Duncan, ChrisManser, Marta B.Clutton-Brock, Tim H.2022-07-282022-07-282021-11Duncan, C., Manser, M. B., & Clutton-Brock, T. (2021). Decline and fall: The causes of group failure in cooperatively breeding meerkats. Ecology and Evolution, 11, 14459–14474. https://DOI.org/10.1002/ece3.7655.2045-7758 (online)10.1002/ece3.7655https://repository.up.ac.za/handle/2263/86550Chris Duncan: Conceptualization (equal); Data curation (equal); Formal analysis (lead); Methodology (lead); Writing-original draft (lead); Writing-review & editing (equal). Marta B. Manser: Data curation (equal); Funding acquisition (equal); Project administration (equal); Resources (equal); Writing-review & editing (equal). Tim Clutton-Brock: Conceptualization (equal); Data curation (equal); Funding acquisition (equal); Project administration (equal); Resources (equal); Supervision (equal); Writing-review & editing (equal).In many social vertebrates, variation in group persistence exerts an important effect on individual fitness and population demography. However, few studies have been able to investigate the failure of groups or the causes of the variation in their longevity. We use data from a long-term study of cooperatively breeding meerkats, Suricata suricatta, to investigate the different causes of group failure and the factors that drive these processes. Many newly formed groups failed within a year of formation, and smaller groups were more likely to fail. Groups that bred successfully and increased their size could persist for several years, even decades. Long-lived groups principally failed in association with the development of clinical tuberculosis, Mycobacterium suricattae, a disease that can spread throughout the group and be fatal for group members. Clinical tuberculosis was more likely to occur in groups that had smaller group sizes and that had experienced immigration.en© 2021 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution License.Cooperative breedingGroup failureGroup persistenceGroup sizeSocialityMeerkat (Suricata suricatta)Tuberculosis (TB)Mycobacterium suricattaeArticle