From the brains behind brains on, this is the Moment of Um.

Moment of Um comes to you from APM Studios. I'm Ruby Guthrie.

Um.

I must admit, I've been a little bit stressed out lately.

So I've been taking some time each day to do some deep breathing.

Each time, I like to take an imaginary journey to somewhere new.

Yesterday, it was a little brain vacation under the sea.

I imagined that I felt weightless in the warm ocean water,

with a bubble of air around me, keeping me totally safe.

As I drifted through a forest of gently waving seaweed,

I saw hundreds of colorful little fishes swimming every which way. I settled down onto the sandy seabed, closed my eyes, and took some more

deep breaths. When I opened my eyes, I realized I was surrounded by dozens of little cute crabs. And I thought,

hey, why don't we all do some deep breathing exercises together? But then I wondered,

do crabs even have lungs like I do? How do they breathe? Listener Dot was curious about this,

too.

So crabs are really special because they, for the most part, can breathe underwater,

and then they also can leave the water and do both. My name is Sarah McAnulty. I am a science communicator and a squid biologist for a nonprofit called Skype a scientist.

Regardless of where they are, they're still using their gills.

So fish have gills, crabs have gills, squid have gills. Lots of underwater animals have gills.

Gills are the organ in their body that encounters water and then pulls oxygen out of that

water. And so under the ocean, they're creating water flow across those gills so that they,

just like we breathe, we breathe in and out. They're doing the exact same thing, but instead of air across

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