Spatial visual acuity of the falcon, Falco berigora: A behavioural, optical and anatomical investigation

doi:10.1016/0042-6989(87)90114-3

Vision Research

Volume 27, Issue 10, 1987, Pages 1859-1874

https://doi.org/10.1016/0042-6989(87)90114-3 Get rights and content

Abstract

In the brown falcon the relationship between acuity, as measured using a task designed to test minimum-separable acuity, and luminance was investigated as well as the possible determinants of that relationship. The maximum acuity was 73 c/deg and was found to be resistant to decreases in luminance. Maximum behavioural acuity corresponds closely with the maximum anatomical resolving power of the eye, though it is postulated that, in the first instance, acuity is optically constrained. The flat acuity-luminance function of the falcon results from adaptations which increase the optical sensitivity of the eye compared with the globose eye of strongly diurnal falconiformes.

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Vision Research

Abstract

Reference (23)

Near-field visual acuity of pigeons: effects of scotopic adaptation and wavelength

Vision Res.

Averaging over the foveal receptor aperture curtails aliasing

Vision Res.

Spatial visual acuity of the eagle, Aquila audax: a behavioural, optical and anatomical investigation

Vision Res.

Information capacity of eyes

Vision Res.

Eagles, Hawks and Falcons of the World

Monocular versus binocular visual acuity

Nature, Lond.

A Fiji peregrine (Falco peregrinus) in an urban-marine environment

Notoris

The visual acuity of some passerine birds

Acta zool. fennica

Factors underlying falcon grating acuity

Nature, Lond.

A comparative study of deep avian foveas

Brain Behav. Evol.

Falcon visual acuity

Science, N.Y.

Cited by (89)

Retinal ganglion cell distribution and spatial resolution in the Asiatic toad Bufo gargarizans (Günther, 1859)

Avian vision

The Fovea: Structure, Function, Development, and Tractional Disorders

Visual adaptations of diurnal and nocturnal raptors

The buzz around spatial resolving power and contrast sensitivity in the honeybee, Apis mellifera

Bird collisions with power lines: State of the art and priority areas for research