Influence of age polyethism on longevity of workers in social insects

Age polyethism is widespread among social insects and, as a rule, safe tasks are performed by workers earlier in life than are risky ones. Mathematical models were used to compare expected longevity of workers in colonies with and without age polyethism. The results of the models suggest that if aging does not depend on activity then age polyethism is profitable when safer tasks are performed earlier in life. If, however, aging depends on activity, age polyethism is profitable when safer tasks are performed earlier in life and if they are associated with higher aging-related mortality. On the other hand, age polyethism is not profitable if safer tasks are performed later in life, and if they are associated with lower aging-related mortality. Furthermore, if there is no aging, then age polyethism does not bring any benefits.