Fascinating Video Uncovers What's Inside A Rattlesnake's Rattle

How does the venomous snake make that distinctive sound?

If you live in an area populated by rattlesnakes, you’d probably recognize the warning sound of the reptile’s signature rattle. But what's inside the tip of a rattler’s tail?

YouTube channel “What’s Inside” has the answer.

The video, which has been viewed more than 21 million times to date, shows host Daniel Markham and his son, Lincoln, cutting open a rattlesnake’s rattle.

Watch the clip above to see what they discover (scroll to around 3:20 if you're impatient for the reveal). Then click here to learn more about rattlesnakes and their rattles.

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