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Tamandua is a genus of arborial anteaters with two species, the southern tamandua (Tamandua tetradactyla) and the northern tamandua (Tamandua mexicana). Tamanduas have prehensile tails which help them grip the trees, bushes, and scrub where they hunt for ants, termites, and bees (which they vacuum up through a tubular mouth or capture with a 40 cm long sticky tongue). The two species inhabit a large swath of the Americas—the northern tamandua ranges from Mexico down through Central America and west of the Andes through coastal Venezuela, Columbia, and Peru. The southern tamandua inhabits the entire area surrounding the Amazon basin and ranges from Trinidad, through Venezuela, the entirety of Brazil, and into northern Argentina. Tamanduas weigh up to 7 kilograms (15 pounds) and grow to lengths of about a meter (3 feet).
Tamanduas have immensely powerful arms which they use for climbing and ripping apart ant and termite colonies. If threatened they hiss and release an unpleasant scent (they can also grapple by means of their formidable arms and huge claws). The creatures spend much of their time in trees and they nest in hollow trees or abandoned burrows of other animals. Tamanduas can live up to nine years. They are widespread but comparatively scarce.
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.
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.