This is Bird Note. You've probably heard the expression light as a feather, and bird

feathers are amazingly light, but they're also strong, holding up to gale force

winds and letting birds perform steep banked turns and dives. So how can bird

feathers be both strong and light? The answer begins with the feathers basic

building block, a molecule called beta keratin. It's a tougher version of the

keratin that makes up human fingernails and hair. With this sturdy material, bird

feathers can do more with less. But it's also about how those building blocks

are arranged. A bird feather has a central shaft with many thin barbs that

branch off, but zoom into those barbs and you'll see that there's a lot of

tiny barbules that branch off of the barbs. These barbules have hooks that

help lock the barbs together like Velcro. This branching structure provides

support throughout the feather, but it also has thousands of tiny gaps, making

feathers flexible and free of unnecessary weight. From tiny hummingbirds to big

strong ospreys, the intricate features of feathers allow for amazing displays

of speed and agility. For bird note, I'm Ariana Rimmel.