Deep Look | This Adorable Sea Slug is a Sneaky Little Thief | Season 5 | Episode 15

This nudibranch is a little thief.

It’s got no problem with helping itself to its neighbor’s stuff.

Also called sea slugs, they’re basically snails but without the protective shells.

They’re soft and squishy… and not exactly speedy.

You’d think they’d want to keep a low profile.

But they’re out there - showing off.

Because their colors are actually a warning.

Some of these nudibranchs have found a devious way to defend themselves, by stealing weapons from someone else.

See this?

It’s a hydroid.

Friendly little seaweed, maybe?

Nope, it’s actually an animal related to jellyfish.

And it has the sting to prove it.

Hydroids have tentacles they use to catch food floating by.

They’re covered in stingers that pack an excruciating, paralyzing venom.

they’re called nematocysts.

That’s them right there.

They’re the same type of potent weaponry that make jellyfish so dangerous.

Mess with them and they explode, shooting out tiny harpoons full of venom.

Which is why most creatures want nothing to do with them.

But nudibranchs are all about it.

They devour hydroids.

Lots of those nematocysts fire off in the nudibranch’s mouth.

But it’s unfazed.

They seem to have a taste for spicy food.

Here’s the thing though, some of those nematocysts don’t detonate right away.

They aren’t mature enough yet.

And that’s the key to the nudibranch’s scheme.

It swallows the immature stingers whole.

And they travel through the nudibrach’s crazy-looking digestive tract which extends into the spikes on its back, called cerata.

See that that dark area inside?

It’s part of the digestive system that connects to the gut.

The stingers are collected at the very tip, where they mature.

Until the nudibranch feels threatened.

That’s when this colorful little kleptomaniac pulls out the big guns.

It points its bristling cerata at its attacker, squirts out the stolen nematocysts and they explode, launching their venomous harpoons.

That’s enough to repel just about anyone looking for a quick bite.

Just goes to show - if you’re not born with certain assets, it doesn’t hurt to borrow them.

Hey, It’s Lauren.

I’m back - and I missed you!

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