Collective motion from local attraction and non-standard modeling assumptions

Mathematical Biology

04 October 14:00 - 14:45

Daniel Strömbom - Swansea University

How animals coordinate themselves in moving groups, such as flocks of birds and schools of fish, is not fully understood. The standard explanation is that the individuals in moving animal groups interact with nearby neighbors via attraction, repulsion and alignment (taking the average heading of nearby individuals). However, over the past decade this view has been challenged, in particular the idea that alignment is the main driver of the coordinated motion, both by experimental studies and modeling work. In particular, a number of alignment-free attraction and repulsion models have been proposed that can produce the same group types that alignment based models can, i.e. polarized groups, mills and swarms, and some experimental studies fail to find signs of the alignment interaction. Adding to this, we recently found that when a number of non-standard (but arguably more realistic) modeling assumptions relating to how individuals update their positions are used attraction alone can also produce polarized groups, mills and swarms. Suggesting that perhaps attraction, the same social force that makes the individuals aggregate in the first place, may also be the key driver of their collective motion. In this talk I will present, and provide context for, our findings and explain why they may be useful to consider when interpreting experimental data.
Mats Gyllenberg
University of Helsinki
Torbjörn Lundh
Chalmers/University of Gothenburg
Philip Maini
University of Oxford
Roeland Merks
Universiteit Leiden
Mathisca de Gunst
Vrije Universiteit Amsterdam


Roeland Merks


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