A remarkable strategy of deception and chemical warfare has been observed in parasitic ants: they infiltrate colonies of related species, trick workers into killing their own queen, and then usurp her position. This behavior, reminiscent of biological manipulation seen in horror fiction, highlights the brutal efficiency of some insect societies.
The Parasitic Takeover
Around 230 ant species are known parasites, exploiting the labor of others. Some species directly kill the host queen before laying their own eggs, while others, like Lasius orientalis, employ a more insidious method: manipulating the colony from within. Researchers led by Keizo Takasuka at Kyushu University in Fukuoka, Japan, documented how these parasitic queens trigger the violent overthrow of their host.
Chemical Warfare and Deception
The process begins with the parasitic queen evading the colony’s defenses, often by masking herself in the host colony’s scent. Once inside, she attacks the resident queen with a chemical spray – suspected to be formic acid – delivered from an abdominal orifice. This chemical acts as a signal, fooling the worker ants into perceiving their own queen as a threat.
The workers then attack and kill their mother queen, clearing the way for the parasite to lay her own eggs. This takeover is not instantaneous; it requires multiple chemical attacks and sustained aggression from the workers before the host queen is eliminated. Once the parasitic queen is in control, the workers tend to her offspring without discrimination.
Evolutionary Advantage
Takasuka suggests this strategy provides a significant evolutionary advantage. “If the parasitism succeeds, it allows the new queen to pass through the vulnerable founding phase far more safely than founding a colony alone.” The parasitic queen bypasses the risks of establishing a colony from scratch by hijacking an existing, functional society.
Broader Implications
Chris Reid at Macquarie University in Sydney, Australia, emphasizes the difficulty of studying such behaviors due to their occurrence within hidden underground nests. “This kind of natural history detective work is vital for improving our understanding of these super important insects.”
Further research could yield insights into controlling invasive ant species, which pose a major threat to ecosystems worldwide. By understanding the mechanisms behind this parasitic manipulation, scientists may develop targeted strategies to disrupt these destructive takeovers.
The parasitic ant’s brutal efficiency underscores the ruthless logic of natural selection, where survival often depends on deception, manipulation, and the willingness to exploit others
