1. New Species of Tyrannosaurus
The partial skull of a dinosaur found 40 years ago has been identified as a new species of Tyrannosaurus, closely related to Tyrannosaurus rex. The research adds a new twist to the debate about how many species of tyrannosaurs there were and could help to clarify the evolution of the iconic predator.
2. Origins of T. rex
T. rex appeared in North America around 68 million years ago, 2 million years before the mass extinction that wiped out most dinosaurs. Palaeontologists have debated the carnivore’s origins, with some suggesting prehistoric Asia and others placing its origins in southern North America.
3. Tyrannosaurus mcraeensis
The fossil re-examined by Anthony Fiorillo and his colleagues was found in rock layers known as the McRae Group in western New Mexico. They propose that the specimen represents an older species, which they named Tyrannosaurus mcraeensis in reference to the rocks in which it was found.
4. Physical Differences
Tyrannosaurus mcraeensis lived about 4 million years earlier than T. rex and was comparable in size. However, it had subtle differences, including less developed ridges on its brows and a more slender skull.
5. Debate over Species Assignment
Other recent studies have proposed multiple species of Tyrannosaurus, fueling debate among dinosaur paleontologists. Some argue that many of the anatomical features that supposedly make the new species unique can also be found in T. rex specimens.
6. Evolution of Tyrannosaurus
The existence of the large tyrannosaur millions of years before T. rex suggests that south-western North America was an important center for the dinosaur’s evolution. The proposed age dates for the specimen warrant further study to outline a clearer picture of dinosaur evolution in the Cretaceous Period.
7. Prey of T. rex Lineage
The New Mexico tyrannosaur was found in the same rocks as giant horned dinosaurs, duckbilled dinosaurs, and long-necked herbivores. The researchers suggest that the lineage leading to T. rex might have evolved their giant size to prey on these large herbivores.
In conclusion, the discovery of Tyrannosaurus mcraeensis provides insight into the evolution and origins of T. rex. The proposed species assignment and the findings of the study will continue to fuel debate among paleontologists and further studies are warranted to clarify the picture of dinosaur evolution in the last few million years of the Cretaceous Period.
A new species of Tyrannosaurus has been identified from a fossil dating back to 80 million years ago, making it one of the oldest and most primitive members of the tyrannosaur family. The fossil, named ‘Moros intrepidus’, was discovered in Utah and is estimated to have been around 30 feet long and weighed around 1,000 pounds. The findings suggest that the Tyrannosaurus lineage evolved earlier and adapted to a wider range of ecological niches than previously thought. This discovery sheds new light on the early evolution of these iconic predators and provides valuable insights into the diversity of the tyrannosaur family during the Late Cretaceous period.