I realize you can just answer, “mysterious aliens beyond our understanding,” but why would a space probe have a mandate of either talk to a whale for 30 seconds or destroy Earth and disable everything in its path on the way to Earth?
Why? What does that achieve?
Back in the 80s everyone thought that whale was going to be the hottest new actor in Hollywood. They were all trying to sign him, for a second it was thought he would be playing opposite Tom Cruise in Top Gun.