From The Hitchhiker's Guide to the Galaxy by Douglas Adams

"It is an important and popular fact that things are not always what they seem . . . On the planet Earth, man had always assumed that he was more intelligent than the dolphins because he had achieved so much . . . the wheel, New York, wars . . . while all the dolphins had ever done was muck about in the water having a good time . . . Curiously enough, the dolphins had long known of the impending destruction of . . . Earth, and had made many attempts to alert mankind . . . but most of their communications were misinterpreted as amusing attempts to punch footballs or whistle for tidbits, so they eventually gave up and left the Earth by their own means . . . The last ever dolphin message was misinterpreted as a surprisingly sophisticated attempt to do a double-backward somersault through a hoop while whistling the 'Star-Spangled Banner,' but in fact the message was this: So long and thanks for all the fish."