- Whoa!

- Hello?

Tree?

I'm Annie.

Who are you?

Are you spooky?

♪ ♪ [fireflies buzzing] - [gasps] [both laugh] - Kids, this isn't a spooky tree.

It's a home for some fireflies.

- Wait, those lights are fireflies?

- Right, fireflies' bodies light up at night, which makes this tree look like it's glowing.

both: Ooh, pretty!

- My hypothesis was right.

The tree wasn't alive.

The fireflies were, inside the tree.

- Yes, Buddy, very good.

Fireflies have a chemical reaction in their bodies called "bioluminescence" in order to communicate with each other.

It says, "Here I am," to other fireflies.

- And the glowing bioluminescence also tells other animals, "Hey, don't eat me.

I don't taste very good."

- Oh, that's useful to know.

- Are fireflies the only creatures that glow?

- Nope.

Look around.

Once you know what you're looking for, you can find them more easily.

- Look, a little glowing trail.

- That leads us right to the glow worm.

See?

- Why does it leave a glowing trail?

- So it can distract animals who try to eat it and then escape.

- Wow.

So glowing is really useful.

- And not spooky at all.

- If you look around, you can see glowing in lots of places.

- Whoa.

Neat-o!

- I'm glad we went out at night.

I like this adventure.

- Mr. and Mrs. Pteranodon, is it all right if we stay here with the fireflies a little longer?

- I guess spending time with the fireflies is sort of special.

- A sleepover treat.

- Yay!

Let's have a glow-in-the-dark dance party!

[all humming] all: Rawr!

[all humming] Rawr!

[all humming] Rawr!

[all humming] Rawr!