This is a rattle from a rattlesnake. I've always wondered what's inside a rattlesnake rattle, and how does it make sound? I thought they were like maracas. If you take a maraca and look inside, there are a bunch of small bits that knock around to make sound. But I was wrong. Small snake rattles don't make sound like maracas. Because let's take a look inside of this rattle. It's completely hollow. So it can't make sound like a maraca because there's nothing inside. Instead, watch closely. If I pull on the rattle, a piece comes off. Seems like the rattle can come apart. In different sections, this one is made up of 16 different sections. Every time the rattle snake sheds its skin, a bit of skin is left at the end of its tail. One of these. This bit of skin is added to the bottom of the rattle. That's how the rattle grows. But how do these rattles make noise? Look closely at this segment. It's cut in half. Notice the previous segment fits neatly inside of it. Here's an image that shows a cross section of the entire rattle. One section is highlighted in white. Can you tell how the sections fit loosely inside each other? It's not snug. It's a very loose fit. This allows all the segments to wiggle around and move. Now imagine if the rattle is shaken. Those segments can knock into each other over and over. Which makes a rattling sound. But not like this. This is not what a rattlesnake rattle really sounds like. As rattlesnakes can shake their rattle much faster than I can. While this sounds like a rattling sound. Rattle snakes can shake their rattle so fast it sounds more like a buzzing sound. And that's how rattlesnake rattles make sound.