T. Rex’s Asian ancestry reveals in immigration research

A comprehensive new study published on the Royal Society Open Science on May 7, 2025 solves the long-standing paleontological mystery about the origins of one of the most iconic predators in history. The researchers found that while Tyrannosaurus rex evolved in North America, its direct ancestors likely spanned 70 million years ago from Asia, a discovery reshapes our understanding of dinosaur evolution and the connection between ancient continents.

Tracking the king’s family tree

For decades, scientists have debated whether T. Rex comes from North American ancestors or Asian relatives. An international research team led by researchers at University College London has employed sophisticated biogeographic analysis to track the evolutionary history of these terrifying predators.

“The geographical origins of T. Rex are the subject of intense debate. Paleontologists are on whether their ancestors are from Asia or North America,” said Cassius Morrison, a doctoral student at UCL Earth Sciences.

Their findings suggest that T. Rex’s “grandparents” may have moved from Asia to North America through the Bering Land Bridge, the same route that later the human population reached the Americas. This confirms the earlier hypothesis that Rex (T.

Climate links to dinosaur giants

The study reveals another fascinating pattern: the evolution of the giant body size of Tyrannosaurus Rex and its cousin, the mysterious large beetle, cooled globally after the highest heat in the Cretaceous period approximately 92 million years ago. This suggests that these dinosaurs may be adaptable to help them thrive in cooler environments, including feathers or warmer blood metabolism.

The main findings of the study include:

• T. Rex
• Large dinosaurs are more widely distributed than previously thought
• After global cooling
• The extinction of other giant predators (Choodosaurids) developed a larger-sized ecological opportunity for these groups about 90 million years ago

Mysterious large coat

Although T. Rex both dominates scientific research and predominates popular culture, the study also sheds light on the mysterious Megaraptors – equally fascinating predators who have evolved another hunting strategy with long arms and a large number of claws, rather than harsh claws.

“About 120 million years ago, at the beginning of their evolutionary history, the Megaputs were Dr. Mauro Aranciaga Rolando of Bernardino Rivadavia’s Natural Sciences.

The team concluded that large giants could be found throughout most of the ancient mega-sized Gondwana, including areas where fossils have not been found, such as Europe and Africa. This shows that these powerful predators are more diverse and broader than previously recognized.

Hunting different preys in different places

An interesting aspect of this study is how these two related predators develop different hunting strategies based on the prey available in their environment. In North America, T. Meanwhile, on the southern continent, Megaraptors may specialize in hunting juvenile sauropods (slavery of juveniles), the long-necked giants that dominate these ecosystems.

This geographical and ecological separation helps to drive the evolution of its unique features: the Tyrannosaurus rex has a spur jaw bone, while the long and long arms have huge claws.

“Our discovery has shed light on the emergence of the largest Tyrannosaurus rexes in North and South America during the Cretaceous period and how and why they grew so big at the end of the dinosaur era,” said Charlie Scherer, a graduate student in geosciences and founder of UCL PALAETONETOLOCY SOCICEL.

This study challenged previous findings, showing that T. Rex has evolved completely within North America, and believes that the recent discovery of fossils of alleged T. Rex relatives in New Mexico (Tyrannosaurus mcraeensis) is not reliable. Instead, evidence suggests that Asian ancestors migrated to North America and brought about Rex’s lineage.

As researchers continue to unearth new fossils and adopt advanced analytical techniques, our understanding of dinosaur evolution continues to evolve – revealing a complex story of a complex continental movement, climate change and ecological opportunities that influence the incredible diversity of prehistoric life.