Ergonomic mechanisms for handling variable amounts of work in colonies of the wasp Ropalidia marginata

Abstract

The mechanisms by which a colony handles varying amounts of work was studied in the primitively eusocial wasp Ropalidia marginata. The number of active workers in the colony, per capita colony work and task generalization of individual workers increased when the amount of colony work was greater. The manner in which these three variables change suggests that a colony shows a graded response to changing amounts of work, whereby the three mechanisms are activated in a hierarchical manner. There was no evidence, however, of any adjustments in the foraged load size as a response mechanism to variable amounts of work in the colony. The implications of these results for the colony size-colony productivity debate are discussed.