BUG SPRAY: Worker ants tear apart and spray acid on a pupa in an act of destructive disinfection.CHRIS PULL
In a petri dish, three Lasius neglectus worker ants surround a cocooned pupa from their own colony’s brood. Tearing into it with their mandibles, the ants remove the pupa from the cocoon, perforate its cuticle, and rip its body apart, dividing it between them. Finally, the workers apply formic acid from their mouths to the eviscerated pupa, leaving behind a heap of crumpled remains.
This is no random act of violence. According to Chris Pull, an evolutionary biologist at Royal Holloway, University of London, these ants were engaging in destructive disinfection, killing the pupa along with the ant-killing fungus, Metarhizium brunneum, that had infected it. The behavior evolved in social insects such as ants, honeybees, and termites to protect colonies from infected individuals, says Pull, ...
