OH, I don't if you've come across this yet but Sperm whales sing their songs, they have different songs. They travel the ocean and have their own places. The songs change slightly over the years but what has been documented is when a Sperm whale crosses whatever boarder they cross under the sea they switch songs AND they switch to the song for that sea AND they switch to the point that they stopped at when they went the other way.
And they turn around and do it again the other way though most of the paths are more circular.
They are communicating, they do have a language, we just don't understand it. It changes so is that creation of a new idea into the song or is it a propagation of someones error into the song. They don't know yet.
Douglass Adams quote
"It's an important and popular fact that things are not always what they seem. For instance, on the planet Earth, man had always assumed that he was the most intelligent species occupying the planet, instead of the third most intelligent. The second most intelligent creatures, were of course dolphins who, curiously enough, had long known of the impending destruction of the planet Earth. They had made many attempts to alert mankind to the danger, but most of their communications were misinterpreted as amusing attempts to punch footballs or whistle for titbits. So they eventually decided they would leave Earth by their own means. The last ever dolphin message was misinterpreted as a surprisingly sophisticated attempt to do a double-backwards somersault through a hoop while whistling "the Star-Spangled Banner", but in fact, the message was this: [dolphin freeze-frames in mid-air] "So long, and thanks for all the fish!""
"It was assumed that men were smarter because of all the improvements to life, creation of finance, automobiles, digital watches that they had made while all the dolphins ever did was swim around all day, eat fish and make more little dolphins. The Dolphins meanwhile assumed they were smarter for exactly the same reasons."
I can't remember which of the hitchhikers guide series the second part was from.