Did you know that before they swarm, and ravenously destroy crops, locusts are grasshoppers? It is true. Before taking flight en masse to travel to, descend on, and mercilessly consume fields, they are harmless, lonesome grasshoppers munching on tiny and unnoticed bits of vegetation. But as those docile grasshoppers multiply, their density increases. When it gets high enough their personal space overlaps and they occasionally bump into each other.
Well scientists have now shown that it is exactly that contact–jostling in confined areas and bumping into others–that turns a pleasant, calm grasshopper into an asshole of biblical proportions. In this way I think humans and locusts are much alike.