Behavioral Ecology and Sociobiology

, Volume 68, Issue 3, pp 449–456 | Cite as

Humans use social information to adjust their quorum thresholds adaptively in a simulated predator detection experiment

  • Ralf H. J. M. KurversEmail author
  • Max Wolf
  • Jens Krause
Original Paper


Quorum sensing is used in many biological systems to increase decision accuracy. In quorum sensing, the probability that an individual adopts a behavior is a nonlinear function of the number of other individuals adopting this behavior. From an optimal decision-making perspective, individuals should adjust their quorum threshold to the particulars of the decision problem. Recent work predicts that a key factor here is the quality of social information. In particular, it is predicted that individuals should adjust their quorum thresholds such that it lies in between the average true and false positive rate of the other group members. We here test this prediction with a predator detection experiment. First, human groups observed a group of animals (projected on a white screen) in which a predator was present or absent, and each individual made an independent decision to escape or not. Second, individuals received social information on the decisions of their group members, after which individuals decided again. This social information, however, did not represent their own decisions but consisted of responses that either came from a high-performing group (i.e., many individuals detecting the predator) or from a low-performing group (i.e., few individuals detecting the predator). We found that individuals adaptively adjust their quorum threshold to the quality of the social information: when receiving social information from high-performing groups, individuals employed higher quorum thresholds than when receiving information from low-performing groups. Our study demonstrates that humans can quickly evaluate the quality of publicly available information and adaptively adjust their decision rules.


Decision-making Social information use Quorum thresholds Humans 



We thank Lysanne Snijders for help in running the experiments and Marc Naguib and Frank van Langevelde for hosting the experiments. We thank two anonymous reviewers for improving this manuscript. RHJMK is funded by an NWO Rubicon grant (825.11.014).

Supplementary material

265_2013_1659_MOESM1_ESM.pdf (221 kb)
ESM 1 (PDF 221 kb)


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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Ralf H. J. M. Kurvers
    • 1
    Email author
  • Max Wolf
    • 1
  • Jens Krause
    • 1
  1. 1.Department of Biology and Ecology of FishesLeibniz-Institute of Freshwater Ecology and Inland FisheriesBerlinGermany

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