Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A tiny tyrannosaur

21.09.2009
Small fossil described in Science predates the T. rex

When you think of Tyrannosaurus rex, a small set of striking physical traits comes to mind: an oversized skull with powerful jaws, tiny forearms, and the muscular hind legs of a runner.

But, researchers have just unearthed a much smaller tyrannosauroid in China, no more than three meters long, that displays all the same features – and it predates the T. rex by tens of millions of years.

This finding, published online by the journal Science at the Science Express website on September 17, means that such specialized physical features did not evolve as the prehistoric predators grew in size. Instead, they were present for feeding efficiency at all sizes of the dinosaurs during their reign in the Cretaceous Period.

Paul Sereno from the University of Chicago and National Geographic explorer-in-residence, along with colleagues, studied the new, small-bodied fossil, naming it Raptorex kriegsteini, and estimated that it was a young adult when it died. They examined the skull, teeth, nose, spine, shoulders, forearms, pelvis, and hind legs of the new fossil, comparing the features to larger evolutionary versions of tyrannosauroid dinosaurs.

"First, we used the best mechanical preparation of the specimen possible, which entails the finest needles and air abrasives under a microscope," Sereno said in an email interview. "Then we made molds and casts of the cranial bones, assembled a cast skull, and sent that skull through a CT scanner at the University of Chicago hospital to get the snout cross-section… We used silicone on the skull roof to cast the forebrain of R. kriegsteini… Finally, I made a thin-section from one femur, or thigh bone, for microscopic examination, and determined that the individual had lived to be five or six years old."

The researchers conclude that the "predatory skeletal design" of R. kriegsteini was simply scaled up with little modification in its carnivorous descendants, whose body masses eventually grew 90 times greater.

Sereno and his colleagues also use this new fossil to propose and describe three major morphological stages in the evolutionary history of tyrannosauroid dinosaurs.

Dr. Sereno's coauthors are Lin Tan of the Long Hao Institute of Geology and Paleontology in Hohhot, PRC; Stephen Brusatte of the American Museum of Natural History in New York, NY; Henry Kriegstein of Higham, MA; Xijin Zhao of the Chinese Academy of Sciences in Beijing, PRC; and Karen Cloward of Western Paleontological Laboratories, Inc. in Lehi, UT. The paper is entitled, "Tyrannosaurid Skeletal Design First Evolved at Small Body Size."

This research was funded by the David and Lucile Packard Foundation and the National Geographic Society.

The American Association for the Advancement of Science (AAAS) is the world's largest general scientific society, and publisher of the journal Science (www.sciencemag.org). AAAS was founded in 1848, and serves 262 affiliated societies and academies of science, reaching 10 million individuals. Science has the largest paid circulation of any peer-reviewed general science journal in the world, with an estimated total readership of 1 million. The nonprofit AAAS (www.aaas.org) is open to all and fulfills its mission to "advance science and serve society" through initiatives in science policy; international programs; science education; and more. For the latest research news, log onto EurekAlert!, www.eurekalert.org, the premier science-news Web site, a service of AAAS.

Kathleen Wren | EurekAlert!
Further information:
http://www.aaas.org

More articles from Earth Sciences:

nachricht NASA examines newly formed Tropical Depression 3W in 3-D
26.04.2017 | NASA/Goddard Space Flight Center

nachricht Early organic carbon got deep burial in mantle
25.04.2017 | Rice University

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

Scientist invents way to trigger artificial photosynthesis to clean air

26.04.2017 | Materials Sciences

Ammonium nitrogen input increases the synthesis of anticarcinogenic compounds in broccoli

26.04.2017 | Agricultural and Forestry Science

SwRI-led team discovers lull in Mars' giant impact history

26.04.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>