The Hawk-Eyed Songbird: Retinal Morphology, Eye Shape, and Visual Fields of an Aerial Insectivore

@article{Tyrrell2017TheHS,
  title={The Hawk-Eyed Songbird: Retinal Morphology, Eye Shape, and Visual Fields of an Aerial Insectivore},
  author={Luke P. Tyrrell and Esteban Fern{\'a}ndez-Juricic},
  journal={The American Naturalist},
  year={2017},
  volume={189},
  pages={709 - 717}
}
Swallows are a unique group of songbirds because they are active-pursuit predators that execute all aspects of hunting prey in flight: search, detection, pursuit, and capture. We show that swallows have evolved a visual system that is unlike that of any other studied songbird. Swallows have a bifoveate retina that provides sharp lateral and frontal vision, an unusually long eye that enhances spatial resolution, a large posterior blind area, and a narrow binocular field. We also show that… 
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