WEBVTT

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What could octopuses possibly
have in common with us?

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After all, they don't have lungs, spines,
or even a plural noun we can all agree on.

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But what they do have is the ability
to solve puzzles,

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learn through observation,

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and even use tools,

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just like some other animals we know.

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And what makes octopus intelligence
so amazing

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is that it comes 
from a biological structure

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completely different from ours.

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The 200 or so species of octopuses

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are mollusks 
belonging to the order cephalopoda,

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Greek for head-feet.

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Those heads contain impressively
large brains,

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with a brain to body ratio similar
to that of other intelligent animals,

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and a complex nervous system with
about as many neurons as that of a dog.

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But instead of being 
centralized in the brain,

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these 500 million neurons are spread out
in a network of interconnected ganglia

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organized into three basic structures.

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The central brain only contains
about 10% of the neurons,

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while the two huge optic lobes
contain about 30%.

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The other 60% are in the tentacles,

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which for humans would be like
our arms having minds of their own.

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This is where things 
get even more interesting.

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Vertebrates like us have a rigid skeleton
to support our bodies,

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with joints that allow us to move.

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But not all types of movement are allowed.

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You can't bend your knee backwards,

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or bend your forearm in the middle,
for example.

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Cephalopods, on the other hand,
have no bones at all,

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allowing them to bend their limbs
at any point and in any direction.

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So shaping their tentacles

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into any one of the virtually 
limitless number of possible arrangements

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is unlike anything we are used to.

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Consider a simple task,
like grabbing and eating an apple.

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The human brain contains a neurological
map of our body.

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When you see the apple,

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your brain's motor center activates
the appropriate muscles,

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allowing you to reach out with your arm,

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grab it with your hand,

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bend your elbow joint,

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and bring it to your mouth.

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For an octopus, 
the process is quite different.

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Rather than a body map,

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the cephalopod brain 
has a behavior library.

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So when an octopus sees food,

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its brain doesn't activate 
a specific body part,

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but rather a behavioral response to grab.

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As the signal travels through the network,

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the arm neurons pick up the message

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and jump into action 
to command the movement.

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As soon as the arm touches the food,

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a muscle activation wave travels
all the way through the arm to its base,

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while the arm sends back another wave
from the base to the tip.

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The signals meet halfway
between the food and the base of the arm,

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letting it know to bend at that spot.

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What all this means is that each
of an octopus's eight arms

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can essentially think for itself.

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This gives it amazing flexibility 
and creativity

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when facing a new situation or problem,

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whether its opening 
a bottle to reach food,

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escaping through a maze,

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moving around in a new environment,

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changing the texture and the color
of its skin to blend into the scenery,

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or even mimicking other creatures
to scare away enemies.

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Cephalopods may have evolved 
complex brains

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long before our vertebrate relatives.

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And octopus intelligence isn't just useful
for octopuses.

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Their radically different nervous system
and autonomously thinking appendages

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have inspired new research

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in developing flexible robots
made of soft materials.

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And studying how intelligence can arise
along such a divergent evolutionary path

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can help us understand more about
intelligence and consciousness in general.

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Who knows what other forms 
of intelligent life are possible,

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or how they process the world around them.