This is bird note.

Even if you had feathers, lightweight bones, and powerful wings, you would still lack something essential to flying like a bird.

The highly efficient breathing anatomy that powers the exertion of flight.

The human apparatus of diaphragm and lungs is just not up to the job.

It can't extract enough oxygen to fuel flight.

A bird's breathing anatomy is far more efficient than ours.

It is driven by large, thin-walled air sacs located throughout the body cavity.

The air sacs operate like bellows, first storing and then directing air

to create a one-way flow through the bird's lungs.

This parabronchial system for extracting oxygen from the air has a far greater surface

area than the lungs of a mammal, making sustained flight possible. And birds lack a diaphragm.

Instead, they inhale and exhale using special muscles that expand or contract the entire body cavity and air sacks.

The way they breathe allows migrating birds to fly in the thin air thousands of feet above the earth.

A feat we can only marvel at from below.

For bird note. For Bird Note, I'm Michael Stein.

Support comes from Wild Delight Bird Food,

offering a variety of blends designed to mimic the natural resources wild birds crave.

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