Abstract
Running, swimming, or flying through the world, animals are constantly making decisions while on the move—decisions that allow them to choose where to eat, where to hide, and with whom to associate. Despite this most studies have considered only on the outcome of, and time taken to make, decisions. Motion is, however, crucial in terms of how space is represented by organisms during spatial decision-making. Using a combination of modeling, automated tracking, computational reconstruction of sensory information, and immersive ‘holographic’ virtual reality (VR) experiments with fruit flies, locusts, and zebrafish, I will demonstrate that this time-varying representation results in the emergence of new and fundamental geometric principles that considerably impact decision-making. Specifically, we find that the brain spontaneously reduces multi-choice decisions into a series of abrupt (‘critical’) binary decisions in space-time, a process that repeats until only one option—the one ultimately selected by the individual—remains. Due to the critical nature of these transitions (and the corresponding increase in ‘susceptibility’) even noisy brains are extremely sensitive to very small differences between remaining options (e.g., a very small difference in neuronal activity being in “favor” of one option) near these locations in space-time. This mechanism facilitates highly effective decision-making, and is shown to be robust both to the number of options available, and to context, such as whether options are static (e.g. refuges) or mobile (e.g. other animals). In addition, we find evidence that the same geometric principles of decision-making occur across scales of biological organisation, from neural dynamics to animal collectives, suggesting they are fundamental features of spatiotemporal computation.
Biography
Iain Couzin is Director of the Max Planck Institute of Animal Behaviour and a Professor and Director (Speaker) of the German Research Foundation (DFG) Excellence Cluster “Centre for the Advanced Study of Collective Behaviour” at the University of Konstanz, Germany. Previously he was a full Professor in the Department of Ecology and Evolutionary Biology at Princeton University. His work aims to reveal the fundamental principles that underlie evolved collective behaviour, and consequently his research includes the study of a wide range of biological systems, from neural collectives to insect swarms, fish schools and primate groups. In recognition of his research, he has been the recipient of the Searle Scholar Award (2008); one of the top five most cited papers of the decade in animal behaviour research (1999–2010); the National Geographic Emerging Explorer Award (2012); the Scientific Medal of the Zoological Society of London (2013); named a Web of Science Global Highly Cited Researcher (2018–2022 and 2024); the Lagrange Prize (for fundamental contributions to complexity science, 2019); the Falling Walls Life Sciences Award and the Gottfried Wilhelm Leibniz Prize (Germany’s highest research honour, 2022); the Rothschild Distinguished Fellowship at the University of Cambridge (2023); the Fyssen International Prize (2024); and the President’s Medal of the Royal Society of Entomology (2025).