Multifocal lenses in coral reef fishes

Research output: Contribution to journalArticle


The optical properties of crystalline lenses were studied in eleven species of coral reef fish from the Red Sea in Eilat, Israel. Three species each of diurnal planktivores, nocturnal planktivores and diurnal herbivores constituted three groups of animals with little within-group variability. In addition we studied two predators, which differed with respect to body size, prey preference, hunting method and diel activity period. All species studied have multifocal lenses. There were statistically significant differences in the optical properties of the lenses between the first three groups and between the predatory species. The properties of the lenses correlate well with known complements of visual pigments and feeding habits. Lenticular zones focusing ultraviolet light were found in two diurnal planktivores. The optical properties of the lens seem to be specifically adapted to the visual needs of each species.


  • Björn Karpestam
  • Jonas Gustafsson
  • Nadav Shashar
  • Gadi Katzir
  • Ronald Kröger
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Zoology


  • Red Sea, spherical aberration, chromatic aberration, physiological optics, color vision, visual pigments
Original languageEnglish
Pages (from-to)2923-2931
JournalJournal of Experimental Biology
Issue number16
Publication statusPublished - 2007
Publication categoryResearch