The Effect of Age on Cooperative Behaviours and Use of Social Information in Meerkats (Suricata suricatta)

Abstract

In cooperatively breeding vertebrates, where subordinate helpers assist in the rearing of offspring produced by dominant breeders, there is variation in the contributions of group members to different tasks. Age can influence the cooperative contributions of helpers, but it is unknown how this shapes activity budgets and behavioural trade-offs. Inter-individual variation in cooperative acts may also influence the response of groupmates to such activities, with the use of social information likely to depend on caller reliability, but previous research has mainly focused on alarm calls. We used natural observations to determine if relative age affects contributions to cooperative digging and sentinel behaviour, time spent foraging and the foraging–vigilance trade-off in subordinate meerkats (Suricata suricatta). With a playback experiment, we examined if the relative age of subordinate group members affects the behavioural decisions of foragers. We found that older helpers spent more time on sentinel duty but not digging, less time foraging (particularly in the case of males) and more time vigilant than younger subordinates. Additionally, we demonstrated that age affects how foragers respond to calming sentinel calls: they exhibited less vigilance when hearing calls from an older individual compared to a younger sentinel. Together, these results highlight that age determines behavioural activity budgets and that sentinel calls are assessed on information quality to optimise the foraging–vigilance trade-off.

Date of Award	13 Dec 2024
Original language	English
Awarding Institution	University of Bristol
Supervisor	Andrew N Radford (Supervisor)