Telling Your Friends Where the Goodies are – Recruitment Signals for Food and Habitat

Abstract

Social organisms have evolved a myriad of mechanisms to recruit others to food sources found. Such recruitment is particularly profitable if the source is plentiful and ephemeral, or too large to be transported by a single individual. Ants, termites and some social bees and wasps use pheromones as recruitment signals. Such signals are excreted by individuals that have located a profitable food source, and are deposited on the ground as a continuous trail (ants and termites), left on prominent vegetation (stingless bees), or at the actual food source (some bees and wasps). When recruitment signals are left in the open, others can also eavesdrop on the information. Some social insects therefore have moved their recruitment signaling inside the nest. The most primitive form of in-house recruitment are probably the excitatory movements performed by returning foragers, who often also carry the odor of the food source on them. The most sophisticated form of recruitment is found in honeybees, where the so-called waggle dance conveys directional and distance information to nestmates. Many social insects further use recruitment signals when selecting a new home, but information on nest site selection is scarce, mainly restricted to honeybees and some species of ants.