Mystery theropod from Argentina

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From: Ben Creisler bh480@scn.org

In case this news item has not been reported here:

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Dinosaur fossil baffles Canadian scientists
Canadian Press

CALGARY ? The discovery of a mysterious fossil on a South 
American cliff offers the tantalizing possibility of a 
whole other species of meat-eating dinosaurs, says one of 
the world's foremost experts.
"We thought it was related to the tyrannosaurus just 
because there were a lot of features in the vertebrae as 
we were taking it out," said paleontologist Philip Currie, 
who was involved in the dig, from the Royal Tyrrell Museum 
in Drumheller, Alta.
"But when we compared it to the specimens in Alberta -- we 
compared it to the giganotosaurus the carnotaurus and 
their relatives -- it doesn't add up."
There are two main types of meat-eating dinosaurs in South 
America. Both were two-legged carnivores that lived about 
80 million years ago.
But characteristics from the latest fossil don't quite 
match up, although at eight metres in length and weighing 
about a tonne, it would have appeared quite similar, said 
Currie.
"When you look at a shark verses a dolphin, they look 
quite similar in terms of body form, but of course they're 
not related at all," Currie said. "One's a fish and one's 
a mammal."
The fossil includes much of the skull and about 30 teeth, 
part of the vertebral column, hip and leg bones. One of 
the most interesting aspects is the brain case which is 
being studied at the Tyrrell.
"This is the part that envelops the brain and you first of 
all can see how big the brain was and you can actually see 
the various components of the brain preserved as 
impressions in the bones," he said.
It was Currie and Rodolfo Coria, director of the Carmen 
Funes Museum in Neuquen, Argentina, who removed the fossil 
in 2001 from the northern Patagonia region of Argentina.
The data from the discovery is being fed into a computer 
to see if it matches any other dinosaur finds, said Coria.
"We are dealing with two possible hypotheses. One is it's 
a new kind of dinosaur, a large size of meat-eating 
dinosaur that was not recorded before," Coria said. "Or 
it's a very specialized version of the other two ones that 
we already know.
"Whatever it is, this is very exciting because we are 
learning a lot of things we didn't know about dinosaur 
evolution in Patagonia from this guy." 
The similarities between the Argentinian fossil and that 
of fossils of Albertosaurus, a type of tyrannosaur found 
in southern Alberta's Badlands, raise questions of how 
dinosaurs living in isolation from each other developed 
remarkably similar characteristics. 
"What we're thinking now is these animals developed 
independently but they were responding to the environment 
the same way," said Currie. "It's possible that because 
they both were quite large, they had a similar response 
and ended up looking quite similar without actually being 
related."
There were also similarities to the climate and landscape 
in northern Patagonia and the Alberta of 80 million years 
ago, Coria pointed out.
"The weather was very arid. It wasn't a jungle or a place 
with a lot of wet and heat. It was very similar to 
Alberta . . . with a lot of streams and rivers and room 
enough for all these gigantic forms of dinosaurs."