Posted on 03/15/2006 12:23:34 PM PST by The_Victor
LONDON (Reuters) - A newly discovered, perfectly preserved fossil of a 150 million-year-old dinosaur found in southern Germany may force scientists to rethink how and when feathers evolved.
The nearly complete remains of the chicken-size dinosaur named Juravenator, which is described in the journal Nature on Wednesday, were preserved in limestone. But unlike other members of the group of two-legged meat-eating predators known as coelurosaurs, it had no feathers.
"It is an absolutely new dinosaur that was not known before," said Ursula Gohlich, a palaeontologist at the University of Munich in Germany.
Remains of small dinosaurs from the Late Jurassic period are rare finds. The new fossil is nearly complete, apart from a missing part of its long tail, and shows soft tissue and an imprint of the skin but no feathers.
"Scientists had thought that all representatives of the group coelurosaurs should have feathers," Gohlich told Reuters.
"Now we have a little dinosaur that belongs to coelurosaurs that does not show feathers. This is a problem."
COMPLEX EVOLUTION
Feathers were thought to have evolved very early within coelurosaurs. All members of the group were thought to be feathered.
But Gohlich and Luis Chiappe, of the Natural History Museum of Los Angeles County in California, believe the evolution of feathers may be more complex than previously thought.
Feathers may have evolved early but then were replaced by scales in some creatures because they were not needed.
"Another possibility perhaps is that some representatives of coelurosaurs were not entirely covered with feathers, only certain areas," said Gohlich.
The newly discovered Juravenator was very young so may not have lived long enough to develop feathers. But Gohlich said that despite its age, she would have expected it to have had feathers.
"We think that feathers evolved. We have several fossils that support this theory. But our fossil asks some questions," she added.
The oldest known bird, Archaeopteryx, was also found in southern Germany. It too lived about 150 million years ago and had feathers but it is uncertain whether they were used to fly or to keep warm.
Xing Xu, of the Chinese Academy of Sciences in Beijing, said whatever the explanation, the discovery of Juravenator has enriched knowledge of early feather evolution. It could also indicate where future research could be concentrated.
"Juravenator may complicate the picture, but it makes it more complete and realistic," he said in a commentary in the journal.
> when new evidence tells you the overall theory may be
incorrect...
Let us know when such evidence comes along. So far, what this shows is that some *small* portion of the theory of evolution (specifically, the evolution of feathers) is not quite what was thought.
What you're proposing is like finding that someone who was thought to have been gassed at Auschwitz was actually shot at Treblinka, and then concluding that the Holocaust was a hoax.
Chalk up another superb prediction for evolution, utterly inexplicable by any creationist model other than "God did it that way to fool scientists into thinking that common descent is true".
There are some in South America but don't ask me to name them. From the Gondwonaland days.
Thanks for the ping!
Documented where? The only fake I'm aware of is the Chinese thing the National Geographic published before peer-review.
We evolved to be really good long-distance runners. One of the adaptations that helps us in this regard is less thick body-hair. We have heat regulation options that are available to few other animals.
That is why, over a long distance, there are few, if any animals, that can keep up with humans.
Is that how evolution works?
Pretty much. ET is just a bunch of goofballs sitting around telling each other stories. They get grants to do it.
I especially like the fact that there used to be big Marsupial predators, showing VERY similar traits to saber-toothed tigers.
http://www.paleocraft.com/thylacosmilus.html
Yeah, that's cool. Marsupials are fascinating to study, and Australia is a great place. I like the monotremes even more, though. They are wonderful critters. The echidna is my favorite, although the platypus comes in a close second. It's so bizarre that it's hard to even place it in the class of mammals.
Yes. Like eyeballs or wings.
Maybe our intelligent designer was not so intelligent after all? How did he miss that one?
Just makes me wish I could see a picture of it.
Who told you that? Actually, fossilized dinosaur feathers have been found in Liaoning, China.
They are like Dems, they will believe what they want and to hell with the trurh, the feather hoax continues. I am NOT a christian, NOT a creationist or IDer, just a guy who wants the truth to be told. If evolution is real, then their is no need for fakes and false claims, although they continue unabated and with no shame from the evos!
Why does that one section of Biology split from the others and the rest of science and suddenly form an airtight wall of secrecy in their bitter struggle to misinform the people of the world, all the while knowing for sure they are wrong, but persevering anyway? Money? Love? The thrill of hoaxery? The lifetime DVDs?
Afraid there are many hummers.
It's the chicks, man. They just dig a good hoaxer.
Any natualist worth his salt can do that today with all sorts of structural features..take a skull
Eyes to the front...good for the hunt.
or a footprint:
Serious claws catch meat for the maws.
No, we aren't
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