A new study published Tuesday (2) has found that ants have a habit of amputating the injured limbs of other ants in the same nest to ensure their survival. The discovery was reported by researchers at the University of Würzburg in Bavaria, Germany, and published in the scientific journal Current Biology.
According to the studythe Florida carpenter ants (Camponotus floridanus) amputate the limbs of ants of the same species as a precautionary measure to prevent life-threatening infections from spreading through the insect’s body.
This species of ant is found predominantly in the southeastern United States. They are reddish-brown in color and relatively large, measuring 1.5 centimeters in length. They usually build nests in rotten wood and defend their home against rival ant colonies, in combats that increase the risk of injury.
The researchers chose to study this species of ant because it does not have a metapleural gland. In other species, this gland produces a secretion that acts as an antibiotic. The aim of the study was to understand how carpenter ants protect themselves against infections.
To do this, the team analyzed video footage of the ant colonies. They then inflicted thigh (or femur) injuries and induced infections on 72 carpenter ants. Half of the ants received thigh amputations performed by the researchers, while the others were used as controls.
The mortality rate of the amputated ants was 90% lower compared to the control group, which suggests that these procedures are successful in preventing the spread of infection. Despite the loss of one of their six legs, these insects are able to resume their tasks in the nest.
Amputations are only performed on injured thighs
The researchers found that the ants only performed amputations if the leg wounds were on the thigh, regardless of whether the wounds were sterile or infected with bacteria. On the other hand, if the wounds were located on the lower leg (tibia), amputations were not performed.
In this second case, the care is carried out in a different way: the ants lick the wounds intensely, possibly as a mechanical way of removing the bacteria. According to the researchers, this mechanism is relatively successful, with a survival rate of 75%.
To understand whether ants could also amputate the lower part of an injured leg, the researchers decided to amputate this region of the ants analyzed in the study that were injured and infected by bacteria. According to the study, the survival rate after the procedure was only 20%.
According to the researchers, there is a possible explanation for this difference: there are many muscles in the ants’ thighs whose activity ensures the circulation of hemolymph, the ants’ “blood”.
“Thigh injuries damage the muscles and make circulation difficult,” explains Erik Frank from the JMU Biocentre in a statement. “Because blood flow is reduced, bacteria cannot leave the wound and enter the body as quickly. In this case, amputation is worthwhile: if action is taken quickly, there is a good chance that the body will still be free of bacteria.”
On the other hand, there are no muscles in the lower leg that are relevant to the circulation of hemolymph. If this region is injured, bacteria enter the body more quickly. In this case, the time available for a successful amputation is shorter and the chance of survival is slim. “This is exactly what ants seem to ‘know’, to put it in human terms,” says the biologist.
“Our study proves for the first time that animals also use prophylactic amputations in the course of wound treatment. And it shows that ants orient the treatment to the type of wound,” adds Laurent Keller, one of the study leaders.
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Source: CNN Brasil
Charles Grill is a tech-savvy writer with over 3 years of experience in the field. He writes on a variety of technology-related topics and has a strong focus on the latest advancements in the industry. He is connected with several online news websites and is currently contributing to a technology-focused platform.
