Humans are no longer the only species on Earth that can perform life-saving surgery. A new study says that certain species of ants can not only detect injuries to colony members, but also decide whether amputation is necessary to save the ants’ lives.
Unlike humans, ants do not need to go to medical school beforehand, and each ant in the colony is capable of performing these seemingly basic medical interventions to ensure the survival of another ant.
Last year, scientists from the University of Würzburg in Germany observed that an African species of ant, Megaponera analisthey can treat infected wounds with antimicrobial substances they produce in their glands. For the new experiment, the same scientists chose a different species of ant: the Florida carpenter ant (Camponotus floridanus).
The researchers looked at two types of wounds located in different places on the ants’ legs: the femur and the tibia. They also infected the wounds with bacteria that would otherwise kill the ant that sustained the injury.
The researchers found that the ants were able to detect that one of their nestmates had suffered an injury and was potentially infected. Depending on the location of the wound, the ants that detected the injury would then decide on the correct course of action.
A wound to the femur would lead to amputation. On average, ants would spend roughly 40 minutes biting an injured person’s leg. However, if the injury occurred lower down on the tibia, the ants would choose to just clean the wound rather than sever the limb.
“When we talk about amputation behavior, this is literally the only case where sophisticated and systematic amputation of an individual by another member of its species occurs in the animal kingdom,” study author Erik Frank said in a statement. Living science.
The researchers observed that amputating a limb suffering from an infected femoral wound would significantly increase the patient’s chances of survival. Ants amputated 21 of 24 ants with femur injuries and all 21 survived. The three who did not undergo surgery died. It is not clear why three of these Florida carpenter ads did not undergo surgery.
In comparison, none of the 24 ants with tibial injuries had their limbs amputated. The researchers realized that the ants already knew that cutting off the leg of an infected nest with a tibial injury would not work.
Laboratory experiments have shown that amputations of ants with tibial injuries must be performed soon after the accident to reduce mortality.
While the ants know how to perform the surgery, it still takes them 40 minutes to amputate a leg. By then, the infection would have spread to the body of the infected nestling and amputation would be unnecessary. This certainly mimics the approach of people deciding whether surgery makes sense.
But why would thigh injuries benefit from amputation surgery in ants compared to tibial wounds? The researchers speculated that the muscles surrounding the femur have a larger surface area than the muscles around the tibia.
When the muscles are injured, the blood flow in the femur section can slow down. Therefore, it may take longer for the bacteria to reach the rest of the body. The other ants have time to act and amputate the entire leg.
A wound at the level of the tibia would not affect circulation in a similar way. Therefore, the bacteria would spread faster. The ants would not have a chance to get rid of the injured limb before it is too late, so they resort to local treatment of the wound.
Experiments showed that the topical treatment was able to reduce the bacterial load in ants with tibial injuries. However, the pathogen load was significantly lower in ants with femur injuries and amputated limbs.
The results are incredible and show the advanced behavior of ant societies in treating their own subsequent accidents and infections. The entire study can be found in Contemporary Biologyaccompanied by videos showing ants tending to an injured nestmate, including performing surgery.