The annals of psychology are littered with the unreplicated remains of behavioral hypotheses and quirky effects, and if no other studies had been performed in the wake of this brief experiment, the “watching eyes effect” probably never would have garnered attention. But four years later, Bateson and Nettle rekindled their initial workplace study in a new arena. They hung up two different sorts of posters at a local restaurant, one with pictures of eyes, and the other with flowers. Both types of posters featured text asking patrons to clean up after themselves. As it turned out, the diners who ate in the presence of the eye posters were twice as likely to follow the signs’ directions and throw away their leftover food and trash. What’s more, when the duo repeated the experiment with posters of eyes and flowers containing messages unrelated to littering, the effect persisted.

Images of eyes have also been shown to alter behavior for the better in other contexts. In an eleven-week field experiment conducted in a supermarket, donations to charity collection buckets rose 48 percent when eyes were displayed nearby. Other studies have shown that images of eyes placed on a college campus or in the vicinity of bus stops leads to a reduction in litter, either because people are less likely to litter in the first place, are more likely to pick up others’ trash, or spend more time picking up others’ trash.