The bird thing is a coincidence. I'm not sure of the interval, but it's chickadees in spring that do the pronounced two note whistle, and I wrote it into a song, available on my MIDI page (called Birdsong), and now whenever I go out and hear the birds sing, that tune starts in my head.
http://home.earthlink.net/~sondahl/birdsong.mid
there's the blue clicky to it.