Matabele Ants Give Life-Saving Treatment to Injured Companions, Treat Infected Wounds With Self-Produced Antibiotics

It has been known that certain ants have antibiotic properties. For the first time, one ant species has been observed using those chemicals to treat infected wounds of their companions.

Hostile Ant Species

Matabele ants (Megaponera analis) are considered one of the world's biggest and most violent ant species. They are named after the Matabele tribe, fierce warriors from southwestern Zimbabwe who overwhelmed other tribes in South Africa during the 1800s. These highly specialized predators are widespread south of the Sahara. As the most warlike of all ant species, they rarely lose the battles they wage on their enemies.

This group-raiding ponerine species has a narrow diet because they only eat termites. They raid termites two to four times a day, killing the workers and bringing them back to their nest, where the rest of the colony will eat them. Every time they raid, 200-600 ants march out, preying on termites.

However, the termites are not defenseless. These hunting expeditions are dangerous since the well-armored termite soldiers defend their colony using their powerful mandibles. While the termites are often overrun by their predators, they can still give powerful blows, heavily injuring or even killing the ants. Because of this, it is common for Matabele ants to become injured while hunting for food. Some of them even lose one or several limbs.

Targeted Wound Treatment

For decades, it has been known that Matabele ants are superior fighters, yet it remains a mystery where they get their edge on the battlefield. In a recent study, a team of researchers led by Professor Laurent Keller from the University of Lausanne and Dr. Erik Frank from Julius-Maximilians-Universität (JMU) Würzburg has discovered a sophisticated healthcare system displayed by Matabele ants. The findings are reported in the paper "Targeted treatment of injured nestmates with antimicrobial compounds in an ant society."

While observing ants in Comoe National Park on Ivory Coast, experts noticed that they carry out a kind of "triaging" where they decide who to help and who to leave behind. Matabele Ants, slightly injured and losing one limb, called for help by releasing pheromone. Meanwhile, the badly injured members that miss five legs resist help by flailing wildly if someone attempts to rescue them.

It is also interesting how the "medic ant" addresses the wound. Chemical analyses showed that the hydrocarbon profile of their cuticle changes due to wound infection. These changes allow the insects to distinguish between non-infected and infected wounds. After successfully recognizing the wounds, the ants diagnose the infection status of their injured comrades.

It was also previously found that injured Matabele ants recover 99% of the time, but only if other ants lick their infected wounds. Meanwhile, those not treated with their comrade's saliva only recover one out of five times. Scientists are mystified as to why this licking process heals wounds, but they theorized that ant saliva contains antimicrobial properties.

The study revealed that the saliva applied to the infected wounds contains proteins and antibiotics from the metapleural gland located on the side of the thorax. The secretion contains 112 components, half of which have wound-healing effects.