Worker queens? Effect of methoprene on behavioral plasticity in queens of the little fire ant Wasmannia auropunctata

One of the most important traits of social insects, such as ants, is reproductive division of labor, where queens lay eggs and sterile worker castes perform nest duties including brood care and foraging. The queens of the little fire ant Wasmannia auropunctata, a monomorphic species with age related division of labor, has recently been found to have behavioral plasticity; when nurses are absent from the colony queens perform nursing tasks including brood tending and nest cleaning. We evaluated the effects of methoprene, a juvenile hormone (JH) analog, on these behaviors. When we gave the queens a dose of methoprene we found that methoprene promotes queens to lay eggs instead of nursing or foraging. With this data we can infer that the behavioral plasticity that these queens have should be related to changes in hormone levels, where queens who are doing non-typical tasks will have a lower titers of JH in contrast of laying queens who will have a high titer of JH. The results of this study may shed light on the factors contributing to behavioral plasticity in this ant. Moreover, it also contributes to our understanding of the relationship between hormones and division of labor.