'Zombie' worms found in North Sea shallows

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The Independent Online

The worm belongs to a new class of marine organism that has made a speciality out of scavenging on the huge carcasses of whales. Scientists were amazed to have found an entirely new species in an area of the ocean that they considered to be one of the most intensively studied marine habitats.

"We were astounded to discover a species completely new to science in an environment that is so well known," said Adrian Glover, a marine biologist at the Natural History Museum in London.

"It is amazing that discoveries of novel organisms are being made even right on our doorstep. You don't have to spend billions sending people into space, or even the deep sea, to discover new species and throw up new scientific questions," he said.

Dr Glover and Thomas Dahlgren of Goteborg University in Sweden found the new worm on the bones of a dead, stranded minke whale they had towed out to sea before dropping to a depth of 120 metres.

They studied the decomposition of the carcass using a remotely-operated submersible.

After hagfish had stripped the bones of flesh, the scientists found the bared bones were soon colonised by the worm, which they have called Osedax mucofloris, which means bone-eating snot flower.

"We sometimes called them snot worms because when they retreat into their tubes they leave mucus behind which is probably a defensive mechanism," Dr Glover said.

Last year, scientists in America found similar organisms feeding on the bones of dead whales buried at depths of 2,500 metres, which they nicknamed "zombie worms". But the species living in the North Sea is genetically distinct from the species discovered off the coast of California, according to a study published in the journal Proceedings of the Royal Society B: Biological Sciences.

There are remarkable similarities between the two species of worm despite being so far away. Both worms use root-like appendages to burrow into the bone where they feed on whale oil stored within the bone cavities, Dr Glover said.

"The worms have bacteria in their tissues which they use to degrade the oil to produce energy," he said. "Osedax has no mouth or intestines and derives all its food from these symbiotic bacteria that the worm has somehow managed to acquire during its development," Dr Glover explained.

The family

* The new worm belongs to a group called the Annelids, which includes the common earthworm

* It is believed the new species is related to tube worms that live near deep-sea vents called "black smokers". Those worms can grow up to six feet long

* In an acre of land there can be a million earthworms, each can eat its own body weight a day.