A unique species of soldier ant braves the battlefield to rescue stricken comrades, scientists have found.
Erik T. Frank, who led the research on African Matabele ants, believes it's the first time any insect species has been found to dress the wounds of other individuals.
Dr Frank said: 'We suppose that they do this to clean the wounds and maybe even apply antimicrobial substances with their saliva to reduce the risk of bacterial or fungal infection'.
"This is the first real, quantitative, scientific study in that sense, which really quantifies the value of that behaviour", he said. The scientists detailed their findings online February 14 in the journal Proceedings of the Royal Society B.
The African Matabele ants are even willing to sacrifice themselves, researchers noticed. Such feeding episodes, usually undertaken in groups of 300-400 ants, mostly end up with termites being killed and hauled back on to the ants' nest to be eaten.More news: Google raises price of YouTube TV; adds Turner Network, sports shows
"[Matabele ants] have a very defensive prey, capable of inflicting injuries", said Dr Frank.
Getting medical treatment meant injured ants were 70 per cent more likely to survive than those left untended. When help arrives, the injured ants tuck in their legs so they can more easily be carried back to the nest.
Frank said it's possible that other ant species also exhibit the same behaviors. However, they are not immortal. "But we didn't know what was going on inside the nest", he said.
The new research focused on what happens to the injured back in the nest.
Injury to an ant's limb (L) and a similar wound one hour after treatment. By licking the injured ants' severed legs, the healthy ants treat the wounds and save lives. "The other ant grabs it with its mandibles".More news: Arizona State University creates cancer-fighting nanorobots
The ants use their mouthparts to "lick" the wounds of their fellow soldiers. Frank showed that coating dead ants in pheromone summoned helpers, but the ants soon moved on when their fallen comrades failed to tuck into the right position.
Any uninjured ant seems capable of providing the licking treatment - there's no indication of dedicated ant "medics", Frank said - but it's not yet clear whether the treatment prevents infections or actively treats them.
Another major finding of the study was that Matabele ants won't just save any injured nestmate.
"Heavily injured ants (loss of five extremities) were not rescued or treated; this was regulated not by the helper but by the unresponsiveness of the injured ant", said Dr Erik Frank, from Julius-Maximilians University in Wurzburg.
He said the insects appeared to have some sort of "triage" system, where ants decided in the field which individuals were able to be saved.More news: Boris Johnson's big idea on Brexit is just preposterous
"I am always amazed and in awe of the behavioral complexities ant societies are able to show without any type of central organization or consciousness. [They were] basically only rescuing the ones that were worth saving".