Cuttlefish... octopuses... and squid have an almost otherworldly ability
to control their appearance.
What makes it possible are these spots.
They’re called chromatophores. They’re like tiny water balloons, filled with colored
pigment.
When the balloons expand, you see more pigment, more color...
When they contract, the color shrinks to a tiny dot.
The overall effect can be really dramatic.
And for good reason.
These animals don’t have protective external shells. They’re unarmored. Naked.
And they aren’t great swimmers, either.
Camouflage is their best defense. They have to be good at it.
Octopuses can change their body position and the pattern on their skin
to match rock or coral.
Octopuses and cuttlefish can even change the texture of their skin to throw off predators.
Become bumpier and more rock-like.
But squid often live in the open ocean. How do you blend in when there's nothing --
except water -- to blend into?
They do it by changing the way light bounces off their their skin -- actually adjust how
iridescent their skin is using light reflecting cells called iridophores.
They can mimic the way sunlight filters down from the surface. Hide in plain sight.
So how do they control all this color change?
Is it voluntary or some kind of built in reflex?
That’s what researchers at Stanford University wanted to know.
So…they anesthetized the squid and then snipped the nerve from the the brain that
controls the chromatophores, but only on one side of the animal.
The brain essentially couldn’t send messages to the tiny muscles that control those chromatophores
anymore.
… almost like turning off a light switch.
But after a few days, then they noticed something strange.
The chromatophores began blinking again… even though they were no longer getting signals
from the brain.
So what does this mean?
Well, what it suggests is that color change might be a bit like breathing is for humans.
Something we can either choose to do... or do automatically.
Only... even cooler -- because unlike breathing, color change requires an awareness
of your surroundings.
And in these animals, that awareness is spread throughout the skin…
as if the skin itself could see.
It would be as if your skin knew what color the walls were, even with your eyes closed.
For a soft and squishy creature trying to stay alive in a very big ocean --
it’s a pretty spectacular defense.