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, and in older literature is usually referred to as Leuckart's ratio. It was proposed by Rudolf Leuckart in 1876.
The principle was initially applied to birds; it has also been applied to mammals.
Criticism A study of 88 bird species, published in 2011, found no useful correlation between flight speed and eye size.
References M.I. Hall, C.P. Heesy (2011). Eye size, flight speed and Leuckart's Law in birds. Journal of Zoology 283: 291–297.
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 Record 295 (6): 1053-1062. doi: 10.1002/ar.22480 .
Hugh Davson, Lewis Texada Graham (1974). The Eye: Comparative physiology, Volume 2. New York: Academic Press. p. 274.
Stewart Duke-Elder (1958). System of Ophthalmology: The eye in evolution, Volume 1 of System of Ophthalmology. London: Henry Kimpton. p. 401.