Early American colonists mistook cicadas, compact insects with dark exoskeletons, glistening red eyes, and big wings, for locusts—and in light of recent events, we understandably might do the same. Billions of them, from the ominously named Brood X group of periodical cicadas, will emerge from the earth in the coming weeks, with epicenters in Washington, D.C., Indiana, and Tennessee. They’ve been living underground for 17 years, feeding on tree and plant sap and, once the soil warms up, will claw their way toward the surface to breed. You’ll know when they arrive: male cicadas rapidly vibrate a pair of ribbed membranes called “tymbals,” which sit on either side of their abdomens, to create a shrill, cacophonous mating call that varies from a genial whistle to a raspy din.