Common Octopus: The Original Ink-jet Artist!

8 arms and as many defenses!

Its first—and most amazing—line of defense is its ability to make itself invisible by using a network of pigment cells and specialized muscles in its skin to change the colors, patterns, and even textures of its skin, so as to match the surroundings. Predators such as sharks, eels, and dolphins swim by without noticing the inconspicuous octopus.

It can also adopt striking colours and patterns as warning signs - bright red shows anger, yellow with blue rings advertises that it’s poisonous, and so on.

If it has to make a fast getaway, it jettisons water from the end of its mantle, to propel itself like a torpedo through the water - headfirst, arms trailing behind.

Since it has no hard parts in its body, it can squeeze itself into tiny cracks and crevices.

If these fail, it can turn itself black just before releasing a blob of black ink which hangs in the water looking much like the body of the octopus. At the same time, the octopus will switch from black to white again and jet away, while the predator remains focused on the black blob, not noticing the white creature making the getaway in classic James Bond style!

Still another weapon is a substance in the ink that dulls the predator's sense of smell.

If all of these fail, an octopus can lose an arm to escape a predator's grasp and re-grow it later with no permanent damage.

And last, its beak-like jaws can deliver a nasty bite and release venomous saliva, though this is used mainly for subduing prey.

During the day, the octopus remains in its den, in the crevices among the rocks on the seabed. At dusk, having spotted crustaceans or fish passing by, it darts out, grabs the victim with its arms, and then brings it up to its jaws located where the arms meet, biting into the prey and flooding the wounds with poisonous saliva that immobilizes it. The pieces of food are pulled into the body by rows of tiny tooth-like structures and then swallowed.

Octopuses can survive out of water for short periods, as long as their gills stay wet. In experimental laboratories, they've been known to climb out of their tanks at night and eat the shellfish from other tanks.

Octopuses only mate once during their short 18-month life. The male octopus attracts a female by displaying a new colour and lifting up his arms to reveal the large suckers underneath. He uses a spoon-like cavity on the tip of his third arm, to transfer sperm to the female's mantle cavity.

A few weeks after mating, the male deteriorates and dies. The female lays clusters of grape-like eggs, attaching them to the walls of a crevice on the seabed. She remains with her eggs until they hatch, not eating all this time, and dies just when the eggs are hatched in a few weeks.

The newly hatched baby octopuses live part of their lives as tiny, free-floating plankton, most being eaten by predators. The few that survive, get big enough to settle into a bottom-dwelling lifestyle.

Considered the most intelligent of all invertebrates, they are said to be as intelligent as dogs. They are known to collect crustacean shells and other objects to construct fortresses around their dens - no wonder they have real blue blood!

If an octopus ever squirts ink at you, don’t even bother to shout out, “Hey! Have a heart!” He’s stone-deaf and it’s just as well… he has three hearts!

Copyright © 2007 Noël Gama
www.noelgama.com