Visual Fields in Short-Toed Eagles, Circaetus gallicus (Accipitridae), and the Function of Binocularity in Birds

@article{Martin1999VisualFI,
  title={Visual Fields in Short-Toed Eagles, Circaetus gallicus (Accipitridae), and the Function of Binocularity in Birds},
  author={Graham R. Martin and Gadi Katzir},
  journal={Brain, Behavior and Evolution},
  year={1999},
  volume={53},
  pages={55 - 66}
}
Visual fields were determined in alert restrained birds using an ophthalmoscopic reflex technique. The region of binocular overlap is relatively small: maximum width of 20° occurs approximately 15° below the horizontal, and the field extends vertically through 80° with the bill tip placed close to the centre. Monocular field width in the horizontal plane is 139°, and the field is asymmetric about the optic axis. The cyclopean field extends through 260°, and the blind area above and behind the… 

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