Musical appreciation is almost shockingly absent from animals.

One possible reason is that allowing one’s nervous system to be entrained to external rhythms is potentially exploitable. So humans may have evolved the ability to “let the guard down.”

This is pretty fascinating, do you have anything else to say about it? Makes me think of mesmerism and snake-charmers, although IDK how real that is.

Another thing that comes to mind is recent pop-sci talking about how individual bees can measure time pretty accurately, which I personally found very surprising, even though I've heard that they "dance" for communication.

Rhythm appreciation is neurologically very interesting since it requires several basic abilities acting at once, including tracking time, but also a certain amount of memory and pattern recognition. Animal appreciation of melodic stuff and harmony is interesting too but seems much harder to study and more dependent on physical aspects of ears

You know the old quote about how music hath charms to soothe a savage beast? That turns out to be a misquote. It's actually

  Music hath charms to soothe a savage breast,
  To soften rocks, or bend a knotted oak.”