Male production in parachartergus colobopterus, a neotropical, swarm-founding wasp

Studies of within-colony genetic conflicts have revealed that worker interests sometimes prevail even when they conflict with the queens' interests. Male production is one area where worker's and queens' interests may conflict. A worker is most closely related to her own sons; however, queens often monopolize male production even when outnumbered by the workers. A possible explanation is that workers prevent each other from reproducing when they are more highly related to queen's sons than to other worker's sons. We investigated male production in Parachartergus colobopterus, using DNA microsatellite loci to determine withincolony relatedness and who produced the males. Males were only produced in colonies where collective worker interests and queen interests both favored queens' sons. Analyses of the male genotypes showed that males were produced by the queens. Queen production of males could also be favored if worker reproduction reduced colony efficiency. This is an example of a situation where potential within-colony conflict is resolved by limiting male production to those colonies where the genetic interests of workers collectively, queens, and the interests of colony efficiency coincide. If this kind of conflict resolution is general, withincolony conflict may have played a larger role in social evolution than is currently apparent.