My friend Kevin just pointed me at this YouTube video, which shows a dog grooving to some guitar music.
The dog is definitely appreciating the music (and Kevin was particularly interested in the fact that he smiles while the music is playing). I, on the other hand, am curious about the fact that the dog seems to actually be moving his head in time to the music. This could just be coincidence, and the human tendency to anthropomorphize. Or the dog could be reacting to motions of the guarist off-screen. Or it could be real.
I have never seen a dog demonstrate an understanding of musical rhythm before (though I saw a parrot do so on another YouTube video). Of course dogs will howl along, but feeling the beat is something different. I can’t remember ever seeing a journal article about the rhythmic abilities of canids!