Thanks to the Monterey Bay Aquarium and  their research and technology partner.

MBARI for partnering with us  on this episode of SciShow. They hope that you LARVA this episode! [♪ INTRO].

This is a giant larvacean. Sorry, let  me zoom in. THIS is a giant larvacean.

The huge structure around it is it’s home —  a palace it built for itself… out of snot. It’s a magnificent feat of engineering, especially for a small,  tadpole-y looking creature. And these mansions make larvaceans  a key part of the ocean ecosystem.

But the weirdest thing is that,  as alien as they might seem, larvaceans are actually among our  closest living boneless relatives! And because of that, they can help us  understand ourselves a little better. Larvaceans are tiny compared  to their mucus mansions.

A snot palace can easily be  a meter wide in some species, while the architect inside is  less than 10 centimeters long! These structures have to be so big because  they act as filters to catch all the little bits of food that rain down from  above—what scientists call marine snow. But while “giant snot palace”  looks and sounds messy, there’s complex structure hidden within.

This was only recently uncovered by scientists,  as these balls of snot are too fragile to be brought up from the  depths without damaging them. Researchers at MBARI actually  designed a way to scan the houses in their natural environment using lasers  attached to a remotely operated vehicle. They then used the scans to generate  three dimensional visualizations — which one can enter and fly through  using a virtual reality headset!

This revealed that each palace is full  of intricate chambers and passageways! We don’t fully understand how this sophisticated  plumbing works, but the gist is that the critter inside flaps its tail to move  water through multiple layers of filters. The outer filter catches anything  that’s too big for the animal to eat, while the inner ones channel ideally-sized  food into the animal's mouth.

And those tubes and such mean that this  water movement happens without giving away the location of the actual animal to  anything prowling the ocean for a meal. Here’s what’s really mind  blowing about all this, though: each massive, intricate snot palace  may only last for a day or less. After that it becomes so clogged that  the animal abandons the entire thing!

But no worries, it can whip up  a new one in less than an hour. It just oozes snot out of  some cells on its head region and inflates the chambers like  balloons — and tada! Instant house!

Figuring out exactly how they pull  that off could help us improve our 3D printing skills, or speedily build  structures underwater or on other worlds. But regardless, the discarded  houses don’t go to waste. The food-filled snot ball sinks  as fast as 800 meters a day!

So these empty mansions soon  become tasty snacks for creatures that hang out in deeper waters and for  sea floor scavengers like sea cucumbers. They also make larvaceans big  players in the global carbon cycle. You see, every living thing in  the ocean is built from carbon that has entered the water as carbon dioxide.

When those creatures die, the carbon in  them has the chance to return to the air. But sinking larvacean snot  palaces trap this carbon, speeding it to the deep instead, where it  can be locked up for millions of years. In fact, in some places, they might  transfer more carbon to the ocean floor than any other kind of plankton!

And removing carbon from seawater means  more CO2 from the air can dissolve in— so they are doing their part to lower  the carbon dioxide of our atmosphere! That’s not the only way  they’re helping us out either. They’ve also recently emerged as model organisms.

That’s because, like us, they’re  part of a group called chordates! So they share a decent amount in common with us, especially when it comes to which  genes are active early on in life, when we also kind of look like tadpoles. They also grow fast and have clear bodies, all of which makes them useful for  studying how genes affect development.

So these deep sea architects  are inspiring engineers and developmental researchers alike! And there’s still a lot  more we can learn from them. Thanks again to MBARI and  the Monterey Bay Aquarium for collaborating with us  on this episode of SciShow.

You can follow MBARI's research and technology on their very amazing and  fun-to-watch YouTube channel. I love it. How do I — is it clear?

And you can help support the Monterey  Bay Aquarium’s ongoing animal care and operations by making a gift  at montereybayaquarium.org/donate. [♪ OUTRO].