Physics

Why penguins do the wave

Journal name:
Nature
Volume:
505,
Page:
265
Date published:
DOI:
doi:10.1038/505265e
Published online

Highly read on iopscience.iop.org 9 Dec–8 Jan

FRANS LANTING/CORBIS

Physicists have explained how waves of coordinated motion sweep through huddles of male emperor penguins (Aptenodytes forsteri; pictured) as they try to keep warm while incubating eggs in the Antarctic.

Daniel Zitterbart and Richard Gerum at the University of Erlangen-Nuremberg, Germany, and their colleagues analysed video recordings of penguin huddles and built a mathematical model to study the waves. The authors found that any penguin taking a step of two centimetres or more within a densely packed huddle can trigger ripples of disturbance as nearby penguins readjust to keep close (but not too close) to each other.

The movements were similar to those seen in traffic jams in which waves begin at the front of the queue and travel backwards. However, in penguin huddles, waves can move in multiple directions from any location.

New J. Phys. 15, 125022 (2013)

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