Justin Schmidt does not have any tattoos or piercings. Not that he’s afraid of getting pricked. Or rather, stung. By bugs. Schmidt’s been stung by many, many, many bugs. Tiny, squishable things that leave temporary marks, but would probably have the most inked-up Hells Angel shaking in his chaps.
Because the pain of an insect sting is not normal. It’s like getting stabbed with a pencil point. Or like a single drop of hot oil. Hydrochloric acid on a paper cut. Walking on charcoal with a rusty nail in your heel. Hot oil spilling all over your hand. Schmidt is a connoisseur.
Years and years ago, the biologist became interested in how different stings from different insects made him feel different sensations. With a background in chemistry, he figured there must be something molecular at play, so he started keeping track. That led to the Schmidt Pain Scale, a way to compare different stings to one another, accompanied by delightfully excruciating prose. Now he’s written a book, The Sting of the Wild, to explain how stinging insects evolved (again and again), and why he finds them so beautiful.
The first thing Schmidt wants you to know is that pain is an illusion. “It is kind of this trickery that our body manufactures as a signal that damage is occurring,” says Schmidt. “It’s not truthful, it’s just saying nerves are stimulated. You have all these billions of endpoints throughout your body, and when you stimulate one of those it gets to the base of the brain and through some fancy dancy computer that our biology has engineered that says ‘Hey!!! Get that hand off the stove or away from that bug or whatever is causing the pain.'”
For insects, hijacking this pain response was an evolutionary coup d’etat. Think about it. You are a prehistoric beta-wasp, and some predator decides to snatch you up. You respond with your only possible defense: You can stab them with your ovopositor, the long, pointy organ you use to lay your eggs. You get the first strike, but the critter shrugs off your little poke. “Those with lesser or no sting were at the whim of whatever bird, lizard, or toad was out there and became the end of a genetic line,” says Schmidt.
But say you happened to have some little genetic mutation that causes your ovopositor to secrete certain molecules. When you stab your ovopositor into that hungry predator, the molecules bind to pain receptors on your attacker’s nerve cells. OUCH!
Pain is branding that predators tend to avoid. “Predators are smart, they learn,” says Schmidt. And stinging insects evolved coloration to advertise their sting further. Black and yellow, bright red, white and black: You know what to avoid.
But that isn’t all. Predators are smart. An insect sting might hurt, but if it does no damage, the pain doesn’t mean much. “That’s where the toxicity component comes in,” says Schmidt. Other molecules can mulch cellular machinery, causing organ failure and death. “This is the truth in the advertising.” Thus, venom has two basic properties: toxicity and pain. Scientifically, the former is easy to measure: Just observe the physiologic response provoked by the venom. Pain is more difficult, subjective. That’s where Schmidt came in.
An Education in Pain
The pain scale started in graduate school, when Schmidt and his wife Debbie were studying harvester ants at the University of Georgia. One day, out in the field, he got stung by one. He writes:
The pain, delayed at first, became piercing and excruciating. Then, it progressed into waves of deep, throbbing visceral pain, as Debbie, who also got stung in the operation, described as “deep ripping and tearing pain, as if someone were reaching below the skin and ripping muscles and tendons; except the ripping continued with each crescendo of pain.
Naturally, he wanted more. Wait, what? “I said wow, I’ve been stung by everything, and these were entirely different,” he says. Harvester ants had venom chemistry that was different from other stinging ants he had studied. So he and his wife embarked on a summer road trip, collecting different ant species across several states. “I was comparing the chemistry and toxicology, and while I was at it I was getting stung.”
So Schmidt started keeping notes. He devised a scale, one through four, to rate the pain associated with each sting. “I wanted a small scale, so you could clearly tell the difference between two numbers,” he says. In addition to the number, he would write a short description of the pain. Apis mellifera, the Western honey bee (“Burning, corrosive, but you can handle it. A flaming match head lands on your arm and is quenched first with lye and then sulfuric acid.”) became the anchor against which all other stings are measured, a solid two on the Schmidt scale. “Honey bees exist all over the world, and everyone has been stung by one,” he says. “Just compare this most recent sting to your memory of a honey bee and then figure out if you you had a choice, which would you rather get stung by?” If you prefer a honey bee, then the thing you got stung by is a one. If not, then it is a three or (god forbid) a four.
The complete Schmidt Pain Scale is printed for the first time in the back of his book. Alone, it is worth the price tag. But stick around for the rest of the book, which–amid countless stories of being stung–explains why all that pain is worthwhile. Because science.
The molecular differences behind those varied pain experiences show that different species of insects evolved venom independently, and many times over. “We know that the reason a honey bee sting feels like a cigarette ash is because it has a peptide called melittin that chews up your cell membranes where the venom is injected like a microblender,” he says. Wasp stings, on the other hand, burn deeply, acutely, partly because of mysterious peptides called kinins.
Schmidt says he is not looking for new stings. But then he tells certain stories. Like the time he saw a huge wasp called a cicada killer sitting on a flower on his way back to the lab. “In all the literature only one person ever got stung, and it was under the fingernail but he didn’t use any expletives,” he says. “People would ask if these things hurt, so I grabbed the thing and it stung me alright! I was predicting a one on the pain scale, like a sweat bee or a fire ant, but it surprised me. I called it a 1.5.”
And he admits, he has thought about getting tattooed. “I’d like to get a tattoo if I went to Borneo and was accepted into a headhunter community,” he says. “They cut you up on your back and mark your wounds with charcoal.” Yep, totally normal guy.