Ants have been observed rescuing their injured friends from the field of battle.
African Matabele warring ants displayed heroism by heading back into risky situations – such as termite foraging sites – to carry wounded ants to safety and even treat their wounds.
The extraordinary human-like behaviour is believed to be unique in the animal kingdom.
It results in a dramatic reduction in casualty rates, with scientists discovering that help from the ‘medic’ ants cut the death rate of injured ants from 80% to just 10%.
The African Matabele ants are even willing to sacrifice themselves, researchers noticed.
The ants that were badly injured, too far gone to save, refused to co-operate with their helpers.
German researchers made the discovery after studying violent clashes between the ants and termites in Comoe National Park, Cote d’Ivoire.
The team led by Dr Erik Frank, from Julius-Maximilians University in Wurzburg, wrote in the journal Proceedings of the Royal Society B: ‘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.
‘We show organised social wound treatment in insects through a multifaceted help system focused on injured individuals. This was not only limited to selective rescuing of lightly injured individuals by carrying them back (thus reducing predation risk), but, moreover, included a differentiated treatment inside the nest.’
Marching in long files of 200 to 600 insects, colonies of Matabele ants were found to launch their termite raids two to four times per day.
Numerous worker termites were killed and hauled back to the ants’ nests, to be eaten. Often, the ants met strong resistance as the termites used their powerful jaws to slice through enemy limbs.
Injured ants secreted a chemical pheromone scent signal that compelled other soldiers to come to their aid.
Casualties were carried back to the nest, where their open wounds were ‘treated’ by intensive licking, often for several minutes, the scientists learned.
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.’
While slightly injured ants kept still and even pulled in their remaining limbs to facilitate being carried, their badly wounded comrades struggled and lashed out wildly.
‘They simply don’t cooperate with the helpers and are left behind as a result,’ Dr Frank added.
H/T: Science Advances.