Microscopic swimmers with visual perception of group members form stable swarms

Birds, fish and bacteria often gather into groups or swarms. This so-called collective behaviour requires all group members to continuously and reciprocally adapt their movements. It can be a challenging task, however, for researchers to ascertain the specific environmental stimuli that individuals respond to within the context of their group; in addition to optical and acoustic information, flow resistances or chemical messengers can also play a role. By designing experiments with artificial mi...