Last night on my drive home, I missed the turnoff for 691 and only realized it when I hit I-95. On my long and convoluted trip home along route 34, I listened to a very interesting segment on NPR. It discussed the intelligence of birds, and how it closely approaches the intelligence of apes.
The story calls crows and jays "the Einsteins of the avian world", and replays the recorded results of one experiment in which a woman tests a parrot, showing it two keys.
"How many are there? How many?"
"Two!"
"And what's different about them?"
"Color!"
"Which color bigger?"
"Shape!"
"Which color bigger?"
"Green!"
For a bird, that's pretty amazing.
http://www.pbs.org/saf/1201/video/watchonline.htm