If you are an animal looking for a resource, such as food or a mating partner, in a huge area, where the resource is randomly distributed; what tactic would you use to find it? Biologists have found that many animals follow so-called Lévy walk patterns to optimize their foraging. A Lévy walk, also known as Lévy flight, is a random walk in which an animal makes many short movements, with an occasional long movement. The lengths of these movement are distributed according to rules discovered by the French mathematician Paul Lévy.
And it’s not just animals that use this tactic to find food. Our own human ancestors also used it for foraging. Even now, we as modern humans often display this type of movement. In the past few decades, scientists have shown that Lévy walk dynamics occur in human mobility across various spatial scales, for instance when we move through cities or on a University Campus.
A small team of researchers from the University of Amsterdam decided to study whether humans also display this type of movement at large dance events. Since almost everyone nowadays carries a mobile phone, this offered the researchers an opportunity to study human movement in a real-life field setting. They used anonymised data from nearly 600 WiFi access points within the Johan Cruijff ArenA, a large football stadium in Amsterdam, to track the movements of people during a dance event with the highly popular dj Armin van Buuren in the spring of 2017.
While it’s clear that the tens of thousands of visitors were not at the event only looking for food, drinks or even a mating partner, their movements, while not pure Lévy walks, do exhibit properties of this typical movement pattern commonly observed in animal foraging. PhD candidate Philip Rutten states: ‘Although we find no strict evidence of Lévy walks, we do see characteristics that have been found in many other animal movement studies and have been identified as optimal search strategies.’
Philip Rutten, Michael H. Lees, Sander Klous and Peter M.A. Sloot, Intermittent and persistent movement patterns of dance event visitors in large sporting venues, in: Physica A: Statistical Mechanics and its Applications, Volume 563, February 1 2021.Doi: https://doi.org/10.1016/j.physa.2020.125448