Crowd Control

In John Boorman's under-rated sequel to The Exorcist, a possibly hallucinated scientist demonstrates the parable of a "good locust," whose influence on neighbouring insects can prevent harmless solitaries from gathering into voracious swarms. A more unsentimental view has been taken by contextually real scientists at the Max Planck Institute, who have discovered a pheromone which prevents locusts eating one another and are hoping to find ways of reducing its effectiveness. Locusts often use cannibalism as an incentive to community dynamism, but their swarming is a major nuisance to Homo sapiens ipsedixit, a species which long ago developed nobler reasons for slaughtering its own than mere brute survival.