The latest internet Meme is the Harlem Shake, and I think this is one of the best versions. A little background:
“Harlem Shake” (not the hip hop dance style) is the title of a 2012 heavy bass instrumental track produced by Baauer. In February 2013, the song spawned a series of dance videos that begin with a masked individual dancing alone in a group before suddenly cutting to a wild dance party featuring the entire group.
And here you go: Harlem shake of the butterflies.
What you are looking at is a bunch of chrysalids, or the pupal stage of a butterfly where it transitions from a caterpillar into an winged adult. They are still able to move and respond to stimuli in this stage, even though they lack functional legs. They are commonly reared like this in butterfly houses.