The latest issue of science journal reports a new discovery, a 9-foot dinosaur fossil from northeastern China by Paul Sereno and colleagues.This new fossil is named “Raptorex kriegsteini” , displays all the features of giant Tyrannosaurus rex and it predates the T. rex by tens of millions of years.

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. The huge head, the powerful jaws bristling with long teeth, the magnificent tail, and the stubby arms of T . rex can also be observed in the newly discovered fossil of Raptorex but it was only one-fifth of size.

In The Image : T . rex and Raptorex

Credit : Drawing by Todd Marshall

Caption : Weighing as little as 1/100th that of its descendant T. rex, 125-million year old Raptorex shows off the distinctive body plan of this most dominant line of predatory dinosaurs. This is based on a fossil skeleton discovered in Inner Mongolia, China.

For decades scientists were of the opinion that these traits, along with the creature’s enormous olfactory capability, evolved from a less specialized but similarly sized version of T. rex. But with the uncovering of this miniature version of T .rex in Raptorex changes all that , which represents a blue print for what will go on to become a huge monstrous T .rex 60 millions years later. According to researcher Paul Sereno , Raptorex belongs to an early side branch of the evolutionary group that gave rise to T. rex .

Reference :

Tyrannosaurid Skeletal Design First Evolved at Small Body Size.
Sereno PC, Tan L, Brusatte SL, Kriegstein HJ, Zhao X, Cloward K.
Science. 2009 Sep 17.

Related Posts:

• New species of Dinosaur discovered in Gobi desert – Psittacosaurus gobiensis
• Discovery of four-winged Dinosaur fossil in China
• New fossil from Chengjiang Lagerstatte : Luolishania longicruris
• Fossil Paradise
• Evolution of ear in mammals: Discovery of New animal

SHARE THIS ARTICLE