Chapter 77 - Division of Labor in Insect Societies

Abstract

This chapter discusses division of labor in insect societies. Division of labor is one of the defining characteristics of the most extreme form of sociality in the animal kingdom, eusociality. Eusociality is defined by three traits: Cooperative care of young by members of the same colony; an overlap of at least two generations of adults in the same colony; and division of labor for reproduction, with sterile individuals working on behalf of fecund colony members. Females dominate the functioning of insect societies in which males play more diverse roles than in hymenopteran societies. There are two types of females in an insect society, queens and workers. Queens specialize in reproduction and may lay up to several thousand worker eggs per day. Workers are either completely or partially sterile, engage in little, if any, personal reproduction, and perform all tasks related to colony growth and maintenance. There is also a division of labor among the workers for tasks related to colony growth and maintenance. Colony division of labor, although highly structured, also shows great plasticity. Colonies respond to changing needs by adjusting the ratios of individual workers engaged in different tasks. There is plasticity in age-related division of labor, with workers being able to respond to changes in colony age demography with accelerated, retarded, or reversed behavioral development.