Argentine ant supercolonies locked in deadly territorial war

A massive and ongoing conflict between Argentine ant supercolonies in San Diego has claimed millions of lives in what scientists describe as an unusual display of insect warfare. The five rival colonies have established themselves as dominant forces in the region, each defending their territory with relentless aggression against neighbouring colonies.

Unlike most territorial animals, these Argentine ants have disregarded the 'dear enemy effect'—a biological phenomenon where animals recognise and show restraint towards familiar rivals. Instead, the supercolonies engage in continuous battles along their shared borders, resulting in devastating casualties that have reached approximately 15 million ants.

Research indicates that despite the ongoing violence and high death toll, the rival supercolonies have reached a state of military stalemate. Each colony maintains fixed territorial boundaries, with neither side able to significantly expand or overpower the others. This equilibrium suggests the conflict could persist indefinitely, creating a permanent state of war among the populations.

Scientists studying the phenomenon note that the scale and intensity of the Argentine ant conflicts represent a rare example of prolonged territorial warfare among insects. The supercolonies, which consist of thousands of individual nests linked by a chemical communication system, operate as unified military forces, demonstrating sophisticated coordination in their ongoing territorial disputes.