Tiny ancestor is T. rex blueprint

dlofnep

A 3m-long dinosaur fossil from China which predates T. rex by 60 million years is a blueprint for the mighty carnivore, say researchers.

They tell Science magazine that the fossil displays the same features as T. rex but in miniature.

The new species, Raptorex kriegsteini, would have weighed around 65kg; its descendants were 90 times as massive.

Scientists believe it could be the "missing link" between earlier species of dinosaur and T. rex.

The 125-million-year-old specimen suggests that T. rex's characteristic big head with enhanced jaw, relatively small forearms and huge back legs were inherited from this much smaller dinosaur, and that the body type changed little over millions of years except in size.

http://news.bbc.co.uk/2/hi/science/nature/8259902.stm

Galvasean

Raptorex meaning 'King of thieves'.
Somebody had better tell Kevin Costner!



Quite interesting that the 'classic' tyrannosaur features appeared so early in their liniage. The fact that they first occured in such a small animal throws another wrench in the works for Jack Horner's T.rex scavenger theory, since it relied on the (now disproven) fact that tyrannosaurs evolved their little arms after becoming massive (along with other discredited pieces o evidence.
Also, we have to completely change the tyrannosaur evolutionary tree:

It would seem the relatively long armed, three fingered Eotyrannus, which lived in Europe is more of an off shoot from the family rather than a direct ancestor of T.rex.
So, to correct the above chart, Dilong should be removed as recent research places it outside of the tyrannosauroid family (it is still however a coelurosaur) and Raptorex should be placed on it just before the paths for Eotyrannus and the larger tyrannosaurs diverge.

Raptorex skeleton:


I also really like the artwork showing up in the papers: