I have written about learning by observation several times, beginning with Lads Before the Wind in 1975 (reissued with four new chapters in 2000), and the account of two Steno bredanensis, or rough-toothed dolphins, that were inadvertently switched during shows and succeeded in doing most of each other's repertoires, including some shaped behaviors. One animal accepted blindfolds and located and retrieved sinking hoops, a behavior that had taken weeks to train in the model animal. The other animal succeeded in jumping through a hoop high above the water. (They had separate show routines, but could watch each other, day after day, from the holding tanks which had barred underwater gates. Probably sitting there saying "Heck, I could do that!")
I'm very interested in the question of dogs learning by observation. The 'decisive' paper that proved that dogs don't learn by observation was a very limited study, I believe, involving two dogs with no particular reinforcement history, in which the observer dog failed to learn some task... And somehow it went into the zeitgeist as a firm conclusion, one I was totally prepared to believe in myself, at one time. I thought that dolphins do learn by observation, and dogs don't. Then I started giving seminars, and seeing all kinds of observational learning going on.
"Tell me this," said the Old Falconer, rocking back on his heels a little. "I want my bird to come back to me when she's too far away; but I want her to come back AND to stay up in the air. If I give her your click signal for coming back, she's got to come down to me to get her reward, right? So how can I do that and still get her to stay overhead?" And he glared at me with "Gotcha!" in his eyes.