Curr. Biol. 19, 78–81 (2009)

Ants, like other social creatures, strive to minimize antisocial behaviour by punishing cheaters. For example, fertile worker Aphaenogaster cockerelli ants that could undermine the unity of a colony with a single reproducing queen are attacked by nestmates. Although it has remained unclear how would-be cheats are identified, evidence suggested that variations in the hydrocarbons in ants' cuticles might be involved. Jürgen Liebig of Arizona State University in Tempe and his colleagues show that when A. cockerelli workers in colonies headed up by a queen are manually coated with pentacosane, a hydrocarbon linked with fertility, they are attacked by their nestmates.

Because ant eggs carry distinctive related hydrocarbons that prevent them from being identified and destroyed, cheaters probably cannot suppress their chemical profiles. Thus, hydrocarbons could provide an inherently reliable method to catch cheats.