Leuckart's law

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Leuckart's law is an empirical law in zoology that states that the size of the eye of an animal is related to its maximum speed of movement; fast-moving animals have larger eyes, after allowing for the effects of body mass. The hypothesis dates from 1876, [1] and in older literature is usually referred to as Leuckart's ratio. [2] It was proposed by Rudolf Leuckart in 1876. [3]

Contents

The principle was initially applied to birds; it has also been applied to mammals. [4]

Criticism

A study of 88 bird species, published in 2011, found no useful correlation between flight speed and eye size. [5]

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References

  1. Hugh Davson, Lewis Texada Graham (1974). The Eye: Comparative physiology, Volume 2. New York: Academic Press. p. 274.
  2. Stewart Duke-Elder (1958). System of Ophthalmology: The eye in evolution, Volume 1 of System of Ophthalmology. London: Henry Kimpton. p. 401.
  3. Leuckart, R. (1876). "Organologie des Auges. Vergleichende Anatomie". In Graefe, Alfred; Saemisch, Theodor (eds.). Handbuch der gesamten Augenheilkunde. Leipzig: Engelmann. pp. 145–301.
  4. A.N. Heard-Booth, E.C. Kirk (2012). The influence of maximum running speed on eye size: a test of Leuckart's Law in mammals. Anatomical Record295 (6): 1053-1062. doi: 10.1002/ar.22480 PMID   22539450.
  5. M.I. Hall, C.P. Heesy (2011). Eye size, flight speed and Leuckart's Law in birds. Journal of Zoology283: 291–297. doi:10.1111/j.1469-7998.2010.00771.x