If you ever get stung by a tarantula hawk, Justin Schmidt has some advice: "Lie down and scream." The entomologist has endured the sting of that wasp, along with the stings of 82 other insects from around the world, as part of what FiveThirtyEight describes as an obsession with "codify[ing] the pain associated with various stinging insects." He's even come up with the Schmidt Sting Pain Index, which is included in his recently released book, The Sting of the Wild. The index runs from one to four; the aforementioned wasp's sting comes in at a four, and Schmidt likens it, per NPR, to this scenario: "A running hair dryer has just been dropped into your bubble bath." Compare that with the mud dauber wasp, whose sting is akin to “jalapeno cheese when you were expecting Havarti”; it registers as a one, to the common honeybee's two.
In addition to providing colorful, connoisseur-grade descriptions of the pain caused by stings, the Sting of the Wild provides all sorts of information about stinging insects. For instance, stingers evolved from the tubes through which eggs are laid, ovipositors, so only female insects can sting. Male insects fake it, Schmidt tells National Geographic, by “curling their abdomen around and jamming it into you,” in hopes you'll let them go. Butterflies, moths, and other insects that don't sting don't need to, another entomologist tells National Geographic. They lay their eggs on the surface of plants, in a process that doesn't require an ovipositor, hence, no stinger. When asked whether he wants to be stung, Schmidt tells NPR, "Want is kind of a dual word. I want the data, but I don't want the sting." (Another researcher has determined the most painful spot to get a bee sting.)