Inspired by the collective dynamics of bacteria like E. coli and Bacillus subtilis, researchers at the University of Twente asked a simple but fundamental question: what happens when artificial swimmers are made rod-shaped rather than spherical, and how does shape control how they move as a group? "These dumb yet active rods follow only the laws of physics, which help to uncover the mechanics of collective bacterial behavior," says Hanumantha Rao Vutukuri. Their findings appear in Science.