duminică, 31 august 2008

Octopuses Don't Have Eight Legs

Not Just Arms, Legs Too
Not Just Arms, Legs Too

- How many legs does an octopus have? The answer should be easy. But not any more.

For new research suggests they are not really eight-legged denizens of the deep, as popularly assumed; instead they use their front limbs more like arms -- and can even tackle a Rubik's Cube.

Octopuses use their back two limbs largely for propulsion and use the front six for a variety of tasks, with the front two doing most of the exploratory work, said Alex Gerard, the curator of the Sea Life center in Brighton on the southern English coast.

Some 16 Sea Life center aquariums across Europe in Britain, Germany, Belgium, Finland, Ireland and the Netherlands studied their Giant Pacific, Common and Lesser Octopuses in coordinated tests.

"We've found that in all the tests, they do tend to favor particular limbs, which tends to give them a legs and arms sort of layout," Gerard told AFP Wednesday.

"Their front two tentacles will be used for a lot of exploratory work and then the ones immediately behind them will then be used also if further investigation is needed.

"Then the further back you go, the more the limbs are used for propulsion and movement.

"From what we've seen, all the limbs basically have the same capabilities. But they seem to favor this system and it works well for them.

"With live prey it does help them when sneaking up, with the front limbs ready to pounce and using the back ones for propulsion," he explained.

"They have that facility, unlike humans where if we tried to grab our food with our feet we might fail miserably."

However, he does not believe octopuses -- named after the ancient Greek for eight footed -- will have to be give a new name.

"The name's pretty good and they would have to rename James Bond movies," he said.

He added that though, like humans, some favor their left or right limbs more, "it just seems to be an individual preference".

Gerard conducted tests on Popeye, a Lesser Octopus at the Brighton center.

"Octopuses do have very strong personalities. They do develop their own favorite toys," he explained.

"My octopus hates the color red -- that's quite a natural response in nature -- but he particularly likes yellow. We're starting to build a profile for different octopus," Gerard added.

And during the tests, the octopuses got to play with some particularly challenging toys, namely Rubik's Cubes -- though none have managed to solve one yet.

"A happy octopus is one that's being constantly entertained," Gerard said.

"We wanted objects that would withstand an octopus exploring it but would also stimulate them. Things that were colorful were helpful.

"With a Giant Pacific Octopus, which is largest species in the world, it had ability to move sections of the Rubik's Cube."

The results are expected to be finalized and published in scientific journals.

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