Was Tyrannosaurus an Invasive Species?

Tyrannosaurus rex, king of the dinosaur age, wasn't a North American native as many experts had previously thought, a new study suggests.

Instead, the giant tyrannosaur was likely an invasive species from Asia that dispersed into western North America once the opportunity presented itself, paleontologists said.

"It's possible that T. rex was an immigrant species from Asia," said study co-researcher Steve Brusatte, a paleontologist at the University of Edinburgh in Scotland. But he cautioned that the finding isn't necessarily a "slam dunk," and that more research is needed to say for sure.

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