Colony integration in honey bees: Genetic, endocrine and social control of division of labor

This paper reviews our understanding of the mechanisms that enable adult worker honey bees to show plasticity in age polyethism in response to changing environmental conditions. There are genotypic differences in rate of behavioral development, which predispose individuals to respond to changing conditions in predictable ways. For example, genotypes that have relatively fast rates of behavioral development under more typical conditions are more inclined to show precocious foraging in the absence of foragers of normal age. Juvenile hormone influences rate of behavioral development, and environmentally induced changes in JH titers are thought to underlie changes in age polyethism. Results of recent experiments indicate that changes in the age at onset of foraging caused by changes in colony age demography are at least partially a consequence of social interactions in which older bees inhibit the rate of behavioral development of younger bees. Chemical signals are suspected to feature prominently in these interactions, and preliminary evidence supporting this notion is presented.