Having traveled around the nation and the world I have noticed that birds in certain regions tend to know similar songs or birdcalls. In fact birds of different species seem to know many of the same sounds and calls. This would lead one to surmise that the birds are communicating with other birds, which are of a totally different breed. But the story does not stop there. Recently I was in an industrial area near a wildlife area and the birds had picked up sounds of forklifts backing up;