Public Evening Lecture by Professor Jens Krause, PhD (Leibniz Institute for Aquatic Ecology and Inland Fisheries at the Berlin Research Alliance e.V.)
Studies on collective cognition provide numerous examples of how the efficient dissemination of information within groups leads to benefits as group size increases. However, little is known about whether groups also amplify maladaptive information, such as false alarms, and whether such costs reduce potential benefits. In this study, we examined wild fish schools that collectively respond with escape dives when attacked by birds. We analyzed the collective response to bird attacks as well as to similar but harmless flyovers as a function of school size. Larger schools became increasingly better at detecting predator attacks, while their response to harmless flyovers remained constant. Furthermore, decision time decreased as school size increased. Larger schools were thus able to simultaneously overcome two central trade-offs typical of individual decision-making: the trade-off between false and true alarms, and the trade-off between speed and accuracy.
I will place these results in the context of examples of human collective cognition dealing with similar problems and attempt to derive a general definition of collective cognition from them. At the end of my talk, I will explain how our work on collective cognition is part of a broader research program on the “Science of Intelligence” being developed in our Cluster of Excellence of the same name in Berlin (https://www.scienceofintelligence.de/).
Moderators: Denise Becker and Jule Meyer, B.Sc.
