Vision: Shortcomings of an eagle's eye

  title={Vision: Shortcomings of an eagle's eye},
  author={Graham R. Martin},
Lead exposure and food processing in white-tailed eagles and other scavengers: an experimental approach to simulate lead uptake at shot mammalian carcasses
Findings indicate that the use of bullets that deform or fragment into particles greater than 9 mm in size, such as numerous lead-free bullets, may prevent metal ingestion and poisoning in avian scavengers.
Sensory basis of vigilance behavior in birds: Synthesis and future prospects
ensory basis of vigilance behavior in birds : Synthesis and future prospects
The goal of this study was to review some visual properties involved in scanning behavior (retinal specialization for visual resolution and motion detection, visual acuity, and size of the blind area), and hypothesize how the inter-specific variability in these properties may lead to different scanning strategies.
Hawk Eyes II: Diurnal Raptors Differ in Head Movement Strategies When Scanning from Perches
Cooper's Hawks, Red-tailed Hawks, and American Kestrels have species-specific strategies to gather visual information while perching that may optimize prey search and detection with different visual systems in habitat types with different degrees of visual obstruction.
Avian visual system configuration and behavioural response to object approach
Visual insignificance of the foveal pit: reassessment of foveal hypoplasia as fovea plana.
It is shown that a foveal pit is not required for foveAL cone specialization, anatomically or functionally, and this helps to explain the potential for good acuity in the absence of a pit and raises questions about the visual role of the fovea plana.
Avian vision: a review of form and function with special consideration to birds of prey
How birds, particularly birds of prey, see is understood by reviewing pertinent anatomy and physiology of the eye, color vision, visual fields, visual acuity, accommodation, and flicker-fusion frequency.
The visual acuity and refractive state of the American kestrel (Falco sparverius)
Tests of hypotheses on predation as a factor maintaining polymorphic melanism in coastal‐plain fox squirrels (Sciurus niger L.)
Results indicated that morphs of coastal-plain fox squirrels with all-light backs are better static matches to unburned backgrounds than are the darker morphs with which they coexist, and this result suggests a possible factor that would favour retention of genes for dorsal blackness in the coastal- Plain population.


Falcon visual sensitivity to grating contrast
It is reported that the cut-off frequency (a measure of visual acuity) is twice the expected value and is the same for kestrel and human eyes.
Form and Function in Birds
This classic work forms a complete reference to avian anatomy, with a particular focus on the ways in which structure relates to biology and function. An international team of expert authors each
The Ferrier lecture, 1980
  • H. Barlow
  • Biology
    Proceedings of the Royal Society of London. Series B. Biological Sciences
  • 1981
Three stages of dealing with the visual image are proposed: the improvement of the cortical map in primary visual cortex by processes analogous to spatial and temporal interpolation ; the detection of linking features in this map; and the concentration of this information by non-topographical mapping in adjacent visual areas.
Vertebrate photoreceptor optics
A comparison of Vertebrate and Invertebrate Photoreceptors and aoretical Consideration of Optical Interactions in an Array of Retinal Receptors is presented.