An octopus “sees” with its skin

exploring-a-jar

A two-spot octopus explores a jar.
Photo by Nathan Rupert/CC, Flickr

An octopus “sees” with its skin
Adapted from cbc.ca by Nancy Carson
Level 2

Cover the eyes of an octopus
with your hands.
Or put a blindfold over its eyes.
It will not be blind!

New Study
Researchers studied pieces of skin
from a California two-spot octopus.
Octopus skin is different from its eyes.
The skin cannot see details.
But the skin notices changes in light.

Hiding in plain sight
Octopuses can change their colour
to look like rocks or sand.
They can change to gray, brown,
pink, blue or green.
This is called camouflage.
Enemies like sharks, eels
and dolphins swim by.
They do not notice the octopus.

A two-spot octopus can look like rocks. Photo by BiteYourBum.Com Photography

A two-spot octopus can look like rocks.
Photo by BiteYourBum.Com Photography

No brain needed
Researchers did not test living octopuses.
They tested pieces of octopus skin.
They turned lights onto the skin.
Spots on the skin got bigger.
This made the skin look darker.
This reaction happened without
the help of the animal’s eyes.
And without the help of its brain.

A cloud of black
When an enemy discovers an octopus,
the octopus shoots a cloud of black ink
into the water.
Then the enemy cannot see the octopus.
The ink also has something in it.
This substance makes it difficult
for the enemy to smell the octopus.

Escape
The octopus can flee quickly.
Its soft body can also squeeze into
very small cracks.
Its enemies cannot follow.
If it loses an arm,
it can grow another arm.
Octopuses have a sharp beak.
So, they can give a nasty bite.
Seals, whales and large fish
will hunt octopuses.

Annoyed two-spot octopus Photo by Thomas White/CC, Flickr

Annoyed two-spot octopus
Photo by Thomas White/CC, Flickr

Habitat
Most octopuses stay
along the ocean floor.
Other kinds of octopus live
near the water’s surface.
Crabs, shrimp and lobsters
are some of their favourite foods.

Living alone
Octopuses live alone in a protected area or den.
They can grow to 1.5 metres in length.
And they can weigh up to 10 kilograms.
Scientists say octopuses are
the most intelligent of all animals
which have no backbones.

Vocabulary:

  1. blindfold: a piece of cloth tied around the head
    to cover someone’s eyes
  2. camouflage: a shape or colouring used to hide a person or thing
    so that they look like their background

Links:

  1. Octopus “super mom” – front page story and audio
  2. Octopus escape or octopus exploring its new tank?
  3. Facts about octopuses
  4. Animals playing Hide and Seek:
    Can you spot the animal in each picture?
  5. Ringo Starr of The Beatles wrote Octopus’s Garden in 1969
    after he left the group
    :