New Study Suggests Fossils Thought to be Young T. Rex are Actually Adults of a Different Species
A recent analysis of fossils previously thought to be juvenile T. rex has now shown that they are actually adults of a small tyrannosaur species called Nanotyrannus lancensis, with distinct differences from the T. rex. The study, conducted by Dr. Nick Longrich from the Milner Centre for Evolution at the University of Bath, and Dr. Evan Saitta from the University of Chicago, has brought into question previous interpretations of these fossils.
The fossils of Nanotyrannus were originally discovered in Montana in 1942, and for decades, paleontologists have debated whether they belong to a separate species or if they were simply young T. rex. However, the recent analysis of the fossils has provided evidence that these animals were nearly full-size adults and not fast-growing juveniles, as would be expected of young T. rex.
Using a variety of methods including measuring growth rings in the bones, and modeling growth patterns, the researchers have confidently identified the fossils as belonging to a species distinct from T. rex. The findings suggest that Nanotyrannus is not closely related to Tyrannosaurus and may even sit outside the family Tyrannosauridae, which T. rex is part of, in its own family of predatory dinosaurs.
The study also revealed the existence of a previously overlooked fossil of a young T. rex, which was identified as such based on unique skull features that distinguish it from Nanotyrannus.
The findings have sparked controversy in the field of paleontology, with Dr. Longrich stating, “It’s amazing to think how much we still don’t know about the most famous of all the dinosaurs. It makes you wonder what else we’ve gotten wrong.”
The researchers have published their findings in the journal Fossil Studies, and their study raises questions about the diversity of dinosaurs and the potential underestimation of different fossil species.
The full study, “Taxonomic status of Nanotyrannus lancensis (Dinosauria:Tyrannosauroidea)—a distinct taxon of small-bodied tyrannosaur,” can be found in Fossil Studies, DOI: 10.3390/fossils1010009. This latest study adds to the ongoing dialogue in paleontology about the classification and identification of dinosaur species.