'Zombie' Worms Found in
North Sea Shallows
10/19/2005
The Independent (London, England)
By Steve Connor Science Editor
A bizarre species of 'zombie' worm that feeds on the bones of dead whales
has been discovered living in the relative shallows of the North
Sea.
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
1) The new worm belongs to a group called the Annelids, which includes the
common earthworm.
2) 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.
3) In an acre of land there can be a million earthworms, each can eat its
own body weight a day.
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