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Temporal polyethism is used as a gauge for behavioral development in an arid-land ant. A worker is considered mature when it spends more than half of its time outside the nest and no longer tends either brood or queen. When the oldest workers and remaining age-groups were removed, recently eclosed callows matured, that is, developed behaviorally, in one third of the baseline time. When all age-groups were removed except the oldest, these outside workers reverted to tending brood and queen inside the nest, although they had not been observed touching either for 4–6 months. Callows in contact with the queen alone were rarely stimulated to leave the nest; both chemotactile and olfactory contact with larvae elicited some foraging and increased time spent outside by callows. Stimulation from recently eclosed callows elicited considerable foraging response from callows that had eclosed several days earlier. It is hypothesized that stimulation from eclosing callows accelerates the process of behavioral development characteristic of the species and that stimulation from larvae stabilizes the gains made during this acceleration into mature adult behavior.

Social regulation of behavioral development in insects had been ignored for many years. While researchers were demonstrating the behavioral plasticity of vertebrates, behavior in insects was largely seen as developing according to a rigid, genetically determined plan, chained to biological maturation. However, some studies correlating behavioral development with physiology have been done. Temporal polyethism, the division of labor according to age, in honeybees has been correlated with the reduction of mandibular and wax glands that occurs concomitantly with the worker bees' progress through various age-related tasks both within and outside the nest (King, 1933). Free (1965) demonstrated social regulation of proportions of worker bees performing tasks under crowded conditions and reviewed the work of other researchers showing that the removal of younger age-groups is correlated with a regeneration of wax glands and hypopharyngeal glands in...