The evolution of personally disadvantageous punishment among cofoundresses of the ant Acromyrmex versicolor

Cofoundresses of the desert fungus garden ant Acromyrmex versicolorexhibit a forager specialist who subsumes all foraging risk priorto first worker eclosion (Rissing et al. 1989). In an experimentdesigned to mimic a "cheater" who refuses foraging assignment whenher lot, cofoundresses delayed/failed to replace their forager,often leading to demise of their garden (Rissing et al. 1996). Thecheater on task assignment is harmed, but so too is the punisher,as all will die without a healthy garden. In this paper we studythrough simulation the cofoundress interaction with haploid, asexualgenotypes which either replace a cheater or not (punishment), underboth foundress viscosity (likely for A. versicolor) and randomassortment. We find replacement superior to punishment only whenthere is no foraging risk and cheating is not costly to groupsurvival. Generally, punishment is evolutionarily superior,especially as forager risk increases, under both forms of dispersal.