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Justin Orvel Schmidt (pictured above) is an entomologist who specializes in insect defenses. His greatest expertise is in the stings of hymenopterans—the bees, wasps, sawflies, hornets, and ants (although he also researches the toxic/chemical defences of other arthropods). In the early 1980’s Schmidt attempted to systematize the different medical and physiological effects of insect stings. This work led him to coauthor one of the comprehensive tomes on the subject of insect venom Insect Defenses: Adaptive Mechanisms and Strategies of Prey and Predators. Unfortunately for Schmidt, in the course of his researches, he has been stung/bitten innumerable times by various aggressive and toxic insects (and other creepy crawlies) from around the world.
Based on these experiences, Schmidt attempted to categorize the algogenic (i.e. pain-inducing) effects of hymenopteran stings in the now world-famous Schmidt sting pain index. This index is a captivating blend of subjective pain analysis, horrifying real world experience, and inventive poetry. The lowest sting on the Schmidt index is a 0—betokening a sting which has no effect on humans. The highest rating is a 4 which describes an experience of maddening absolute agony. The index became famous because of an interview with Outdoor magazine. Schmidt has since conceded that his descriptive efforts lack an empirical basis and that stings vary depending on body location and the amount of venom injected. Because of such admissions, Wikipedia took down its remarkable table of stings–which is a shame because the subjective descriptions gave the index its visceral power. Here is a sampling copied verbatim from “Retrospectacle: A Neuroscience Blog”:
1.0 Sweat bee: Light, ephemeral, almost fruity. A tiny spark has singed a single hair on your arm.
1.2 Fire ant: Sharp, sudden, mildly alarming. Like walking across a shag carpet & reaching for the light switch.
1.8 Bullhorn acacia ant: A rare, piercing, elevated sort of pain. Someone has fired a staple into your cheek.
2.0 Bald-faced hornet: Rich, hearty, slightly crunchy. Similar to getting your hand mashed in a revolving door.
2.0 Yellowjacket: Hot and smoky, almost irreverent. Imagine W. C. Fields extinguishing a cigar on your tongue.
2.x Honey bee and European hornet: Like a matchhead that flips off and burns on your skin.
3.0 Red harvester ant: Bold and unrelenting. Somebody is using a drill to excavate your ingrown toenail.
3.0 Paper wasp: Caustic & burning. Distinctly bitter aftertaste. Like spilling a beaker of hydrochloric acid on a paper cut.
4.0 Pepsis wasp: Blinding, fierce, shockingly electric. A running hair drier has been dropped into your bubble bath.
4.0+ Bullet ant: Pure, intense, brilliant pain. Like fire-walking over flaming charcoal with a 3-inch rusty nail in your heel.
While the work lacks rigorous empirical criteria, even the most relentlessly analytical critics seem to aver that being stung by over 150 different species of arthtopods gives Schmidt a certain robust validity. The literary merit of the metaphors is certainly genuine (although one hopes that the good Doctor Schmidt never actually dropped a hair dryer into his bubble bath or let misanthropic vaudevillians torture him with fire). Personally I have only been stung by sweat bees, honey bees, and yellow jackets, so I cannot testify to the more esoteric sting ratings (thankfully–since yellowjacket stings nearly did me in), however something sounds completely right about the yellowjacket sting description. I recall a moment of warmth which metastasized almost immediately into a sour panic-inducing pain which spread through my arm and then my body.
In conclusion, I salute Justin Orvel Schmidt as a man of science and a masochistic poet/performance artist. If he claims that a bullet ant sting is the worst hymenopteran sting, I see no cause to contradict him and I never want to think about it again.
Hey, look at that! It’s a delicate pale blue butterfly (Maculinea arion) from Europe and northern Asia. What could this ethereal creature have to do with the horror theme which this blog has been following as a lead-up to Halloween? In fact, what does the butterfly have to do with any of Ferrebeekeeper’s regular themes? Butterflies are lepidopterans rather than the hymenoptera we favor here.
As it turns out—the butterfly has a lot to do with hymenopterans. Maculinea arion, or “the large blue butterfly ” to use its not-very-creative English name, may look innocent as a butterfly, but in its larval stage the creature is both appalling and remarkable. Alcon caterpillars are myrmecophiles—which means the caterpillars live in association with ants. Despite the Greek meaning of ”myrmecophile” (to love ants) the relationship is anything but loving on the part of the Alcon caterpillar–unless love is meant in the same way as “to love ham”.
M. arion caterpillars are relentless predators of ant larvae. The way they obtain this fragile foodstuff is remarkable for sophistication and ruthless guile. When a caterpillar hatches, it lives for a few days on wild thyme or marjoram plants. The caterpillar then secretes a sweet substance which attracts red ants which carry the larva back to their tunnels.
Inside the ant hive, the caterpillar produces pheromones and chemical scents which mimic those of the ant queen. It also scrapes a small ridge on its first segment to produce the same noise as the ant queen. The ants are deceived by the caterpillar’s mimicry and they take it to the chamber where they rear their own larvae. The ants wait on the caterpillar as though it were the hive monarch and they even feed it ant larvae—their own undeveloped siblings. Once it pupates, the butterfly scrapes the inside of its chrysalis to continue the deception. When the butterfly emerges from its cocoon the hapless ants carry it outside and guard it as its wings harden—whereupon the butterfly departs to mate and lay eggs on wild thyme or marjoram plants.
The Maculinea Arion is not the only caterpillar to make use of this strategy. The Phengaris alcon butterfly acts in almost exactly the same way. Here is where the story becomes impressively crazy. A parasitoid wasp, Ichneumon eumerus, feeds on the alcon caterpillar inside the ant hive. The wasp infiltrates the hive by spraying a pheromone which causes the ants to attack each other. While they are busy fighting, the wasp lays its eggs inside the caterpillar. The wasp larvae hatch into the body of the caterpillar (which the ants think of as a queen) and they eat the caterpillar host safe in the cloak of this deception.
If an ant hive becomes too saturated with caterpillars it will die and all three species inside the hive will likewise perish). The red ants in this scenario are constantly evolving new pheromone signals to outcompete the caterpillars and wasps—which in turn coevolve with the ants. It’s strange to imagine the troubling world of deception, chemical warfare, and carnage just beneath the ground.
If you are wondering through the great untouched rainforests of the Amazon basin, you will sometimes come across a clearing devoid of all vegetation save for a few trees. These bare patches are known as devil’s gardens and are said to be the haunt of the fearsome Chuyachaqui (or Chullachaqui), a shape shifting demon which delights in causing misfortune to travelers. Although the Chuyachaqui’s default form is that of a small misshapen man with one hoof and one human foot, the demon can change shape into a person known to the traveler in order to mislead the latter to doom.
Scientists were curious about these small bare patches of forest. After carefully studying the ecosystem, they discovered that a force nearly as diabolical as the Chuyachaqui is responsible. The lemon ant, Myrmelachista schumanni, produces formic acid, a natural herbicide which it methodically injects into the plants in a “devil’s clearing”. The only plants which the ants leaves alone are Duroia hirsuta, “lemon ant trees” which have evolved a mutualistic relationship with the ants. The lemon ants keep the forest free of competing trees and plants, while the lemon ant tree is hollow inside—a perfect natural ant hive and its leaves provide a source of nutrition for the lemon ants (which are a sort of leaf-cutter).
Large colonies of lemon ant trees have been found which are believed to be more than 800 years old—far older than the life of any ant colony or individual tree. It is remarkable to think these ant/tree settlements have been part of the rainforest since before the Mongol conquests.
Velvet ants (Mutillidae) are not actually ants at all—the insects are classified as wasps even though female velvet ants do not have wings and appear to be tiny furry colorful ants. The Mutillidae family of wasps—which is made up of more than 3000 species– illustrates how closely wasps, bees, and ants are actually related. Male velvet ants look nothing like the females but are much larger winged creatures resembling other wasps. So great is the sexual dimorphism between the genders that it took entomologists a tremendously long time to pair the females with the males, and in many species the connection has still not been made by science. The genders do however both share a ridged structure called a stridulitrum, which can be rubbed or struck to produce chirps and squeaks for communication.
Female velvet ants are notable not just for their colorful fur but for their tremendously powerful sting which is so painful that they are nicknamed “cow killers.” Male velvet ants look like wasps but do not sting. The exoskeletons of velvet ants are tremendously hard to such an extent that some entomologists have reportedly found it difficult to drive pins through specimens. The dense hard coating helps the females invade the underground burrows of larger bees and wasps which the velvet ants sting and lay eggs on. When the velvet ant larvae hatch they feed on the paralyzed victims before metamorphosing into adult form and venturing into the world.
Velvet ants are found in warmer parts of the world particularly deserts. The majority of species are red and black but a variety of other colors are known including blue, gold, orange, and white. Unlike the social ants and termites, velvet ants are generally solitary, coming together only to reproduce with their strangely alien mates.
The smallest known snake in the world is the Barbados Threadsnake (Leptotyphlops carlae), a species of blind threadsnake so small they were only discovered in 2008 (despite living on a heavily populated, highly studied island). The adult snakes measure only 10 cm, (4 inches) long. Herpetologists believe these tiny snakes are at threshold of viable size for snakes: if they were any smaller they would not be able to hunt or reproduce.
Female Barbados threadsnakes lay a single egg which is huge relative to the size of the mother. The newly hatched snakes are already half as large as adults. Like caecilians or other blind snakes, Barbados threadsnakes are fossorial–they live and hunt underground (which is one of the reasons it took so long to find them). The little threadsnakes live on the larvae of ants and termites.
Not only are Barbados threadsnakes miniscule. Their remaining forest territory is tiny. Barbados is heavily developed and no original old growth forests exist. The threadsnakes live in secondary forests which regrew from the vestiges of long-vanished woods. Their entire habitat is thought to be no more than a square kilometer or two.
One of the strangest and most alarming creatures on the planet is the driver ant. Driver ants belong to the genus Dorylus which is comprised of about 60 species. In the larger Dorylus species, each worker ant is only half a centimeter long. The soldier ants which guard the hive are a mere 1.5 centimeters. Males, which can fly, are 3 centimeters long and the queen, the largest of the ants, is from 5 to 8 centimeters long. These are not the sort of sizes that allow one to play professional football, so what makes Dorsylus ants so fearsome? Well, there are lots of them. Driver ants form the largest colonies of all the social insects. They live in hives numbering more than 20 million individuals, all born by one single queen.
When marching or foraging, these hives can overrun and overpower much larger animals and generally everything that can do so gets out of their way (including mighty elephants).
Driver ants are usually found in the tropical forests of West Africa (although some species range into tropical Asia). Although capable of stinging, the ants rarely do so. They prefer to use their powerful sharpened mandibles to shear apart prey. Not only are these mandibles powerful the pliers-like pincers lock into a death grip if the ant itself is killed (or even beheaded).
Male driver ants fly away from the colony very soon after birth. If a colony of foraging driver ants comes across a male ant they rip off his wings and take him to mate with a virgin queen (after which he dies). The queen ant then lays 1 to 2 million eggs per month for the remainder of her life.
All driver ants are blind, but they have an acute sense of touch and smell. Larger columns follow scent trails laid down by scouts. The ants eat any animal life they can get their mandibles on (although the staple of their diet is apparently worms).
When driver ants have stripped the animal life from a particular section of the forest they nomadically pull up stakes and move on en masse. Developing larvae are carried in temporary nests made up of the living bodies of worker ants. Foraging columns or hives on the move are dangerous. While healthy animals can escape, injured or trapped animals can be killed by the ants which enter the mouths and nostrils of victims. One shudders to think of the bad ends which have befallen people who were wounded, bound, or seriously drunk when driver ants were passing through. Farmers however have a different relationship with the ants which can clear entire fields of all agricultural pests in an afternoon.