1. Lima, S. L. & Dill, L. M. Behavioural decisions made under the risk of predation: a review and prospectus. Can. J. Zool. 68, 619–640 (1990).
2. Krause, J. & Ruxton, G. D. Living in Groups (Oxford University Press, 2002).
3. Earley, R. L. & Dugatkin, L. A. Behavior in groups in Evolutionary Behavioural Ecology (eds. Westneat, D. F. & Fox, C. W.) 285–307 (Oxford University Press, 2010).
4. Beauchamp, G. Social Predation: How Group Living Benefits Predators and Prey (Academic Press, 2014).
5. Farabaugh, S. M., Brown, E. D. & Hughes, J. M. Cooperative territorial defense in the Australian magpie, Gymnorhina tibicen (Passeriformes, Cracticidae), a group-living songbird. Ethology 92, 283–292 (1992).