Ants are paramedics on the battlefield

Ants tend intensively to the wounds their fellow colony members sustain in battle. This behaviour is likely unique in the animal kingdom.

African Matabele ants (Megaponera analis) treat the open wounds of their injured companions – and do so with remarkable success. Without treatment, 80 percent of the injured die; after «medical» care, the mortality rate drops to just ten percent. This is the conclusion reached by researchers at the University of Würzburg in their latest study.

High risk of injury

The Würzburg biologists believe that this behaviour has not previously been observed anywhere else in the animal kingdom. In the daily life of Matabele ants, the risk of injury is very high: these insects, which are widespread south of the Sahara, go on raiding parties two to four times a day. In columns of 200 to 600 individuals, they set out to attack termites at their feeding sites, killing many workers and dragging them back to the nest, where they ultimately consume their prey.

However, termite soldiers – with their well-armoured heads and powerful mandibles – do not submit to these raids without a fight. When battle commences, the ants suffer both fatalities and injuries – their legs, for example, are often partially bitten off. When ants are wounded in this way, they release a chemical signal that prompts their fellow colony members to carry them back to the nest.

The weakest reject help

Once back at the nest, the ants intensively “lock” the open wounds of their fellow fighters, often for minutes at a time. “We suspect that in doing so they clean the wound and may even apply antimicrobial substances through their saliva to reduce the risk of infection by fungi or bacteria,” says Würzburg researcher Erik T. Frank.

Another detail points toward optimal use of resources: severely injured ants — for example, those that have had five of their six legs bitten off — are not helped on the battlefield. The decision about who is rescued and who is not, however, is made not by the helpers but by the injured themselves. “They simply do not cooperate with the helpers and are then left behind,” says Frank. This ensures that energy is not wasted. More on fascinating wildlife and Education.