Almost royal: incomplete suppression of host worker ovarian development by a social parasite wasp

作者：Cini Alessandro^*; Nieri Rachele; Dapporto Leonardo; Monnin Thibaud; Cervo Rita

来源：Behavioral Ecology and Sociobiology, 2014, 68(3): 467-475.

DOI：10.1007/s00265-013-1661-z

• Reproductive skew
• Reproductive decision
• Brood parasitism
• Intracolonial conflicts
• Paper wasps
• Polistes sulcifer
• Polistes dominula

Insect social parasites, like other parasites, may benefit from inhibiting their host from reproducing (complete or partial parasitic castration) because they can then exploit more of the host's resources for their own reproduction. In particular, social parasites that kill or expel the host queen need to prevent host workers from reproducing; this is a common worker response to the absence of their queen. Indeed, host workers would benefit from detecting the presence of the parasite and investing in direct and indirect fitness. Studying whether and how social parasites control host worker reproduction can provide information about the degree of integration of the parasite in the host colony and help identify factors regulating workers' reproductive decisions in social insects. We investigated whether the paper wasp social parasite, Polistes sulcifer, suppresses Polistes dominula (host) worker reproduction as efficiently as the dominant host female does in queen-right colonies by comparing worker reproductive efforts in parasitized and non-parasitized (control) colonies. Our results show that 6 weeks after usurpation of their colony by the social parasite, parasitized workers (1) had more developed ovaries than control workers and (2) laid more eggs as soon as the opportunity arose. This reproductive readiness of parasitized workers was not apparent 2 weeks after colony usurpation. This suggests that P. dominula workers have evolved means to react to social parasitism, as occurs in some ants, and that the parasite has only limited control over host reproduction.

• 出版日期2014-3