Coelacanth: Oldest fish gets new research

Loren Coleman lcolema1 at maine.rr.com
Fri Feb 22 11:14:12 EST 2002


via http://www.lorencoleman.com
____________________________


Canada
National Post
February 18, 2002

Oldest fish gets new research
300 million years old: Ancient coelacanth 'makes us question all the science
that has gone before'

Corinna Schuler
National Post

JOHANNESBURG - A team of international scientists will soon converge in
South Africa to mount a massive deep-sea study of "the living fossil"-- a
monstrous four-finned fish that has apparently avoided the pressures of
evolution for more than 300 million years.

Imagine a prehistoric beast of human-sized proportion that fertilizes eggs
the size of tennis balls, has bony scales, a prickly spine and four fins
that look like legs. Scientists believe the coelacanth (pronounced
seal-uh-cant) has looked just like that ever since dinosaurs roamed the
Earth, refusing to adapt or die.

"This is the world's slowest-evolving fish. How can a creature exist for
that long without changing?" asks biologist Tony Ribbink of the South
African Institute of Aquatic Bio-Diversity, which will lead the study.

"It makes us question all the science that has gone before. This animal
should be extinct. I want to know if the enigma can be explained."

Researchers from Germany, Singapore, the United States and at least five
African countries will be using a submersible vessel in a joint effort to
unlock the secret of the coelacanth.

This swimming beast has been the subject of scientific fascination since
1938, when a South African fishing trawler accidentally snagged one in its
net and handed it to a local museum for inspection.

It was like discovering a living dinosaur. Until then, scientists thought
the fish had been extinct for 70 million years and it was hailed in
newspaper headlines around the world as the greatest zoological find of the
century.

Scientists offered financial rewards to anyone who found another such
creature. Divers died trying, fisherman trolled the seas and researchers
embarked on costly expeditions up the African coast.

But it was another 14 years before the next coelacanth was discovered, in
the Indian Ocean, off the Comoros islands.

Though the species has since been located in the waters off four other
countries -- Mozambique, Madagascar, Kenya and Indonesia -- it has proven
difficult to study because coelacanths usually skulk in underwater caves up
to 600 metres below the ocean's surface.

The fish is sensitive to temperature changes and can not be brought to the
surface.

Researchers received new hope, however, in October, 2000, when a 31-year-old
lawyer spotted something strange while on a recreational dive at the St.
Lucia marine reserve on South Africa's east coast.

"I saw this eye reflecting towards me and that made me curious," Pieter
Venter said in an interview yesterday. "I approached ... and underneath a
rock overhang, I saw this fish about two metres long. It was so weird, like
from another world."

After a few stunned moments, Mr. Venter realized it was a coelacanth. He and
two friends were 104 metres below the surface -- an extraordinary depth for
divers, but the shallowest at which the fish has ever been sighted.

Mr. Venter and his diving buddies were thrilled, but none of them had a
camera. "It was like seeing a UFO without being able to take a photograph,"
he said.

The group returned with a team of six others the following month, descended
to 115 metres and, with just three minutes remaining before they would have
to ascend, they spotted three more coelacanths. This time, the divers
captured the living fossil on film.

But the great find came at a terrible price.

One diver passed out and another, Dennis Harding, tried to rescue the sick
man by carrying him back up to the surface. He ascended too quickly, and
34-year-old Mr. Harding died of a cerebral embolism on board the dive boat.

Despite the tragedy, the coelacanth discovery was huge news in South Africa.
The government immediately put the area off limits to other divers while
excited researchers spent the next year trying to raise money and necessary
permissions for a study.

Several plans fell apart before the Ministry of Science and Technology
announced last week it would provide about $2-million for an international
research project led by Mr. Ribbink. The German government is supplying a
two-person submersible vessel, and other countries are lining up to get
involved.

An initial research ship is going out "any day now" to map more than a dozen
canyons on the ocean floor. Once that is done, scientists will plot a path
for the submersible vessel and use it to establish just how many coelacanths
are living in South African waters. They hope to study the fish in its
natural environment, examine its DNA and, eventually, use it to attract
tourists.

"The educational aspect is very important," says Mr. Ribbink. "We can use
this fish as an icon of bio-diversity and encourage kids to get interested
in science.

"If we find a lot of them down there, that opens up the potential for
tourist submersibles. It would be like an underwater Land Rover."

cschuler at iafrica.com
http://www.nationalpost.com/


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