Birds that feed-on-the-wing have few isthmo-optic neurons.

@article{Feyerabend1994BirdsTF,
  title={Birds that feed-on-the-wing have few isthmo-optic neurons.},
  author={B Feyerabend and Cordula Renate Malz and Dietrich L. Meyer},
  journal={Neuroscience letters},
  year={1994},
  volume={182 1},
  pages={66-8}
}
The isthmo-optic system is less developed in birds feeding-on-the-wing, than in pecking avians. This was suggested previously. By intraocular horseradish peroxidase applications, we studied the central origin of this retino-petal system in thrush, haw finch, swift and swallow. Our data support the assumption on a correlation between feeding habits and the development of the isthmo-optic nucleus in adult avians as this brainstem region is more highly developed in thrush and finch than in swift… CONTINUE READING