Injured ants receive different treatments based on injury location

Worker ants of the species Camponotus floridanus treat leg injuries differently depending on where the wound occurs. If the injury is at the femur, the upper part of the leg, the ants amputate the limb. If the injury is at the tibia, the lower part of the leg, they only clean the wound with their mouths.

Amputation improves survival rates dramatically

According to a study by Erik Frank and his team, amputating a femur wound increases the survival rate of injured ants from less than 40% to over 90%. In contrast, cleaning a tibia wound raises survival to about 75%, showing that the treatment location significantly affects the outcome.

Ants lack a chemical disinfectant gland

The species Camponotus floridanus has lost its metapleural gland, which in other ants produces antimicrobial substances to disinfect wounds. Without this chemical tool, the ants have evolved a mechanical alternative: collective surgery to manage infections.

Wound location affects infection speed

The location of the injury influences how quickly pathogens spread. Injuries at the tibia, where hemolymph—blood-like fluid—flows faster, allow bacteria to reach the rest of the body within five minutes. This makes amputation too late to be effective, so the ants only clean the wound.

Amputation is a time-consuming process

Amputating a femur wound requires the ants to bite repeatedly for at least 40 minutes, and sometimes over three hours. This slow process allows enough time to prevent the infection from spreading, making the surgery effective. In controlled experiments, this behavior was observed in 76% of femur injury cases.

Collective behavior without central control

The study published in Current Biology highlights the precision of this collective behavior. The ants act without a central brain or verbal communication, demonstrating a remarkable ability to diagnose and treat wounds based on their location. This behavior challenges previous assumptions about insect medical practices.

Research extends to other ant species

Erik Frank’s team previously studied Megaponera analis, another ant species that uses antimicrobial compounds to treat wounds. Now, they are investigating whether similar surgical behavior is present in other Camponotus species. This research may change how we understand collective medicine in social insects.