“Worker queens”? Behavioral flexibility, juvenile hormone binding protein and vitellogenin in queens of the little fire ant Wasmannia auropunctata

The little fire ant, a monomorphic species with age related division of labor, has been found to have flexibility of worker division of labor where older ants, that typically forage, return to the nest to perform nursing duties when these are absent. Typically in established colonies queens only perform reproductive tasks. We examined behavior of queens of the little fire ant Wasmannia auropunctata after demographic manipulation. Surprisingly when half of the workers were removed from the colony, queens were observed caring for eggs, larvae and pupae as well as eating outside of the nest, like forager workers. We examined the relationship between different these atypical behaviors of the queens and their juvenile hormone binding protein (JHbp) and vitellogenin (Vg) expression via QRT-PCR method. JHbp and Vg expression decreased when queens were performing worker tasks. We discuss significance of these results for endocrine regulation of behavior and reproduction.