This reminds me of some research done by an Australian group, who were trying to figure out why the crows kept getting run over on the highway. It seemed strange for such intelligent birds. What they noted through hours of observation was that the crows were always run over by trucks and not cars. Careful observation revealed that it was always the duty of one crow to go on the lookout, and if a car approached, it would warn the others and they would take flight. They realised was that the crows perished because they had a limited vocabulary. They can say "Kaaar" ...... but not truck. Cody would love this one