How do shuffling waves help Emperor Penguins stay warm in a place where temperatures plunge to minus 58 degrees Fahrenheit and wind speeds reach 124 mph?

It’s not a riddle–but a question that researchers now have more information about.

A new study provides insight on Emperor Penguin behavior, revealing what causes hundreds to thousands of them to constantly shuffle in wave-like motions that ripple through the huddle.

Earlier research has shown that Emperor Penguins maintain tight, constantly-moving huddles with wave-like movements for warmth. Now researchers say they have a better idea of what governs and triggers the stop-and-go waves, thanks to the help of a mathematical model.

The findings were revealed in a new study titled “The Origin of Traveling Waves in Emperor Penguin Huddle” and was published in the December issue of the New Journal of Physics.

It was thought that  the waves were triggered by penguins disturbing the huddle structure and that the waves removed the defects and restored order– although the mechanisms for doing that were not known.

The new study presents a model that shows how, “wave patterns emerge from simple rules involving only the interactions between directly neighboring individuals, similar to the interaction rules found in other jammed systems, e.g. between cars in a traffic jam.”

They also found that the threshold distance between each penguin estimated to be around 2 centimeters apart– maximizing the density of the huddle without compromising the animal’s own insulation.

“We were really surprised that a traveling wave can be triggered by any penguin in a huddle, rather than penguins on the outside trying to push in,” said Daniel Zitterbart, co-author of the study from Alfred Wegener Institute, Hemholtz Center of Polar and Marine Research.

Emperor penguins are the tallest and heaviest members of the penguin family, with the average birds reaching 45 inches tall, weighing anywhere from 40 to 99 pounds and living an average lifespan of 15 to 20 years in the wild.

Emperor penguins mate on the open Antarctic ice, the female lays a single egg, which the male nurtures– withstanding the harsh arctic temperatures for more than 2 months until the egg hatches.