Fast and accurate decisions through collective vigilance in fish shoals
2011 (English)In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 108, no 6, 2312-2315 p.Article in journal (Refereed) Published
Although it has been suggested that large animal groups should make better decisions than smaller groups, there are few empirical demonstrations of this phenomenon and still fewer explanations of the how these improvements may be made. Here we show that both speed and accuracy of decision making increase with group size in fish shoals under predation threat. We examined two plausible mechanisms for this improvement: first, that groups are guided by a small proportion of high-quality decision makers and, second, that group members use self-organized division of vigilance. Repeated testing of individuals showed no evidence of different decision-making abilities between individual fish. Instead, we suggest that shoals achieve greater decision-making efficiencies through division of labor combined with social information transfer. Our results should prompt reconsideration of how we view cooperation in animal groups with fluid membership.
Place, publisher, year, edition, pages
2011. Vol. 108, no 6, 2312-2315 p.
swarm intelligence, collective decision-making, sociality
IdentifiersURN: urn:nbn:se:uu:diva-149568DOI: 10.1073/pnas.1007102108ISI: 000287084500028PubMedID: 21262802OAI: oai:DiVA.org:uu-149568DiVA: diva2:405189