In this short video, from the 2009 World Science Festival, Bobby McFerrin demonstrates the power and universality of the pentatonic scale. Using his audience as an "instrument", McFerrin dances across a giant, imaginary keyboard - think Tom Hanks in the movie, Big - to create a visual metaphor for the pentatonic scale. As the performance progresses,, the audience sings a simple pentatonic melody, (in tune, no less!) while McFerrin, still dancing, sings a duet with his impromptu chorus. By the end, the audience, with no prompting other than McFerrin's " dance steps, sings a complete, two-octave, pentatonic scale!