No eyes, cannibalistic habits and the primacy of “faster bite” in the animal kingdom: the ant Mystrium camillae it is certainly one of the most bizarre products of biological evolution. This rare species of subterranean ant belongs to the subfamily Amblyoponinae, commonly calledDracula ants” or vampire ants for the tendency to feed on vital juices of their larvaebut without killing them. Their mandibleswell adapted to snap shut, lock in 23 microseconds reaching a speed of 90 meters per second, the equivalent of 324 kilometers per hour. This is the fastest individual movement in the animal kingdom.
The mandibles of Dracula ants
Almost all species of Amblyoponinae have long and strong mandibles used in hunting and defense, but in a particular species, the Mystrium camillaethis specialization reaches record numbers. The mandibular structure of the Mystrium genus is different from other ants: the three parts that usually make up the mechanism are fused together. The shape is also different, with two long curved arms which join at the end, leaving ample space between them. Rather than snapping shut on prey from the open position, Mystrium passes its prey through the space between its jaws and then applies tremendous pressure to both arms until one slides over the other, closing. The operation resembles it in its mechanics snap of two fingers.
The record-breaking bite of the vampire ant
Although the speed of bite closure of vampire ants was already known, it was in a 2018 article published in Royal Society Open Science that US researchers were able to measure it precisely for the first time with the help of high-speed cameras. By filming the ants at 1000 frames per second, the researchers observed that the duration of total closure can occur in less than a milliseconda thousand times faster than a human snap of the fingers and five thousand times faster than the blink of an eye. The observed velocity reached i 90 meters per second or 324 kilometers per hour, with an estimated acceleration greater than 106 x g. This would be the fastest movement produced by a biological organism.
Characteristics and nutrition of vampire ants
The “Dracula Ants” are a cosmopolitan subfamily of very specialized ants with an exclusive life in an underground environmentwhere food resources are scarce and lighting is absent. Dracula ant workers are indeed completely blind: the eyes are very small or even absent in many species. They live in small colonies and feed mainly on other subterranean arthropods, particularly centipedes, but they have also developed a bizarre feeding adaptation responsible for their nickname. Adult vampire ants do in fact practice non-lethal infantile cannibalism: they bite the cuticle of the larvae, enough to pierce it but without killingand suck theirs hemolymphthe equivalent of blood in invertebrate organisms.
This behavior, although unusual, helps the colony to survive because it makes up for the vampire ants’ inability to exchange food with each other. Most social animals such as ants, acting as a “single organism” for the survival of the colony, engage in some type of food sharing, called trofallassi: members of the same colony pass food to each other via their mandibles. Vampire ants are unable to do this, and therefore to balance the overall nutritional supply in the colony and survive periods of famine, the queen and the hungriest workers occasionally feed on a few drops extracted from the larvae, which they survive without too much damage to the operation.
