- Life for the red sea urchin might be brutish but it certainly
is not short: scientists have discovered the spine-covered creature can
live for 200 years.
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- The urchins live in shallow waters off America's west
coast. Thomas Ebert, a marine biologist at Oregon State University, said:
"These red sea urchins appear to be practically immortal. They can
die from attacks by predators, specific diseases or being harvested by
fishermen but even then they show few signs of age. The evidence shows
a 100-year-old red sea urchin is just as apt to live another year, or reproduce,
as a 10-year-old sea urchin."
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- Scientists thought the urchin lived for 10 or 15 years
until they measured levels of radiocarbon 14, an element that increased
significantly in all living organisms after the atmospheric A-bomb tests
of the 1950s. The study found the urchin grew at a steady rate independent
of changes in the marine habitat. "Once they near adult size our research
indicates they do not have growth spurts," Dr Ebert said. "It's
pretty simple; the bigger they are, the older they are." The researchers
also found urchins never stopped growing. Some of the largest are 19cm
(7.5in) across. "They are probably 200 or more years old," Dr
Ebert said.
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- Red sea urchins live on seaweed. "People believed
they were at least partly responsible for the decline of that marine ecosystem,"
Dr Ebert said. In the 1970s, the red sea urchin became valuable when fishermen
realised the urchins' sex organs were considered a gourmet delicacy in
Japan.
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- © 2003 Independent Digital (UK) Ltd
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- http://news.independent.co.uk/world/science_medical/story.jsp?story=467010
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