Young T-Rex or New Dinosaur? New bones add to the discussion

Scientists have long wondered about the origins of a mysterious dinosaur unearthed in the 1940s: Was it a young T. rex or another type of dinosaur?

At first, researchers only had one tyrannosaur skull to go by, making it difficult to tell whether it was from a child or an adult. Another skull and skeleton named Jane added to the debate, but did not resolve the controversy.

Now a research team says it has new evidence that solves the case. The latest clue comes from a complete skeleton — previously unearthed in Montana in 2006 — that scientists say has identified the mystery reptile as its own species and not a juvenile Tyrannosaurus rex.

Study co-author Lindsay Zano, with the North Carolina Museum of Natural Sciences and North Carolina State University, said the discovery “rewrote decades of research on Earth’s most famous predator.”

Growth rings inside bones found in Montana’s Hell Creek Formation tell scientists that the new dinosaur was a fully grown T-rex half the size. Drawing on growth from other reptiles such as crocodiles, they also found that the major differences between the creature’s skull and an adult T-rex — changes in bone structure, nerve patterns and sinuses — are unlikely to be due to going through puberty alone.

The clues pointed to a dinosaur that is a distant T-Rex cousin known as Nanoterranus linensis, researchers reported in a study published Thursday in the journal. The nature.

Holly Woodward, a fossil bone expert at Oklahoma State University, said there is now “much more support and evidence” that this relative of T. rex could have existed. But he still doesn’t believe other mystery skeletons like Jane are anything new.

Other independent scientists also say the debate is far from over. Carthage College vertebrate paleontologist Thomas Kerr said the new skeleton is indeed an adult, but it may be a sister species of T. rex and not a distant relative.

There are similarities between the shape of the T. rex skull and the mystery patterns that prevent it from changing camps.

“I don’t think this study settles everything,” he said.

Study co-author James Napoli, with Studbrook University, said resolving this case of misidentification is critical to understanding how T. rex grew. Another big question is whether T. rex was the main predator towards the end of the age of dinosaurs 67 million years ago – or whether a smaller, but still powerful predator also roamed.

The new skeleton has been dubbed the “Dueling Dinosaur” because it was found attached to the bones of a Triceratops, and is currently on display at the North Carolina Museum of Natural Sciences.

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