The pace and shape of ant ageing

Ants have been proposed as good models to study ageing and the effects of extrinsic mortality because of their long lifespans and plasticity of ageing within species. We discuss how age-dependent extrinsic mortality might influence queen lifespan, and how the effect of age-independent extrinsic mortality needs further study, accounting for different density-dependence scenarios. Based on a critical review of the available demographic data, we discuss the selective forces underlying ant ageing. We discuss differences and similarities between the life-history strategy of ants and the reproductive strategies iteroparity and semelparity. We consider how late-life fitness gains for the "superorganism" select for a delay of actuarial, and reproductive senescence, and we suggest future research directions.