With the help of Poul Larsen, a mechanical engineer at the Technical University of Denmark, they analyzed hours of underwater footage and discovered that the penguins were doing something that engineers had long tried to do with boats and torpedoes: They were using air as a lubricant to cut drag and increase speed.For me, the real significance of this is the sheer astonishment of it. Air lubrication is cutting edge engineering in the twenty-first century -- indeed, we would not have thought to look for it in nature if engineers were not working out how to use it on our own machines -- but penguins were there long ago. To know this reductive scientific fact about penguins does not make them less wonderful, but more so.
When an emperor penguin swims through the water, it is slowed by the friction between its body and the water, keeping its maximum speed somewhere between four and nine feet a second. But in short bursts the penguin can double or even triple its speed by releasing air from its feathers in the form of tiny bubbles. These reduce the density and viscosity of the water around the penguin’s body, cutting drag and enabling the bird to reach speeds that would otherwise be impossible.
Monday, February 25, 2013
Penguin Bubbles, or, Science Uncovers Another Miracle of Nature
find out for themselves: