Foundress number, but not queen size or boldness, predicts colony life-history in wild paper wasps

Abstract

Colonies of social insects exhibit a spectacular variety of life histories. Here, we documented the degree of variation in colony life-history traits, mostly related to productivity, in two species of wild paper wasps. We then tested for associations between colony life-history traits to look for evidence of trade-offs vs. a life-history productivity syndrome (i.e. all colony performance metrics are positively correlated) and examined whether differences in the individual behavioural tendencies of foundresses (Polistes metricus) or the number of cofoundresses (Polistes fuscatus) influenced colony life history. The majority of our measures of colony life history were positively related, indicating no obvious resource allocation trade-offs. Instead, the positive association of traits into a productivity syndrome appears to be driven by differences in queen or microhabitat quality. Productivity syndrome structure differed only marginally between species. Queen boldness and body size were not associated with colony life history in P. metricus. Colonies initiated by multiple P. fuscatus were more productive, and this advantage was approximately proportional to the number of cofoundresses. These findings demonstrate that colony life-history traits can be associated much like individual life-history traits, and the associations seen here convey that differences in overall productivity drive between-colony differences in life history.