> Crows are somewhat unique as an animal in that they've got the ability to pass information off to other members of the flock, and to continue passing information down through generations as necessary.

Not that unique. My grandfather was a forester, his favourite time passing was to whistle back bird's song, changing only a little bit at a time, turning it slowly into something totally different. The changed song was passed to other birds and offsprings no probs.

The result was quite hilarious, you went to the primeval woods and you could hear wild birds singing the Für Elise... I bet it freaked out ornithologists!

(My granddad died about 30 years ago, sadly the bird "dialect" has vanished since, but I still have some old tapes in the attic.)

Please digitize and post some of these recordings!

This is an absolutely beautiful story! My mother always whistles back at the birds, but mostly just tries to imitate their songs. But she used to play "Für Elise" on the piano when I was a child :)