A new study on ants has revealed that ants can identify their dead nestmates, and they carry their dead nestmates out of their nests before the dead ants infect the whole colony with their pathogens. According to study, ants identify dead ants with the help of a chemical.    

The study, conducted by Dong-Hwan Choe and team of entomologists from University of California, has found that the alive ants produce chemicals that give signals of their vitality, but signals quickly vanish on death. The alive ants are able to identify the dead ants from life signals released by chemicals.

According to entomologists, ants differentiate between their alive and dead nestmates on the basis of two chemicals – dolichodial and iridomyrmecin – produced by the ants. The two chemicals prevent ants from carrying their alive nestmates off their nests, but signal the insets for Necrophoresis – the removal of their dead nestmates out of their nests. The disposal squads of ant colony come into action within one hour of the death of any member.

The study published in the US journal 'Proceedings of the National Academy of Sciences' has articulated that the two chemicals vanish away quickly after death. The strength of the chemicals drops to below half-strength in just 10 minutes. The two chemicals serve as signals to repress or activate necrophoric behavior in workers.