U of A dino hunter finds ferocious carnivore

A University of Alberta paleontologist has helped discover a new dinosaur that was likely one of the largest and most ferocious carnivores ever to have roamed the Earth.

Prof. Philip Currie and Rudolfo Coria, a paleontologist in South America, excavated a group of at least seven of the formidable predators just outside west-central Argentina's Plaza Huincul.

Buried under the region's red desert sandstone for up to 90 million years, the dinosaurs' bones are much older than those of the Tyrannosaurus rex, which lived 65 million to 70 million years ago in what is now Asia and North America.

The newly discovered dinosaur, Mapusaurus roseae, looked like the Tyrannosaurus rex but had a much bigger head. Bone fossils suggest its body was also bigger.

"The fact that it was so big was formidable enough but when you add to the fact it was a packing animal and moving in groups of half a dozen to a dozen animals, it could have taken down anything at all," said Currie, co-author of a paper about the discovery that appears in the spring edition of Geodiversitas, a journal about earth sciences.

"Like prides of lions or packs of wolves, these things probably hunted co-operatively and it wasn't just one chasing you like in the first movie Jurassic Park. It would have been a bunch of these things chasing you."

Currie said that means Mapusaurus roseae likely fed off the largest plant-eating dinosaur ever discovered the 100-tonne Argentinosaurus.

He said both dinosaurs roamed the swamps and forests of what is now Argentina 90 million years ago.

Mapusaurus roseae was first discovered in 1995 by a local rancher. Two years later, Currie and Coria arrived to lead a team that began the slow, tedious process of excavating the site.

Removing 100 tonnes of sandstone from the desert hilltop, they found hundreds of bones and were able to establish that the hilltop contained seven to nine juvenile and adult Mapusaurus dinosaurs.