In January 2024, researchers described a new species of Tyrannosaur known as Tyrannosaurus mcraeensis. T. mcraeensis is known to be a close relative of its later cousin Tyrannosaurus Rex, yet it is similar in size despite being as much as seven million years younger.

Despite T. rex being arguably the most popular and recognizable of all dinosaurs, it’s evolutionary history is poorly understood. The origin of it’s immediate family, or genus, has not been properly identified due to the lack of fossil material.

Tyrannosaur specimens have been described in both North America and Asia. There is an ongoing debate as to which one of these countries Tyrannosaurus comes comes from. T. mcraeensis suggests Tyrannosaurus originated in North America.