King Of Gore: Super Predator Cousin Of T. Rex Found In Utah
November 7, 2013

King Of Gore: Super Predator Cousin Of T. Rex Found In Utah

Alan McStravick for - Your Universe Online

You may have noticed your local paleontologist has had an extra bounce in his step this week. That might have something to do with a monumental find of a new super-predator dinosaur in the Wahweap Formation within the Grand Staircase-Escalante National Monument in south-central Utah. Known as Lythronax argestes, this super predator lived 80 million years ago and is a distant, older cousin to the larger Tyrannosaurus rex.

Measuring almost 30 feet in length, L. argestes (translated: King of Gore) was the largest predator of its day. The findings have been published in the journal PLOS One and the team hopes this new discovery will yield valuable insight into what the climate was like towards the end of the age of dinosaurs.

"It's always exciting to find new species but what's really significant is what these species tell us about their ancient world," said Randall Irmis, co-author of the study at the Natural History Museum of Utah. "This was a very different place 80 million years ago. It was a very lush, wet, tropical environment and there were no polar ice caps at the time."

The discovery first occurred four years ago when a partial skeleton and bones from the skull and rest of the body were unearthed. They have been the focus of intense study in the lab since that time.

As noted above, L. argestes is very closely related to T. rex. One of the important findings from this discovery is how the two great beasts shared similar features, proving that evolution occurred 10 million years earlier than had been previously thought.

Possessing a short and narrow snout and forward slanting eyes, its head was, like its T. rex cousin, full of sharp teeth allowing it to be a formidable predator, the largest of its ecosystem. Adding to its ferocity was the fact L. argestes possessed binocular-style vision.

Speaking to this trait, Joseph Sertich of the Denver Museum of Nature and Science explained the binocular vision was a direct result of the fact L. argestes possessed a very wide rear skull.

"One of the things that makes T. rex different from other dinosaurs is that it is able to look forward, it has binocular vision. Lythronax had that feature as well, its field of view could overlap which probably made it a better hunter," Dr Sertich told Melissa Hogenboom of BBC News. "It was the apex predator of its time. It was the oldest advanced Tyrannosaur of its group, which is quite surprising.

"This is the tip of the iceberg. It's amazing what we're finding in southern Utah right now. You can walk over some of the hills and find fossils littering the sides of the slopes," he added.

At the same time as this discovery, the team unearthed the most complete fossils of another member of the Tyrannosaur family – Teratophoneus curriei. T. curriei had been discovered previously, as a few skull bones had been found. However, the team has been able to complete more than 70 percent of its skeleton.

"There's a whole diversity of different branches of the Tyrannosaur family tree that are waiting to be found out there," Irmis told BBC News.

The Laramidia, a narrow strip of swampy, humid land in what is now western North America, has been the final resting place for many in the Tyrannosaurid species. Because these gigantic animals were able to move about freely, the large conflagration of these beasts in one area has been particularly baffling to scientists. The current prevailing theory is that these dinosaurs were practically confined to this region due to fluctuations in sea level.

"We think that when the sea level was high it was isolating areas in western North America that caused different species to evolve in isolation and that's why we're finding so many different species," stated Irmis.

"Tyrannosaurids were the really large predators in their ecosystem. It's fairly certain based on what we can see on their skull, teeth and body size they probably ate whatever they could fit in their mouths," added Irmis.

And so it is news like this that can excite a scientist and spark the interest and imaginations of lay people. For everything we know, we should be ever more intrigued by what we do not know but could learn tomorrow.