
If Your Hands Could Smell, You’d Be an Octopus
Season 4 Episode 4 | 3m 12sVideo has Closed Captions
Those hundreds of powerful suckers on octopus arms do more than just stick.
Those hundreds of powerful suckers on octopus arms do more than just stick. They actually smell and taste. This contributes to a massive amount of information for the octopus’s brain to process, so octopuses depend on their eight arms for help. (And no, it's not 'octopi.')
Problems with Closed Captions? Closed Captioning Feedback
Problems with Closed Captions? Closed Captioning Feedback

If Your Hands Could Smell, You’d Be an Octopus
Season 4 Episode 4 | 3m 12sVideo has Closed Captions
Those hundreds of powerful suckers on octopus arms do more than just stick. They actually smell and taste. This contributes to a massive amount of information for the octopus’s brain to process, so octopuses depend on their eight arms for help. (And no, it's not 'octopi.')
Problems with Closed Captions? Closed Captioning Feedback
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Learn Moreabout PBS online sponsorshipThis octopus is making a quick escape... with the help of its suckers.
The suckers are incredibly strong.
And while we only have two hands to grab things, an octopus holds on with hundreds of suckers running up and down each arm.
Suckers come in pretty handy to get around.
Or to grab a bite to eat.
Or to hang onto your keeper's arm.
So how do suckers stick so well?
It's not super glue.
It's water pressure.
Each sucker has a ring called an infundibulum.
It creates a water-tight seal.
Inside the sucker there's a chamber, like a cup, called the acetabulum.
It's full of water.
When the octopus expands the chamber, it lowers the pressure inside.
The higher pressure outside pushes against the sucker creating a powerful grip.
Suckers get such a workout that their skin sloughs off every few weeks.
See that ring-shaped piece of skin floating by?
It used to be the bottom of a sucker.
Suckers have another super-power.
They actually can smell and taste.
That helps the octopus tell there's no snail inside this shell.
Hundreds of suckers tasting and smelling, and flexible arms moving every which way, create a huge amount of information -- a lot for the octopus' central brain to process.
So each arm has a mind of its own.
In fact, two thirds of an octopus' neurons are in its arms.
That means the central brain isn't really calling all the shots.
The central brain tells the arms how fast to move.
But the instructions on how to reach come from each arm.
It's a nifty way to process all that information, making the octopus the well-choreographed creature we know.
AMY: Hi.
This is Amy Standen.
You may have noticed a different voice on Deep Look today.
My good friend and fellow science reporter Lauren Sommer is taking over for me as host of the series.
LAUREN: Thanks, Amy.
I'm excited to be here.
If you like cephalopods, check out our episode on squid skin.
And if you miss Amy's voice, listen to her podcast "The Leap," at the link below.
See you next time.
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