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Where Physics Meets Behavior in Animal Groups

Chantal Nguyen1 and Orit Peleg1,2,3

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PRX Life 3, 037001 – Published 24 July, 2025

DOI: https://doi.org/10.1103/tjz9-btmj

Abstract

This review explores the critical role of the physics of the body and the environment in shaping behaviors within the emerging field of the physics of social interactions. We revisit the intriguing case study where a dead fish, lacking neural control, appeared to swim upstream, propelled by its body resonating with vortices. This example expanded the conventional view of behavior as solely a product of biological processes, underscoring the significant influence of physical forces on living and nonliving entities alike. We build upon this foundational understanding and review how the physical characteristics of individual organisms interact with other individuals and with their environments to produce complex group dynamics, focusing on key examples: hydrodynamic interactions in fish schools where individual movements are influenced by water flow and collective swimming patterns; thermoregulation in penguin huddles, where individuals closely pack to minimize heat loss and optimize energy use in harsh climates; and raft formation in ants as a survival strategy during floods, leveraging their collective buoyancy and waterproofing properties. Our discussion emphasizes the importance of considering both the physics of the bodies and the environmental factors in understanding these intricate dynamics. By combining findings from a range of taxa to showcase the interplay between physical and biological aspects of collective social behaviors, we hope to encourage further research that explores their many facets and implications.

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PRX Life 3, 037001– Published 24 July, 2025
  • Received 24 March 2024
  • Accepted 2 July 2025
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