To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video Movie 1 Response to sound in a monarch caterpillar. Monarch butterfly caterpillar on a milkweed leaf responds to one second long, 300 Hz tones by flicking. Hearing in caterpillars of the monarch butterfly (Danaus plexippus) Chantel J. Taylor, and Jayne E. Yack Journal of Experimental Biology 2019. 222:None-None; doi: 10.1242/jeb.211862 Download Original Video