No, it isn't the start of a joke (though that would be a good opening). Previously I wrote about percussionists that influence the perception of duration through physical gestures. Another study shows how vocalists use head movement and facial gestures to influence the perception of melodic intervals. Listeners were asked to rate the size of ascending intervals that three performers sang. Three physical movements of the singers were measured: head displacement, eyebrow displacement, and lip displacement. All three movements correlated with the size of the intervals, so the singers moved their heads, eyebrows, and lips more with bigger intervals. These movements also influenced the listeners' ratings of interval size, so a bigger physical movement made the listener rate the interval as larger.
William Forde Thompson and Frank A. Russo, "Facing the Music," Psychological Science Vol. 18 no. 9(Sept. 2007), 756-757.