Movie S1.

Defecation of fluorescently (GFP) labeled colloidal particles (1 μm in diameter) by an N2 C. elegans worm. The worm was transferred onto a lawn of nonfluorescent bacteria (E. coli, OP50) after feeding on bacteria seeded with fluorescent beads. The movie was captured at 10 frames per second (fps) and played back in real time. The length of the worm is about 1 mm.