French entomologist Jean-Henri Fabre (1823–1915) once performed extensive studies on processionary caterpillars. When traveling, these insects, with their protective stinging bristles, parade nose to tail, each following the other in a long train.
In one experiment, Fabre acquired a large flower pot, placed water and pine needles—the caterpillar’s favorite food—in the center of the pot, and then arranged the caterpillars one after the other on the rim of the pot. Around they went, around and around and around.
