Two carpenter ants, Camponotus fellah, are seen in this undated photograph in a laboratory at the University of Lausanne in Switzerland. The ant on the right is caring for the leg wound of the other ant. Bart Zijlstra/Handout via REUTERS
These ants were observed treating injured limbs of nestmates either by cleaning the wound using their mouthparts or by amputation through biting off the damaged limb. The choice of care depended on the injury's location. When it was further up the leg, they always amputated. When it was further down, they never amputated.
The researchers studied injuries to the upper part of the leg, the femur, and the lower part, the tibia. Such injuries are commonly found in wild ants of various species, sustained in fights, while hunting or through predation by other animals."They decide between amputating the leg or spending more time caring for the wound. How they decide this, we do not know. But we do know why the treatment differs," Frank said.
In either case, the ants first cleaned the wound, likely applying secretions from glands in the mouth while also probably sucking out infected and dirty hemolymph. The amputation process itself takes at least 40 minutes and sometimes more than three hours, with constant biting at the shoulder.