Songs by Animals?

I'd rather not decide that humans are "above" the "animals" just because some book says so. I've spent a lot of time thinking through what makes us truly different and if it would be possible for some other branch of species to evolve into having the rational capabilities that humans have.

The one thing that I'd expect an animal to have is the ability to put together a structured song. One that can be learned and passed down. A simple warble doesn't cut it. Do animals have that ability? Where is the evidence?