It might not have had a starring role in any movies or rock bands named after it, but scientists now believe there was a species of mega-predator that roamed Earth at the top of the food chain for millions of years before Tyrannosaurus.
It's called Siats meekerorum, and a team of researchers led by Lindsay Zanno, a North Carolina State University paleontologist, and Peter Makovicky, from Chicago’s Field Museum of Natural History, discovered the dinosaur's partial skeleton in Utah in 2008. They announced their findings last week, calling it the third largest carnivore ever discovered in North America.
"They were equal and in some cases possibly surpassing the size of T. Rex," Zanno said. "It wasn't until they went extinct that tyrannosaurs were really able to take over those mega-predator roles and evolve into things like T. Rex."
Zanno said this discovery has helped scientists fill in a gap of knowledge about the types of dinosaurs that existed between two better-known periods — the Jurassic period, which ended 145 million years ago, and the Late Cretaceous period, which ended 66 million years ago.
Check out the video above for more on Siats meekerorum.
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Image: Wikimedia Commons, David.Monniaux