The Wasp That Delivers 'Instantaneous, Debilitating Pain'
"Ouch!" has never sounded so authoritative. Out of the mouth of Justin Schmidt, UA entomologist and author of the only scientific rating system of insect stings, it takes on a whole new meaning. In this excerpt from his recent book, "The Sting of the Wild," Schmidt tells us about the fascinating life of the tarantula wasp.
By Justin Schmidt
Stung by a tarantula hawk? The advice I give in speaking engagements is to lie down and scream. The pain is so debilitating and excruciating that the victim is at risk of further injury by tripping in a hole or over an object in the path and then falling onto a cactus or into a barbed-wire fence.
Such is the sting pain that almost nobody can maintain normal coordination or cognitive control to prevent accidental injury. Screaming is satisfying and helps reduce attention to the pain of the sting. Few, if any, people would be stung willingly by a tarantula hawk. I know of no examples of such bravery in the name of knowledge, for the reputation of spider wasps — specifically tarantula hawks — is well known within the biological community. All stings experienced occurred during a collector’s enthusiasm in obtaining specimens and typically resulted in the stung person uttering an expletive, tossing the insect net into the air and screaming. The pain is instantaneous, electrifying, excruciating and totally debilitating.
Howard Evans, the great naturalist and author of the eminently enjoyable books "Life on a Little Known Planet," "Wasp Farm" and "The Pleasures of Entomology," was an expert on solitary wasps. Howard, a slight, reserved man with a shock of white hair and a sparkle in his eyes, was especially fond of tarantula hawks. Once, in his dedication to the investigation of these wasps, Howard netted perhaps 10 female tarantula hawks from a flower. He enthusiastically reached into the insect net to retrieve them and, undeterred after the first sting, continued, receiving several more stings, until the pain was so great that he lost all of them and crawled into a ditch and just sobbed. Later, he remarked that he was too greedy.
I know of only two people who were "voluntarily" stung by tarantula hawks. I say "voluntarily," as both were film actors performing their duties, which, among other things, "encouraged" being stung. One was a young, handsome, athletic entomologist who knew of the wasps. He deftly reached into the large cylindrical battery jar and grabbed a wasp by the wings. He had her in such a position that her sting harmlessly slid off his thumbnail. We prattled for a minute or so about tarantula hawks while the camera scanned close up to the long sting as it slid harmlessly, missing its mark. Then, with a great heave, the wasp pulled its abdomen back and thrust the sting under the nail. Yeee...ow (we can’t recall if any expressions unsuitable for general audiences were uttered), the wasp was hurled into the air and flew off unharmed. One point for wasp, zero for human.
The other actor was a solidly built fellow who could easily have been a football linebacker, and who was a master of performing pain-defying acts of bravery. I, however, was charged with catching the wasp and delivering it to the scene. Five or six tarantula hawks were easily netted from flowers of an acacia tree; unfortunately, the net snagged on some thorns, and all but one wasp escaped. The remaining wasp was a male, so I summoned the cameraman to demonstrate how males cannot sting and are harmless. I reached in and casually grabbed "him." The him was a her. Yeee...ow, except this time it was me. I managed to toss her back in the net, while attempting to explain my blunder and pain on camera. Unfortunately, I was not the actor, so the footage was relegated to some obscure studio archive, perhaps someday to be resurrected on YouTube. That episode over, the tarantula hawk was delivered to the rightful actor. He grabbed her, was stung, and showed no reaction beyond a begrudging "ouch, that did hurt a bit." I figured the guy had no nerves. But his director handed him a habanero pepper, the tarantula hawk of chili peppers, which he enthusiastically bit into. He became instantly speechless, convinced fire was blasting from his mouth, nose and ears. Apparently, he did have some nerves — sensitive at least to chili peppers.
Tarantula hawks have never been recorded as a part of human warfare, but they might be candidates in some future altercations, and surely they come a close second in personal battles. Howard Evans, in a moment of exasperation, wrote of an experience in Mexico: "(Tarantula hawks) are spectacular creatures, on a number of occasions I collected these wasps in the Southwest and in Mexico, followed by a group of urchins who asked questions and tried to help. My trick to be rid of them was to pick a tarantula hawk off the flowers with my fingers and show it to them. Of course I always picked up a male, which cannot sting. But my curious followers would pick up a big one, usually female, and quickly decided they wanted no more of that."
How could such a small animal as a tarantula hawk embed itself so strongly in the human psyche and win? Several years ago I attempted to address this question in a paper titled "Venom and the Good Life in Tarantula Hawks: How to Eat, Not Be Eaten and Live Long." The natural history of tarantula hawks provides some insights. Tarantula hawks are the largest members of the spider wasp family Pompilidae, a family of some 5,000 species strong that prey solely on spiders. The feature of tarantula hawks that makes them so special is their choice of the largest of all spiders, the fierce and intimidating tarantulas, as their target prey. The old saying "you are what you eat" rings true for tarantula hawks: If you eat the largest spiders, you become the largest spider wasps. As with other spider wasps, the female wasp provides each young with only one spider that serves as breakfast, lunch and dinner for its entire growing life. The law of supply and demand applies: Large spiders produce large wasps; small spiders produce small wasps.
The story doesn’t end here. Momma wasp is not entirely at the whim of fate and fortune in the size of spiders she encounters, with her young randomly enduring the consequences. She has the special ability to choose the sex of her babies. Hymenoptera are oddballs in the genetic world. Females are produced from fertilized eggs, and males are produced from unfertilized eggs. This not only means males have half the genetic information of females (but that does not translate into males being half as intelligent as females, a thought that might enter the human female mind). It also means Mom can choose to produce a son or a daughter by selectively allowing stored sperm to fertilize the egg. In the tarantula hawk world, females are valuable. They do all the work, take all the risks of capturing the spiders and have to drag a spider sometimes eight times their weight to their burrow. Thus, females need to be big and strong to do the job efficiently and to produce the most young. Males, however, mainly sip nectar from flowers, chase other males and mate with females. A small male can mate with a female, so size is not so crucial, though a bigger male is usually more successful in winning more females. Mother tarantula hawks choose to give the valuable resources of large tarantulas to female young and small tarantulas to male young.
Excerpted from "The Sting of the Wild" by Justin O. Schmidt. Published by Johns Hopkins University Press © 2016. Reprinted by permission of the publisher.
The UA's Justin Schmidt was a guest on NPR's "Science Friday" last week, explaining why categorizing bee, ant and wasp stings, on his scale of 1 to 4, offers important data to our understanding of those insects. Click here for more.
Check out the world's most — and least — painful stinging insects in one handy chart.
Learn more about Schmidt's book, "The Sting of the Wild," at the publisher's website.
TopicsScience and Technology
University of Arizona in the News