22 noviembre 2013

Who terrorizes the tyrannosaurs ?


A newly discovered dinosaur is believed to have been more than a match for the relatives of T. rex. Known as Siats meekerorum, the 40ft long meat eater lived around 98 million years ago and would have been a formidable rival to any other predatory dinosaurs of the time. Living 30 million years before Tyrannosaurus rex, Siats is believed to have dominated its ancestors long before the tyrant lizard itself appeared on the scene. "Contemporary tyrannosaurs would have been no more than a nuisance to Siats, like jackals at a lion kill," said study leader Dr Lindsay Zanno.

"It wasn’t until carcharodontosaurs like this bowed out that the stage could be set for the evolution of T. rex." Fossil bones of Siats were discovered in the Cedar Mountain Formation in Utah and appeared to belong to a juvenile measuring approximately 30ft in length. It is believed that the species would have mostly hunted slow moving herbivores and that it may have fought off rival predators to secure its kills.


 "It has been 63 years since a predator of this size has been named from North America," said Dr Zanno. "You can’t imagine how thrilled we were to see the bones of this behemoth poking out of the hillside."

Source and credit a unexplained-mysteries