There is a species of ants that could be considered one of the most grotesque because of the unusual choice of the “decor” of their home – the beheaded heads of their victims.
Scientific studies have consistently found that Formica archboldi ants tend to keep a lot of body parts of the victims around their homes. “A lot of ants are very clean, they will remove dead victims or food scraps,” said Adrian Smith, head of the Biological and Evolutionary Behavior Research Laboratory at the Museum of Natural Sciences in North Carolina.
Many ants take their waste out of the nest and put it in a pile, which also functions as a cemetery. The main idea to have a clean nest is to protect the queen from infections.
However, Formica ants “leave a lot of their garbage in the nest,” says Smith, who examined these insects for two years and conducted a study in 2019. “When you open their nests, you find a lot of body – probably because they did not throw their garbage ”.
Born in Florida, these ants that collect skulls, especially as trap-eating ants (Odontomachus brunneus) – are usually not an easy target.
Unlike other ants, Formica does not sting. Instead, they spray a dose of formic acid on their victims, which can completely incapacitate an ant trap. “A spray can remove a trap ant and a Formica ant could knock down a trap ant, a remarkable feat given that trap ants are usually known as ferocious predators,” says Smith.
Most of an Ant’s diet is trap ants. “We suspect he would kill two or three a day,” Smith said. And skulls are not easily digested or decomposed: “They are the hardest part of the exoskeleton, they are all hollowed out, all the muscle is gone, it’s just the heads or skulls,” he said. “They’re like thrown away chicken bones.”
Another theory is that Formica ants keep debris around to chemically mimic the trap ant they feed on. “When they touch each other with their antennae, they actually smell,” says Smith. “One way to buy the chemical, if not to make it yourself, is perhaps to keep the carcasses they acquire to maintain the smell of these ants.”
“There are rich details around us that we overlook or don’t pay attention to,” says Smith. “These types of ants have always been in Florida, I’ve known about these ants and their strange collections of body parts since the 1930s, but no one took the time to study them. These studies give us a reason to appreciate these things, to admire them and to protect them ”.