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Hey, Squeaks! How’s it going? [Squeaks squeaks].

Is it just me, or is it a little stuffy in here today? [Jessi yawns]. Wow! I've been yawning a lot lately, and I wanted to figure out why!

Scientists actually aren’t totally sure why we yawn, but a lot of them think that we yawn to cool down our brains because sometimes they can get too warm! Whoa! It’s a very weird idea, but it also makes a lot of sense if you think about when people tend to yawn.

You yawn a lot when you’re tired right? And scientists have found that our brains are a little warmer than usual when we’re tired, and right before we fall asleep, so that’s when that sleepy-time yawn comes in. Your brain can also get warm if you’re generally just warm.

So that’s why you might yawn more if it’s a summer day or if you’re in a hot and stuffy room. Hey, Squeaks, that might be why I yawned! [Squeaks squeaks]. On the other hand, you might also yawn when you need to focus on something, because you think more clearly with a cooler brain.

Maybe you’re settling down to read a book and a yawn just comes out. It doesn’t mean you’re bored of the book; it just might be your body’s way of getting your brain ready to read. So I might have also yawned because I wanted to focus on what we’re talking about!

But how does yawning cool our brains down? Well, let’s look at a yawn a little more closely. The first thing that happens when you yawn is that you open your mouth really wide and you take a big, deep breath in.

As you’re breathing in, the air actually cools down the blood that’s going to your brain. There’s another time people yawn a lot that we haven’t talked about yet! What about when one person yawns -- [Jessi yawns] [Squeaks yawns] -- and someone else yawns right after.

Can you really catch a yawn from someone else? Well, the answer is … sort of! People do usually yawn when they see someone else doing it, although it depends how old you are.

If you’re younger than five years old, you might not experience contagious yawning at all, though you’ll still definitely yawn! So, why are yawns contagious? Well, it could be that if we see someone yawning, even though we’re not really aware of it, our brain goes, “Oh, that’s a good idea -- maybe I should do it, too!” So yawning could be a way we communicate with each other!

It might also be the same thing as when you smile when someone else smiles – it’s a way of sharing a feeling. We’re naturally social creatures, and sometimes we just want to feel what another person is feeling so that we can understand them a little bit better. It’s like when you might get sad when you’re watching a sad movie, even though you know it’s just a movie.

There’s still a lot we don’t know about yawning, though. For example, some people “catch” them way more easily than other people and we’re not really sure why! [Jessi yawns]. That is a lot of yawns, Squeaks!

How about we get a little bit of fresh air! [Squeaks squeaks]. Thanks for joining us! If you have more questions about yawning, or the way our bodies work, or anything at all, just grab a grown-up and leave a comment below, or send us an email at kids@scishow.com.

We’ll see you next time, here at the Fort! ♪.