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.