Skip to main content

Research Repository

Advanced Search

Consensus decision making in human crowds

Dyer, John R. G.; Ioannou, Christos C.; Morrell, Lesley J.; Croft, Darren P.; Couzin, Iain D.; Dyer, John R.G.; Waters, Dean A.; Krause, Jens; Morrell, Lesley


John R. G. Dyer

Christos C. Ioannou

Darren P. Croft

Iain D. Couzin

John R.G. Dyer

Dean A. Waters

Jens Krause


In groups of animals only a small proportion of individuals may possess particular information, such as a migration route or the direction to a resource. Individuals may differ in preferred direction resulting in conflicts of interest and, therefore, consensus decisions may have to be made to prevent the group from splitting. Recent theoretical work has shown how leadership and consensus decision making can occur without active signalling or individual recognition. Here we test these predictions experimentally using humans. We found that a small informed minority could guide a group of naive individuals to a target without verbal communication or obvious signalling. Both the time to target and deviation from target were decreased by the presence of informed individuals. When conflicting directional information was given to different group members, the time taken to reach the target was not significantly increased; suggesting that consensus decision making in conflict situations is possible, and highly efficient. Where there was imbalance in the number of informed individuals with conflicting information, the majority dictated group direction. Our results also suggest that the spatial starting position of informed individuals influences group motion, which has implications in terms of crowd control and planning for evacuations.


Dyer, J. R. G., Ioannou, C. C., Morrell, L. J., Croft, D. P., Couzin, I. D., Waters, D. A., & Krause, J. (2008). Consensus decision making in human crowds. Animal behaviour, 75(2), 461-470.

Journal Article Type Article
Acceptance Date May 30, 2007
Online Publication Date Oct 18, 2007
Publication Date 2008-02
Print ISSN 0003-3472
Publisher Elsevier
Peer Reviewed Peer Reviewed
Volume 75
Issue 2
Pages 461-470
Keywords Collective behaviour; Consensus decision making; Human crowd; Information transfer; Leadership
Public URL
Publisher URL