
Watch These Cunning Snails Stab and Swallow Fish Whole
Season 5 Episode 10 | 4m 8sVideo has Closed Captions
Cone Snails have an arsenal of tools and weapons under their pretty shells.
Cone Snails have an arsenal of tools and weapons under their pretty shells. These reef-dwelling hunters nab their prey in microseconds, then slowly eat them alive.
Problems with Closed Captions? Closed Captioning Feedback
Problems with Closed Captions? Closed Captioning Feedback

Watch These Cunning Snails Stab and Swallow Fish Whole
Season 5 Episode 10 | 4m 8sVideo has Closed Captions
Cone Snails have an arsenal of tools and weapons under their pretty shells. These reef-dwelling hunters nab their prey in microseconds, then slowly eat them alive.
Problems with Closed Captions? Closed Captioning Feedback
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Learn Moreabout PBS online sponsorshipCone snails are striking ... in more ways than one.
They lurk in the sand around coral reefs.
And wait til you see what's under the hood.
That pretty veneer is hiding an impressive array of tools ... and weapons.
A cone snail's breathing tube, called a siphon, is actually more like a sheet of muscle rolled into a snorkel.
Besides drawing water to gills deep in its shell, the siphon also can pick up the scent of unsuspecting prey.
That's when the cone snail goes spearfishing.
Its extendible proboscis is packing a concealed weapon.
A tiny, hollow harpoon made of chitin, the same tough stuff in a lobster shell.
And the end of the proboscis is tricked out with receptors.
Taste buds.
That help it close in on its target.
When it strikes, the snail's pace jumps to light speed.
The embedded harpoon doubles as a hypodermic needle to inject the victim with paralyzing venom.
As it reels in the catch, the cone snail uses another covert tool called a rostrum.
It opens up to swallow the fish whole.
Some cone snails hunt more familiar prey.
Other snails.
The smaller snail digs down to hide its shell opening.
The predator looks for a way in.
When it finds it, the hunter hits its prey with more than one shot of venom.
A lot is going on in the fifth of a second before the snail fires that harpoon.
So let's rewind and break it down.
First the proboscis flexes as the muscles inside prepare for the strike.
Then the venom floods into the proboscis, but stops just short of the harpoon.
A round muscle holds the lethal fluid in check, like a kink in a hose, building even more pressure.
Then, everything blows, and propels the venom into the harpoon, the harpoon into the prey.
What has scientists interested in cone snails is that their venom varies not only from species to species but also from individual to individual, and even from shot to shot.
In fact they seem to mix their venom cocktail on the fly from thousands of unique ingredients, each with its own purpose.
All this variety means a world of new drugs could lie under that shell.
Novel ways to treat things like chronic pain, Alzheimer's, and diabetes.
Most cone snail strikes hurt as much as a bee sting.
A few can kill you though, like this geography cone, it has the most venomous sting in the world.
Here's a tip: Don't go gathering these shells when you're snorkeling in Australia.
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