“…in birth rates, death rates, and dispersal rates) and developmental traits cause the force of natural selection to change with age [34], which should influence age-based changes in social behaviour by altering who is available for interaction, including similarity to others in traits or states (their level of homophily), as well as familiarity and relatedness of group members. It has been shown, for instance, that similarity in age [13,151,153] and shared experience [154] [156], which, in some specific contexts, is suggested to play an important role in selecting for late-life helping behaviour, such as the cessation of females' reproduction in favour of promoting their offspring's reproductive success [42,157]. However, in addition to affecting decisions 'to breed' or 'not to breed' [156], changes in local relatedness might also affect the rates and distribution of affiliative or agonistic interactions.…”