Personality and body mass impact social group formation and function in paper wasps.

Many animals devote substantial time, energy and resources to assessing nonmating social partners. However, relatively little is known about how individual characteristics influence the process and outcome of social partner choice. Social partner choice is an important aspect of Polistes fuscatus wasp lives, as nest-founding queens form and dissolve many short-term social relationships before settling down in stable cooperative groups. Here, we asked how personality and body size influence social partner assessment, the specific partners chosen, behaviour within social groups and group offspring production. We evaluated social and nonsocial personality traits (exploration, affiliation, aggression, investigation) and body mass in 75 individually marked queens, then released them in a large naturalistic enclosure where we recorded social partner assessment, nest founding behaviour and behaviour on nests. At the end of the season, we collected nests as a measure of group reproductive output. Exploratory personality had a stronger effect on social behaviour than other personality measures. More exploratory wasps sampled more social partners, joined nests later and spent fewer days as members of stable nests. Less exploratory wasps were more likely to become dominant on nests and were more aggressive after partnerships were established. Larger wasps sampled more potential nest sites, suggesting that sampling induces energetic costs that larger individuals are better able to bear. Among dominant and solitary-nesting wasps, more affiliative wasps built larger nests and more aggressive wasps built smaller nests. We did not find that wasps selected partners based on any measured trait. Overall, our work demonstrates that personality traits play an important role in how social partners are assessed, how social groups are formed, behaviour within established social groups and the success of social groups. Our study also suggests that personality mediates a trade-off between time spent sampling partners and social bond stability. • We evaluated effects of personality and body size on social partner choice in wasps. • More exploratory wasps sampled more social partners and joined nests later. • They spent fewer days in stable groups and were less likely to be dominant on nests. • Body size and social personality had little effect on partner assessment. • Personality may mediate a social assessment–stable social bond trade-off. [ABSTRACT FROM AUTHOR]