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Taken from the Times Globe,
Monday, June 21/99
Scientist
find shark-infested waters Rare Discovery:
The oldest complete shark fossil in the world, found near Atholville 3 years
ago, finds its way to world experts on early fossil fish
 Randy
Miller, a curator at the New Brunswick Museum, holds part of the oldest
fossilized complete shark skeleton in the world.
By Erin Dwyer Times Globe
staff writer
New
Brunswick Museum geologist Randy Miller knew from the moment he examined the
fossil closely that he had a rare find. The piece of rock
that a student discovered on this expedition didn't just contain another
fossilized shark's tooth. Many samples of these and other fish remains had been
found in the Devonian rocks near Atholville ,since the late
1800s. Looking at the area where it came from, Dr.
Miller, curator of geology at the Saint John-based museum, realized that he and
his team had found something special. He later learned it would be the oldest
complete shark fossil in the world. Last week the find -
made nearly three years ago - was presented to world experts on early fossil
fish gathered in Flagstaff, Arizona by two of Dr. Miller's
colleagues. Scientists from around the world got a chance
to see the 395-million year-old fossil, which represents about one-third of the
body of the shark. Earlier fossilized scales and denticles belonging to sharks
have 'been found, but until now the oldest ,relatively complete shark that has
been described is a 382-million-year old specimen found in
Antarctica. "We came across the specimen which is unusual
in that sharks usually fall apart when they fossilize, the teeth .and the
scales and things disarticulate and they get scattered through the sediment and
that's usually what you ,find," Dr. Miller said yesterday in an
interview. "So the earliest sharks are only represented
by scales and this specimen is relatively complete for a shark fossil.
" It was July, 1997, and Dr. Miller, two students and his
six-year-old son were in the Atholville area to re-examine sites where
significant fossil 'finds had been made more than a hundred years ago. Dr.
Miller was hoping the expedition would boost the museum's collection since most
of the specimens collected there earlier in the century had been donated to the
Scottish Museum in Scotland and the British Museum in
London. The team had split up. Dr. Miller and his son
were poking through rocks in one area when summer student Jeff McGovern came
across something unusual. "He came strolling over with a
big grin on his face and said, 'We haven't seen one of these before' and I
guess he wasn't exactly sure what it was," Dr. Miller
said. "Then we puzzled over it for a minute and looked at
it and it was the part of the jaw, and I took out the magnifying glass and I
could see the teeth in the jaw. We had already found the teeth so we knew that
there were sharks there; we knew what we were looking for but they are so rare
that we didn't expect to find one. "I went over and
looked at it, and sure enough you could see the gill slits lined up in the
little v-shaped patterns in the sediment. So we spent the next few hours
excavating this. It was pretty neat actually. We didn't expect to see one that
was held together like this because we knew that they are pretty rare.
" The shark would have measured about half a metre long
and likely lived in a low-saline estuary or lagoon. Looking at the fossil, you
can see teeth still intact in the jaw, gill slits and the scales that made up
the texture of the shark's skin. The fossil, which is
about 10- to 15-million years older than the Antarctica specimen, provides
another piece of the puzzle in the evolution of the
shark. "Anything we learn pushes things back a little
further," he said. Dr. Miller said this fossil does shed
new light on the evolution of the shark. It indicates the shark had spines
along its pectoral fins - fins located on either side of the shark and used to
steer. "This may well be the first occurrence of a paired
spine," he said. "Little details like this by themselves
don't sound like much but they are all sort of little details about what did
sharks evolve from and what did they have in their early stages. What sort of
features did they have?" Scientists will also be able to
look at its association with other fish and scorpions from the Devonian
period. "Sometimes you find specimens in museum drawers
that you don't know what they were collected with," he said. "In this case, we
collected it and so we know exactly where it was. " In
fact, it was found about a metre away from the fossilized skeleton of a big sea
scorpion, which would have looked similar to a two-metre long
lobster. Dr. Miller has a preliminary theory on the close
proximity of the two fossils, one that will require more study. He said the
scorpions could have travelled to the lagoon or back water to molt - shed their
skin - much like lobsters do today. "It may be a time
when they are fairly vulnerable," he said. "It could be that the sharks were
there because it was feeding time.
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