I was reading on Cracked.com about the tarantula hawk, a giant wasp that hunts tarantulas and has one of the most painful stings on earth. We know this because the tarantula hawk ranks at number two on the Schmidt Pain Index, just behind the bullet ant. Who is Schmidt, you ask? Cracked says he "volunteered to be stung by every goddamn awful thing in existence despite nobody ever asking anybody to ever do that." Schmidt supposedly has described the sting of the tarantula hawk as "blinding, fierce and shockingly electric." Can the Straight Dope science department confirm this nonsense? If it is true, why did this guy Schmidt do it?
Illustration by Slug Signorino
This story has been shamelessly exaggerated. Having spent half an hour on the phone with entomologist Justin O. Schmidt of the Southwestern Biological Institute in Tucson, Arizona, I can confidently report he didn’t volunteer to be stung by every goddamn awful thing in existence. It just sorta happened.
As a leading expert on stinging insects, Schmidt spends a lot of time capturing bugs for his research, going after some of the most toxic, aggressive, and algogenic (i.e., pain-inducing) species on earth. Inevitably accidents occur.
For example, one time Schmidt found himself clinging to a tree suspended over a Costa Rican gorge Indiana Jones-style while enraged wasps squirted venom in his eyes. You or I in this situation would say … well, actually we wouldn’t say anything. We’d just shriek like frightened babies. Schmidt for his part admits it wasn’t one of his better days but as a scientist wasn’t about to let useful data go to waste. After the agony receded sufficiently he jotted down a few notes for the pain index.
Schmidt first used his index in a 1984 study investigating whether a certain physiological sting reaction was correlated with pain. It wasn’t, but Schmidt realized quantifying pain had its uses and elaborated on the index in a 1988 paper and again in 1990, providing ratings for 78 species and 41 genera. All were based on stings he or associates had experienced personally.
The Schmidt Sting Pain Index is a five-point scale, as follows:
- Sting level 0 is virtually imperceptible — the stinger doesn’t penetrate the skin.
- A level 1 sting is the sharp prick you get from a sweat bee or a fire ant, a rating that seems surprisingly low until you realize hardly anybody gets stung by just one fire ant.
- A typical level 2 sting is produced by the honeybee, the benchmark of sting pain.
- But things can get much worse. For the archetypal level 3 sting you want a harvester ant (genus Pogonomyrmex), whose sting combines intensity with duration — the pain can last four to eight hours.
- Finally, there’s a level 4 sting, which is as bad as it can get. Schmidt knows of only three critters capable of inflicting level-4 suffering: the warrior wasp (Synoeca septentrionalis), a two-and-a-half-inch-long black bug found in the tropics; the bullet ant (Paraponera clavata), also tropical; and the tarantula hawk (genus Pepsis), two inches long, which Schmidt can find in his yard in Tucson.
The tarantula hawk’s sting, Schmidt has been quoted as saying, feels like “a running hair dryer has just been dropped into your bubble bath.” However, for sheer aggregation of misery he rates the sting of the bullet ant slightly higher. Whereas the sting of the tarantula hawk fades after two to five minutes, the “pure, intense, brilliant pain” of the bullet ant remains at full strength for one to four hours and can linger for 12 hours.
As one might surmise given the nature of the research, the Schmidt index is subjective and based on limited data points. Schmidt says he’s been stung six to eight times by tarantula hawks and just once, in the forehead, by a warrior wasp. He acknowledges the pain can vary depending on where you get stung and how much venom was injected. For that reason he hedges his ratings, with bee stings ranging from 0 to 2.
This may surprise those relying for their scientific information on Wikipedia, which provides a chart of the Schmidt index listing precise decimal gradations for sting severity, with the fire ant rated at 1.2 and the bullhorn acacia ant at 1.8. These implausibly exact numbers don’t appear in any of Schmidt’s scientific papers, but rather were wheedled out of him by an editor at Outside magazine, who was trying to goose up a story for that publication in 1996.
One also mustn’t take seriously the wine-review-style descriptions accompanying the sting ratings. For example, the sting of a southern paper wasp is said to be “caustic and burning, with a distinctly bitter aftertaste. Like spilling a beaker of hydrochloric acid on a paper cut.” Such remarks lack empirical basis, Schmidt cheerfully concedes, although if there’s anyone equipped to expound on the fine points of pain, a guy who’s been stung by 150 different species in his lifetime is probably it.
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