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Debate kicked off in 1988 when a single small tyrannosaur skull discovered four decades earlier was given its own species ...

“The fossil, part of the legendary ‘Dueling Dinosaurs’ specimen unearthed in Montana, contains two dinosaurs locked in prehistoric combat: a Triceratops and a small-bodied tyrannosaur. That ...

A new look at the "Dueling Dinosaurs" fossil reveals that Tyrannosaurus rex was not the only tyrannosaur roaming the land.

Researchers say they have identified a new species of Tyrannosaurus that traces the dino's lineage to North America much earlier than previously thought, and could shed new light on the murky origins ...