While I agree it is worthwile to seek those answers, I don't feel there is anything wrong with not knowing the answer to many of those big mysteries.
It sounds like we just disagree with the definition of music. Someone can play Mary had a little lamb on their phone (which is music), but I don't see what complex abstract idea that is trying to get across. The main idea of the article is that some animals make sounds which match the patterns of human music that don't seem to serve any utilitarian purpose.