Believe it or not, ants can perform life-saving surgery. What we know – Firstpost

Humans are not the species that can perform amputations to save lives. A new study conducted on carpenter ants in Florida shows that they bite off the limbs of nestmates in an attempt to save the lives of others. According to new research, 90 to 95 percent of ants that receive amputations make it through the process and continue with their tasks inside the nest just fine, despite losing a leg, researchers found.

The study was published Tuesday in the journal Current Biology, observed that ants treated the limbs of nestmates by either cleaning the wound using their mouthparts or amputating them by biting the injured limb. The choice of care depended on the location of the injury.

Study findings

“In this study, we describe for the first time how a non-human animal uses the amputations of another individual to save their life,” said entomologist Erik Frank from the University of Würzburg in Germany, lead author of the research published in on Tuesday at journal Current Biology.

“I am confident that we can safely say that the ant ‘medical system’ for caring for the injured is the most sophisticated in the animal kingdom, rivaled only by our own,” Frank added. This species nests in rotting wood and strongly defends its home against rival ant colonies. “If fights break out, there is a risk of injury,” he added.

The researchers studied injuries to the upper part of the leg, the femur, and the lower part, the tibia. Such injuries are usually found in wild ants of various species, sustained in fights, during hunting or during predation by other animals. The ants were observed under laboratory conditions.

“They decide between amputating the leg or spending more time tending to the wound. How they decide this, we don’t know. But we know why treatment varies,” Frank said. It has to do with the flow of hemolymph, the bluish-green fluid equivalent to blood in most invertebrates.

Treatment of injuries

“Injuries further down the leg have an increased flow of hemolymph, meaning that pathogens already enter the body after just five minutes, making amputations useless by the time they can be performed. Injuries further up the leg have a much slower flow of hemolymph, allowing enough time for timely and effective amputations,” Frank said.

In each case, the ants first cleaned the wound, likely by applying secretions from glands in their mouths, while possibly sucking up the infected and contaminated hemolymph. The amputation process itself takes at least 40 minutes and sometimes more than three hours, with constant biting on the shoulder.

With amputations following an upper leg injury, the documented survival rate was about 90-95 percent, compared to about 40 percent for untreated injuries. For lower leg injuries in which only debridement was performed, the survival rate was about 75 percent, compared to about 15 percent for unattended injuries.

Wound care has been documented in other ant species that apply an effective antibiotic gland secretion to injured nestmates. This species lacks that gland. Ants, which have six legs, are fully functional after losing one. Female ants were observed doing this behavior.

“All worker ants are female. Males play only a small role in ant colonies – they mate once with the queen and then they die,” Frank said.

Reason for amputations

“This is an interesting question, and it calls into question our current definitions of empathy, at least to some extent. “I don’t think ants are what we would call ‘compassionate,'” Frank said.

“There is a very simple evolutionary reason for caring for the injured. It saves resources. If I can rehabilitate a worker with relatively little effort, who will then become an active productive member of the colony again, there is a very high value in doing so. At the same time, if an individual is injured too badly, the ants will not take care of him, but instead leave him behind to die,” Frank added.

With data from Reuters