There are no lyrics to this tune, but the title is a way to remember the rhythm of the melody.
The tune is related to so many other fiddle tunes: Polly Wolly Doodle, Eico Eico, Ain't No Bugs on Me, Jongle Moi Catan. The other instruments on the track make reference to these... especially Polly Wolly Doodad.
The mouthbow and the whistling both make sounds the same way, by using the mouth as a resonating cavity, so they both play harmonics in the same range. I think this sound is awesome!