Imagine a species that is only one millimetre long and has only a limited swimming ability. Yet, its mobility is sufficient for moving, feeding and reproducing in freshwater and seawater. That’s exactly what a type of zooplankton of the crustaceans family — namely the calanoid copepods — does. In a study, physicists shed new light on how these zooplankton steer large-scale collective motion under strong turbulence.