Start playing the video above, and after you're suitably grossed out by the close-ups, skip to about 0:45. These are insects called hairy crazy ants — that is what they’re really called — and they are terrifying. How do they move that fast?

These guys are invading the American South. They are called hairy, because their bellies are hairy. They are called crazy, because they move crazy fast, and also they are crazy with nothing to lose. And they're hard to kill: if one dies, the others swarm the site to attack the danger. This one guy in Texas tried to test out a pesticide on a half-acre of land, and a month later he had "two inches of dead ants covering the entire half-acre … It looked like the top of the dead ants was just total movement from all of the live ants on top of the dead ants." Aaauuuuugh.

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