Of what?
Robins are born with brains wired to sing like robins. More importantly,
robins are wired to respond to robin songs. There are many parts of this
song that are 'set', and then there are parts where variation is allowed.
Within this part of the song, some variables might be a result of mutation
and heredity. Other variables are undoubtedly the result of the the songs
heard as a chick. I think it is unlikely that a robin can be trained to
sing like a chickadee. Doing so would reduce it's chances of mating to
virtually zero, so not only is it unlikely to be possible, there might even
be mechanisms in place to prevent it from happening.
corey
ps I think that adopted birds mimicking their adopted parents is an
excellent example of a meme. It doesn't much resemble the common example of
memes, but it fits the definition perfectly.