We recently discovered that there are two different species of parasitic ants, Lasius orientalis And Lasius umbratuswho love work less than one would expect from animals who have become proverbial for this very reason.
In simpler words: they are lazy, and instead of building their nests they wait for two other species of the same genus to do so, Lasius flavus And Lasius japonicusand then usurp their queens and take their place.
But how do they do it? A new study published in Current Biology reveals their secret weapon: chemical warfare.
Duel. L. orientalis And umbratus they are not the only two species of ants that parasitize other people’s nests, although this usually happens within the same species, not between different species as in this case. Above all, when an ant wants to conquer another nest it very often uses a direct method: it challenges the queen in single combat and, if it defeats her, takes her place. These two species, however, use a more subtle strategy.
Fatal cocktail. There are small differences between the techniques used by the two species, but the general line is the same: the ants enter the nest they want to conquer and spray the queen with a cocktail of chemicals. When they reach a certain concentration, these substances trigger the reaction of the colony’s workers, who identify the queen as an enemy and dismember her within a few days. At that point, the parasitic ant can make its triumphant entry into society.
Spy undercover. You might wonder how these animals manage to gain access to the rival nest without problems. The answer seems to come straight out of a spy film: the ants intercept a worker while she is outside the nest and use her to “steal” her smell, so as not to be recognized as enemies by the colony. This way they have easier access to the room where the queen is.
The last question. One last question remains: why do the rebel workers not elect a new queen chosen from among the members of the colony, but on the contrary accept the intruder without problems, let her lay her eggs and also take care of her?
The answer is not yet clear, but studies on ants Lasius and their interactions will continue, and soon we will understand something more.
