Journal of Comparative Physiology A

, Volume 163, Issue 4, pp 441–443

Crocodiles don't focus underwater

  • L. J. Fleishman
  • H. C. Howland
  • M. J. Howland
  • A. S. Rand
  • M. L. Davenport
Article

Summary

Crocodilians are amphibious reptiles which hunt prey both on land and in water. Previous refractive and anatomical studies have suggested that their eyes can focus objects in air and that their ability to refocus the eye underwater may be limited. Examination of the plane of focus of six species of crocodilians both in air and underwater has revealed that they are generally well focused in air for distant targets and severely defocused underwater. These results suggest that sensory systems other than vision must play an important role in prey capture underwater.

Abbreviation

D

diopter

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Copyright information

© Springer-Verlag 1988

Authors and Affiliations

  • L. J. Fleishman
    • 1
  • H. C. Howland
    • 2
  • M. J. Howland
    • 2
  • A. S. Rand
    • 3
  • M. L. Davenport
    • 4
  1. 1.Department of ZoologyUniversity of TexasAustinUSA
  2. 2.Division of Biological SciencesCornell UniversityIthacaUSA
  3. 3.Smithsonian Tropical Research InstituteBalboaRepublic of Panama
  4. 4.Department of HerpetologyNational Zoological ParkWashington, DCUSA

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