First-ever adult T. rex trackway found in North Dakota
Paleontologists have identified the first known trackway made by a full-grown Tyrannosaurus rex, and the discovery was made in the North Dakota badlands.
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Paleontologists have identified the first known trackway made by a full-grown Tyrannosaurus rex, and the discovery was made in the North Dakota badlands.
The Dinosaur National Monument, which is located on the border between Colorado and Utah, was last excavated in 1924.
Most of the footprints are elongated and made by bipeds. The best-preserved ones bear traces of at least four toes.
Paleontologists have discovered and documented 16,600 footprints left by theropods, the dinosaur group that includes the Tyrannosaurus rex.
The discovery "rewrites decades of research on Earth's most famous predator," the study's co-author said.
The new find was possibly 23 feet long and hailed from a mysterious group of dinosaurs called megaraptorans.
Apex predators, like the Tyrannosaurus rex, eventually arose from smaller-bodied tyrannosauroid dinosaurs called Khankhuuluu mongoliensis, the study's researchers said.
The dinosaur fossil of a Stegosaurus nicknamed Apex fetched 10 times its estimate at a Sotheby's auction on Wednesday.