A feather.

One of the most familiar and iconic symbols of nature.

Like a leaf, a flower, or a butterfly, the image of a feather is imprinted in our minds

from a young age.

By the time we reach adulthood, however, we might just take feathers for granted.

We think we've got them figured out.

We know what they look like and what they're for.

Therefore, the insulation in my puffy winter coat, of course.

And they're for fletching arrows and making fishing lures.

They're for adorning fancy ladies' hats and for religious ceremonies.

And, of course, they're for making quill pens.

The English word pen itself comes from the old French word for feather.

No, no, no. Those are the human uses for feathers, some mostly historic, and they are the least

important in the grand scheme of things from the perspective of nature across the eons.

Feathers are for birds. Feathers are indispensable to birds,

serving many critically important functions. How birds use their feathers is a big part of what

we're talking about today. But first we're going to inspect the structure of feathers, how they're put

together. They are such amazing, beautiful, and complex objects.

Imagine that one hair on your arm was replaced by a feather. How weird would that be?

This large, intricate, plasticy thing growing out of your skin, all colorful and dramatic.

It would be hard to ignore or take for granted. You'd probably poke at it and

examine its features carefully. Now imagine you're covered in feathers from head to heel. You'd have a

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