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Chris King

Eight-footed
An octopus is an animal with eight legs that lives in the sea. Actually its English name means 'eight footed'. It comes from Greek - oktapous. 
But an octopus' 'legs' or 'feet' are really arms, four on either side of its body. We call them 'tentacles'. 
There are about 300 kinds of octopus, ranging from very small ones to 'giant' kinds.
Unique biology
Octopuses are unlike creatures that live on the land. Apart from  having eight tentacles, many of them have no bones - or skeleton - at all. Unlike many other ocean-living creatures they don't have shells either. Their bodies are usually completely soft. The only hard part of their body is their beak. An octopus' beak is very similar to a parrot's beak. 
Another very strange thing about octopuses is they have three hearts. But these don't help them to live longer. Male octopuses usually die around two months after they mate. Female octopuses usually die very soon after their eggs have hatched. 
It takes around one month for octopus eggs to hatch. The mother octopus spends so much time looking after her eggs, she forgets to eat.
Avoiding predators
Octopuses can be very strong. The biggest kinds can have tentacles that are 4 metres long. Some  weigh more than 70kg. 
The North Pacific Giant Octopus is usually around 15kg. But some people claim they have seen ones that weigh around 270kg, with 9-metre-long tentacles. These giant creatures are not afraid of many other sea animals. They have even been known to kill certain kinds of sharks. But most octopuses are quite small. Usually, when they are attacked, they try to hide. One way they escape is by squirting black ink into the water. This makes it hard for other animals to see them. The ink is melanin. It is the same substance that gives our skin colour. 
Another interesting thing they might do, if they are attacked, is to wrap their tentacles around their bigger, stronger attacker.
Invertebrates
Octopuses are invertebrates. Invertebrates are animals with no backbones, or vertebra. 
Octopuses are probably the most intelligent of all the invertebrates. Scientists have done experiments with octopuses and found they can solve problems and remember how to find their way out of mazes. This means they have short- and long-term memories. 
Unfortunately, they only live for around two years so they can't learn a lot.
A world of sensation
We know octopuses are highly  intelligent - probably about as intelligent as cats. We also know they   have very good eyesight. They have   two eyes on either side of their beak.   They can see colours and use their eyes to find their way around.   
Octopuses have suction cups on  their tentacles. These suction cups allow them to stick to things. But each of the many suction cups on their eight arms are like little mouths. When an octopus touches something with one of   its tentacles, its suction cups actually taste whatever it is touching.  
now do this
1 The only hard part of an octopus' body is its ...
a.  feet.
b.  beak.
c.  tentacles.
2 An invertebrate is an animal with ...
a. eight legs.
b. soft skin.
c. no backbone.
3 The female octopus dies after ...
a. hatching her eggs.
b. mating.
c.  raising her babies.
Answers:
September 23
1. b, 2. a, 3. a



Octopus