The Matabele ants risk their lives in battle every day. Two to four times a day they leave their nests and proceed in columns of about five hundred ants to fight battles with termites at their termite nests. Fierce battles take place and dead termites are carried back home as food. Although the ants are very big the termites can inflict devastating injury as they hack off limbs with their powerful jaws. A wounded ant secretes a chemical substance that works as an SOS call to the other ants. These put the injured ant on their backs and off they go home where nurse ants treat the wounds by covering them with saliva that contains a potent antiseptic and antifungal chemical that block all infection. The wounded ant soon recovers and then goes into rehab where it learns to walk and run with one, two or three legs less. A week later it is ready to partake in new incursions. If the ant is too badly injured to be taken back home for treatment it is left to die on the battlefield. But, who decides how serious the wounds are. It is the wounded ant itself that decides. If too serious, with its remaining energy it kicks and wrestles so preventing the other ants to assist it. If instead the wounds are not serious it stays motionless and crouched so helping its mates do their job. It might happen that an ant gets injured even lightly while on the way to invade a termite nest. In this case there is no assistance as this would mean another ant must leave the column to help the injured one get back home but this could endanger both as they would now be alone in front of predators. The injured ant could be taken to the termite nest and at the end of the battle taken back home but again this would be dangerous as the entire column would have to move at reduced speed so giving up the surprise effect. Whatever happens, it is always the injured ant that decides whether to receive help or not for the general good. The rescuers instead help any ant that secretes the chemical, even perfectly healthy ants on which the chemical has been sprayed experimentally.