Wow, turns out that penguins use a “coat of air bubbles” as lubricant for when rocketing toward the surface at 19 km an hour (that’s 100 meters in about 19 seconds), enabling small species like Adelia penguins to leap 2-3 meters out of the water, and the big Emperor penguins to reach heights of 20-45 cm … enough to leap out of holes in the ice. And that the air doesn’t come from the lungs, but from beneath the feathers.
Penguins have great control over their plumage, Professor Davenport tells me.
They raise their feathers to fill their plumage with air, then dive underwater. As the birds descend, the water pressure increases, decreasing the volume of the trapped air. At a depth of 15-20 metres, for example, the air volume has shrunk by up to 75%.
The birds now depress their feathers, locking them around the new, reduced air volume.
The penguin then swims vertically up as fast as it can, and the air in the plumage expands and pours through the feathers.
“Because the feathers are very complex, the pores through which the air emerges are very small so the bubbles are initially tiny. They coat the outer feather surface.”
Crucially, this coat of small air bubbles acts as a lubricant, drastically reducing drag, enabling the penguins to reach lift-off speeds.´
Still, doesn’t help much when on land