The really cool thing about whales is their mating song.
Males call to females, and they can hear each other across vast distances. As other males hear a song, they sing the same song, until one whale subtly alters the song in order to attract a mate by being 'different'. Sure enough, all the other males hear the change, and change their song as well, so that by the end of the mating season, the mating song is completely different from when it started, but all the males have adapted and sing the same song at the end of the season.
How cool is that?