BY THE OPTIMIST DAILY EDITORIAL TEAM
From building intricate nests to performing life-saving surgeries, Florida carpenter ants (Camponotus floridanus) are pushing the boundaries of insect behavior. These amazing ants have been seen cleaning and even amputating the limbs of their injured nestmates, demonstrating an extraordinary sort of medical care in the animal kingdom.
Florida carpenter ants take wound care to another level
An international team of academics recently published a paper in Current Biology that dives into the ants’ unique medical talents. Lead author Erik Frank, a behavioral ecologist at the University of Würzburg, states, “When we’re talking about amputation behavior, this is literally the only case in which a sophisticated and systematic amputation of an individual by another member of its species occurs in the animal kingdom.”
Carpenter ants do two types of mechanical wound care: cleaning wounds with their mouthparts and conducting entire leg amputations if needed. Unlike other ants, that use antibacterial substances from specific glands, carpenter ants use solely mechanical means.
Precision in treatment
The researchers thoroughly investigated how these ants assess and treat various types of injury. They identified two types of wounds: femur lacerations and tibia lacerations. Femur injuries were often treated with an initial cleaning and then amputation of the leg, whereas tibia injuries were treated with only cleaning. This targeted strategy greatly increased survival rates. As Frank explains: “…femur injuries, where they always amputated the leg, had a success rate around 90 percent or 95 percent. And for the tibia, where they did not amputate, it still achieved about the survival rate of 75 percent.” In comparison, untreated femoral and tibial injuries had survival rates of 40 percent and 15 percent respectively.
Understanding the medical mechanics
The study looked into why ants choose different treatments for varying injuries. Injuries to the femur, which is mostly made up of muscle tissue, are important for blood pumping. Damage to this area reduces blood circulation and increases the risk of infection. Tibia injuries have a less severe impact on blood flow because they involve less muscle tissue. Surprisingly, the researchers discovered that amputating tibia injuries soon was critical, as delayed amputations resulted in increased mortality.
“It took a minimum of 40 minutes for an ant-assisted amputation. In cases of an injury to the tibia, it was shown that not amputating the leg immediately post-infection meant the ant would die,” Frank notes. Laurent Keller, senior author and evolutionary biologist at the University of Lausanne, says, “Because they are unable to cut the leg sufficiently quickly to prevent the spread of harmful bacteria, ants try to limit the probability of lethal infection by spending more time cleaning the tibia wound.”
Innate medical expertise
The findings show ants’ natural capacity to assess and repair damage. “The fact that the ants are able to diagnose a wound, see if it’s infected or sterile, and treat it accordingly over long periods of time by other individuals — the only medical system that can rival that would be the human one,” Frank said.
Keller underscores the natural basis of these behaviors, stating, “It’s really all innate behavior. Ant behaviors change based on the age of an individual, but there is very little evidence of any learning.”
Future study
The researchers are now looking at whether other species of carpenter ants that lack the antimicrobial gland undertake comparable amputations. This ongoing study could shed light on the evolution of medical practices in ants, as well as raise questions about how these social insects perceive pain.
According to Frank. “When you look at the videos where you have the ant presenting the injured leg and letting the other one bite off completely voluntarily, and then present the newly made wound so another one can finish [the] cleaning process — this level of innate cooperation to me is quite striking.”
The study, “Wound-dependent leg amputations to combat infections in an ant society,” continues to excite academics and enthusiasts alike, revealing light on the complex and fascinating world of Florida carpenter ants.
