Name: This Adorable Sea Slug is a Sneaky Little Thief | Deep Look
Uploaded: 2025-05-04T17:11:35.000Z
Duration: 4 min 11 s
Description: Thousands of YouTube videos with English-Chinese subtitles! Now you can learn to understand native speakers, expand your vocabulary, and improve your pronunciation...

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.

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

Because their colors are actually a warning.

Some of these nudibranchs have found a devious way to defend themselves.

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

Hydroids have tentacles they use to catch food floating by, they're covered in stingers that pack an excruciating, paralyzing venom.

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

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 scheme.

It swallows the immature stingers whole, and they travel through the nudibranch's crazy looking digestive tract, which extends into the spikes on its back, called cerata.

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

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

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.

This 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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