. Photorefractive measurements of the refractive state, in water, of the Humboldt penguin indicate that it can accommodate sufficiently to make up the loss of the refractive power of the cornea. The cornea of the… 

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Penguin vision in air and water