Author:

Keywords:

worker reproduction, worker policing, social insects, Vespinae, wasps, dolichovespula sylvestris, queen policing, Science & Technology, Life Sciences & Biomedicine, Behavioral Sciences, Ecology, Zoology, Environmental Sciences & Ecology, social policing, reproductive conflict, vespinae, Dolichovespula sylvestris, APIS-MELLIFERA-CAPENSIS, EUSOCIAL HYMENOPTERA, INSECT SOCIETIES, HONEYBEES APIS, SOCIAL INSECTS, PONERINE ANT, REPRODUCTIVE CONFLICT, DOMINANT WORKERS, STINGLESS BEES, COLONY SIZE, 05 Environmental Sciences, 06 Biological Sciences, 07 Agricultural and Veterinary Sciences, Behavioral Science & Comparative Psychology, 30 Agricultural, veterinary and food sciences, 31 Biological sciences, 41 Environmental sciences

Abstract:

Insect societies are sometimes exploited by workers who reproduce selfishly rather than help to rear the queenrsquos offspring. This causes a conflict-of-interest with the mother queen and, frequently, with the non-reproductive workers as well. One mechanism that can reduce conflict is policing, whereby either the queen or other workers aggress egg-laying workers or destroy worker-laid eggs. Here we present the first direct observations of queen and worker policing in natural, unmanipulated colonies of a social insect, the tree wasp Dolichovespula sylvestris. Worker reproduction was common, with workers producing 50% of all male eggs. However, most worker-laid eggs, 91%, were policed within 1 day, whereas most queen-laid eggs, 96%, remained unharmed. The workers were responsible for 51% of all policing events and the queen for 49%. The workers and mother queen also commonly aggressed ovipositing workers, and successfully prevented them from depositing eggs in 14% and 6% of all attempted ovipositions. Hence, both queen policing and worker policing occur and policing acts via two distinct mechanisms: selective destruction of worker-laid eggs and aggression of ovipositing workers. At a general level, our study shows that both centralized and decentralized control can act together to suppress conflict within social groups.