First published 30 July 2014
Exploring conditions that select for the evolution of cooperative group foraging
Patrick B. Haley, Randal S. Olson, Fred C. Dyer, and Christoph Adami
Many prey choose to live, forage, and reproduce in groups --this is one of the most readily-observed phenomena in biology. Group living is potentially costly (because of competitive interactions among other reasons), and the benefits that outweigh these costs are difficult to understand, as they may interact in complicated ways (Krause and Ruxton, 2002). Collective vigilance is one oft-cited benefit of grouping behaviors. This claim relies on the principle that at each moment in time prey must make a choice between two mutually exclusive actions: foraging for food or being vigilant to look for predators. Group foraging potentially allows individuals to increase their foraging efficiency--and therefore their fitness -- by sharing the expensive task of looking out for predators. Since isolating such decision-making in biological systems is difficult (particularly on an evolutionary timescale), we use digital organisms to study how this decision is made by groups of prey under the threat of predation.