Ritualized combat and intercolony communication in ants

Abstract

Colonies of the honey ant Myrmecocystus mimicus engage each other in elaborate display tournaments. Hundreds of ants are often involved, but almost no physical fights occur. Instead, opponents confront one another in highly aggressive displays, during which they walk on stilt legs while raising their abdomens and heads. The tournaments serve as temporary spatial borders within which food gathering occurs. In this study we develop the hypothesis that tournaments are a mechanism of intercolony communication, which opposing colonies use to gauge each other's strength. Models are proposed for the behaviorial procedures that seem most likely to underly this capacity. For the first time it is possible to ascertain and compare the properties of such models in relation to a body of test data. It appears probable to us that intercolony communication in this species of ant may depend upon a novel capacity for integrative information harvesting by individual workers.