Surfing The Wierd

Saturday, October 31, 2009

Earlier, Smaller Version of T.Rex Found

http://news.nationalgeographic.com/news/2009/09/090917-tiny-t-rex-dinosaur-raptorex.html (photos in article below first)

Tiny "T. Rex" Found -- 150-Pound Species Came First

Rebecca Caroll for National Geographic News
September 17, 2009

If dinosaur evolution were an Austin Powers movie, T. rex would be Dr. Evil. And today scientists unveiled Mini-Me.

But in this case, it was the tiny terror that gave rise to the larger, more infamous relation.

Raptorex kriegsteini, described this week in the journal Science, likely lived about 125 million years ago, during the Cretaceous period.

That's almost twice as far back as the mighty Tyrannosaurus rex, which first arose about 85 million years ago, according to study leader Paul Sereno of the University of Chicago.

Raptorex has all the main characteristics of its larger descendants such as T. rex—big head, nipping teeth, stubby arms, fast legs—but packed into a 9-foot (3-meter) frame.

This T. rex design in miniature "reveals a spectacular carnivore strategy," according to Sereno, a National Geographic Society explorer-in-residence. (The National Geographic Society owns National Geographic News.)

(Read National Geographic magazine editor Chris Sloan's take on Raptorex.)

Tiny T. rex "Evolutionarily Staggering"

The 150-pound (70-kilogram) Raptorex "was running things down, dispatching them with its powerful jaws, and clutching them with its two-fingered hands"—the same hunting strategy that apparently worked for 6-ton T. rex, Sereno said.

"That's the pretty evolutionarily staggering thing," he added. Raptorex is T. rex, but "scaled up, almost without change, a hundred times."

The find runs counter to previous theories, which had said that T. rex's stumpy arms were a relatively recent evolutionary development. As tyrannosaurs got larger, their arms simply didn't scale up fast enough, and the limbs eventually became small in relation to the dinosaurs' oversized bodies, the older theories say.

It's still thought, however, that T. rex's earlier ancestors—even before Raptorex—had relatively long arms.

T. rex-style Arms Not a Liability

The new dinosaur is "a very significant find" for understanding the evolution of tyrannosaurs, said paleontologist Thomas Holtz of the University of Maryland.

"We didn't know where and when in the history of the tyrannosaurs this arm-shortening occurred," said Holtz, who was not part of the study.

"Now the question is going to be, What were they doing [with those small arms]?" Holtz said. "There's not much of a reach," he added, speculating that the tyrannosaurs grabbed prey first with their jaws and then used their arms to help hold onto their quarry.

Study leader Sereno noted that it can be hard for people to appreciate the trade-offs that evolution inevitably entails.

"It would seem to a human that forelimbs are so useful, that only when you got to the size of a tyrannosaur and you could frighten everybody with a growl could you get rid of [forearms]," he said.

"But this common sense type of thinking almost never works with evolution," Sereno said. In the tyrannosaurs, for instance, "long, heavy forelimbs are a significant burden and would seriously curtail agility in the hunt."

Smuggled T. rex Ancestor Heading Home

The new findings are based on a nearly complete Chinese dinosaur skeleton, which was excavated in secret, smuggled into the United States, and sold at auction to private collector Henry Kriegstein.

Sereno said he convinced Kriegstein to donate the fossil back to science.

Although the exact location the dinosaur came from will never be known, the excavated block containing the dinosaur's skeleton also included fish bones and clamshells that link it to Northern China's Yixian fossil formation.

Raptorex kriegsteini, named after the collector's father, an Auschwitz survivor, will eventually be shipped back to Northern China, where it will be displayed in a museum in Hohhot, the capital of China's Inner Mongolia region.

"Fossils like these should be protected from smugglers, or there's a chance they could disappear forever," Sereno said.

Until that day comes, Sereno hopes the story of this fossil can serve as a model for saving—and learning from—smuggled dinosaurs.

"I think everybody involved with this Raptorex is a winner here," he said.

............................... story http://news.yahoo.com/s/ap/20090917/ap_on_sc/us_sci_tiny_t_rex

Early, smaller version of T. rex found

This undated handout illustration provided by the journal Science shows a Raptorex. Weighing as little as 1/100th of its descendant T.Rex, Raptorex shows off its distinctive body plan of this most dominant line of predatory dinosaurs. About 125 million years ago a tiny version of Tyrannosaurus rex roamed what is now northeastern China. Tiny, that is, by T. rex standards — you still wouldn't want to meet it face to face. Described by paleontologist Paul Sereno as 'punk size,' this early predator stood about 9 feet tall. It just seems small compared to the giant T. rex that evolved millions of years later and was as much as 100 times more massive. (AP Photo/Science, Todd Marshall) This image released by the American Association for the Advancement of Science (AAAS) shows the two-fingered forelimb of an adult T. rex and the very similar 8-inch (20.3-cm) forelimb of Raptorex. The relatively tiny new ancestor of the Tyrannosaurus rex was unearthed in China, researchers said. (AFP/AAAS-HO/Mike Hettwer) This image released by the American Association for the Advancement of Science (AAAS) shows the skull of Raptorex dwarfed by the skull of 'Sue', the famous adult T. rex at the Field Museum in Chicago. The relatively tiny new ancestor of the Tyrannosaurus rex was unearthed in China, researchers said. (AFP/AAAS-HO/Paul Sereno)

WASHINGTON – About 125 million years ago a tiny version of Tyrannosaurus rex roamed what is now northeastern China. Tiny, that is, by T. rex standards — you still wouldn't want to meet it face to face.

Described by paleontologist Paul Sereno as "punk size," this early predator would have weighed about 150 pounds.

It just seems small compared to the giant T. rex that evolved millions of years later and was as much as 100 times more massive.

"It really is the blueprint for the later (T. rex) dinosaurs," Sereno said, "it was a blueprint that was scalable."

Described for the first time in Thursday's ScienceExpress, the online edition of the journal Science, the new dinosaur has been named Raptorex kriegsteini.

Sereno reports that Raptorex has all the hallmarks of T. rex, including a large head, tiny arms and lanky feet — just in a smaller size.

"What we're looking at is a blueprint for a fast-running set of jaws," Sereno said at a briefing arranged by the American Association for the Advancement of Science.

The giant T. rex dominated much of the planet from about 90 million years ago until the great extinction 65 million years ago.

Raptorex would have stood a lanky 9 feet tall, said Sereno, of the University of Chicago and also a National Geographic explorer in residence.

The newly described remains were found by fossil hunters in northern China, smuggled out of that country and offered for sale to collector Henry Kriegstein of Higham, Mass., Sereno said. Kriegstein, for whom the animal is now named, donated the materials to science and they will be returned to China.

The fossil was encased in a single block of stone, Sereno said. That stone allowed the researchers to trace the find to its original location.

The way the bones were fused indicates the animal died at the age of five or six, which is nearly adult. It would have matured at eight or 10 and been old by 20, added co-author Stephen Brusatte of the American Museum of Natural History.

The find also shows that features such as the animal's tiny arms did not evolve as T. rex grew larger, but were present in the much earlier forms, Brusatte said.

"Much of what we thought we knew about T. rex turns out to be simplistic or out-and-out wrong," Brusatte said.

Sereno said Raptorex was a predator. Some scientists debate whether T. rex was a predator or scavenger.

Dinosaur expert John R. Horner of the Museum of the Rockies at Montana State University was cautious about the find.

"It's hard to evaluate their conclusions," he said, calling the report interesting but adding that the drawing in the paper shows some differences from a T. rex in addition to being smaller.

However, he added, he didn't see anything that would disprove their theory that Raptorex was an ancestor of T. rex.

The research was funded by the Whitten-Newman Foundation and the National Geographic Society.

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