Penguin Groups Move Like Jammed Traffic

This is Scientific American's 60-Second Science. I'm Allie Wilkinson. Got a minute?
In the harsh winters of Antarctica, emperor penguins form tight huddles to protect themselves from freezing temperatures and roaring winds.
These huddles allow the penguins to conserve heat and energy.
But they make moving a complex group effort.
Researchers watching video of penguin huddles saw movement in wave-like patterns.
To study the wave propagation, they employed a mathematical model that applies to flocks of birds, schools of fish and even traffic jams.
It turns out that the way tightly grouped penguins move is a lot like cars in stop-and-go traffic.
Each penguin needs to go only about an inch in any direction for its neighbors to react.
This action helps the penguins maintain an optimal distance from each other,
so that they can keep the huddle as dense and therefore warm as possible.
The study appears in the New Journal of Physics.
With the exception of individuals on the perimeter, penguins in a huddle are completely surrounded.
But instead of the penguin equivalent of road rage, perhaps they settle their tiny turf differences with an icy stare.
Thanks for the minute, for Scientific American's 60-Second Science. I'm Allie Wilkinson.