Posted on 10/06/2004 2:08:54 PM PDT by PatrickHenry
Ancestors of the fearsome Tyrannosaurus rex were clothed in delicate feathers, a fossil discovered in China suggests. The find may come as a surprise to people used to images of Tyrannosaurus as a scaly monster. But many palaeontologists have been predicting just such a find ever since the first evidence of a dinosaur with a feathery coat came from the same site in Liaoning in 1995.
The 130 million-year-old fossil is the oldest member recorded from the tyrannosauroid family, and the first in the group with a feather-like covering. The discovery of its skull and other fragments is reported today in Nature1.
The new dinosaur has been christened Dilong paradoxus. Dilong means Emperor dragon. "We added paradoxus to its name because it's so counter-intuitive to think of feathers and a Tyrannosaurus together," says team member Mark Norell at the American Museum of Natural History in New York city.
Evidence of these so-called protofeathers is usually difficult to find because feathers decay when they are exposed to oxygen. But at Liaoning, the specimens appear to have been buried extremely quickly under fine-grained volcanic ash, helping to preserve the soft, feathery outlines.
"Dilong is an exciting find because it's so complete," says palaeontologist Thomas Holtz of the University of Maryland in College Park, "and the feathers are the icing on the cake."
Holtz hopes that the new evidence will convince the scientific community that feathers evolved on dinosaurs long before the appearance of birds. Until now, some palaeontologists have been dubious that feathered tyrannosauroids existed.
Feathered and petite
The jackal-sized Dilong was far smaller than T. rex, which roamed the Earth some 65 million years later. But Dilong shares many of its characteristics.
The meateater probably had a broad, square skull and powerful jaws, says Holtz. But while the forelimbs of T. rex had dwindled until they were almost useless, Dilong would have been able to clutch food in its hands and bring it to its mouth.
Dilong's protofeathers are not what we would recognise as feathers today, but are their evolutionary precursors. Rather than having a central shaft and barbs, they are single flexible filaments that would have covered the dinosaur's body like hair.
The protofeathers would most likely have been used for insulation rather than flight, Norell says. The giant T. rex had probably lost the featherlike features of its predecessors because, with its much larger size, it would have had more difficulty losing heat than keeping it. Tyrannosaurus chicks may have had a downy cover, though.
However, the discovery of feathered dinosaurs at Liaoning is trickling down into popular culture. The first Jurassic Park film featured mainly scaly reptiles, Norell says, "But from what I've seen of the first shots of Jurassic Park IV, all the dinosaurs now have feathers."
[From PH:] The article has a small sketch, but no pics. The footnote in the article is this: Xu X., et al. Nature, 431. 680 - 684 (2004). And in the original artice there's a link to the Letter in Nature.
They dug up one of Theresa Heinz Kerry's relatives??
Now you've gone and done it.
I'm puzzled. The description of the protofeathers sounds like hair, not feathers.
Tyrannoducken for Thanksgiving!
"Transitional species" ? LOL!
No evidence backs that up. It's just someones imagination at work trying to convince the sheeple to believe in "evolution".
Maybe my cat will morph into a bird soon too! LOL!
Its critical that we save this endangered species. Global warming is bound to kill it off. It lives in wetlands. Bush is responsible for all this.
I'd love to have one of those little criters for my backyard.
LOL! ...
Well, it is tall, and apparently has good hair, I wonder about it's debating skills....
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It'll never fly, you shouldn't waste your time.
> It's just someones imagination at work trying to convince the sheeple to believe in "evolution".
My congratulations on an excellent satire of the usual Creationist claptrap.
ahhhhh,
I want one!
That's one hell of a turkey shoot.
Archaeopteryx is still older. Stated before, anything found in this formation will still be younger than a fully feathered Archie.
You are correct on both points. Protofeathers probably served a similar function as hair in thermoregulation.
OK, how do I field dress it?
Featherlike coverings were probably pretty widespread in at least the smaller-sized theropod dinosaurs. So far, only a few fossilization sites have allowed the kind of preservation which would let us see such detail. This paucity of feather evidence has allowed skepticism of the whole idea, but here's another example for a subgroup not previously found with feathers. The more subgroups that have them, the farther back down the tree you put the common ancestor that first grew them.
One reason this matters, the somewhat older Archaeopteryx from limestone deposits in Europe had a dinosaurian skeleton (apparently closely related to some of the Liaoning China species) but a very impressive set of feathers. Today's find makes it easier to state that many of Archy's contemporaries were also feathered. (We just don't have well-enough preserved fossils for all of them.)
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It's just as well they're extinct. What with the hurricanes, the earthquakes, and the volcanoes, the last thing we need right now is flying meat-eaters the size of tractor-trailers.