Research may solve mystery of whether fossil is young T. rex or new species

The skull of a tyrannosaur that may be a new species (North Carolina Museum of Natural Sciences via AP)

Scientists have long puzzled over the origins of a mysterious dinosaur excavated in the 1940s: was it a young Tyrannosaurus rex or another type of dinosaur?

At first, researchers had only a tyrannosaur skull to go by, making it hard to tell if it belonged to a child or adult. Another skull and skeleton nicknamed Jane added to the debate, but did not settle the controversy.