Bird vision

[Carl Clifford <>]

Dear All,

The vision of birds is quite different to that of humans. Not only do  
they have 4 types of cone cells in the retina, instead of our 3, avian  
cone cells contain oil droplets which act as filters. It is near  
impossible for humans to imagine what bird perceive visually. I think  
discussing how light effects birds is rather like debating how many  
Angels can dance on on the head of a pin.
There is an excellent article from Scientific American, entitled "What  
Birds See" downloadable at  http://www.csulb.edu/labs/bcl/elab/avian  
vision_intro.pdf

Cheers,

Carl Clifford
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www.birding-aus.org
birding-aus.blogspot.com

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