SEEING EYE DOGS
'(<a href="http://www.j-archive.com/media/2007-12-26_DJ_19.jpg" target="_blank">Jon of the Clue Crew crosses the street with a trainer & her dog at The Seeing Eye in New Jersey.</a>)  A Seeing Eye dog owner listens to traffic to know when to say "forward"; the dog doesn't know when to go because dogs have this visual deficiency of their own'
colorblindness