CHICAGO (WBBM) — The University of Chicago’s head dinosaur hunter has unwrapped a small new package with teeth and claws–a distant ancestor of T-Rex.

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Eodromaeus, or dawn runner, was the pint-sized predecessor to the carnivorous dinosaurs. It stood about four feet tall, weighed about 15 pounds. It was very agile, had a tail and possessed dog-like teeth. It roamed the earth about 230 million years ago.

“It give us a bird’s eye view of where the predatory line of dinosaurs came from,” said the University of Chicago’s Paul Sereno. “This is really the oldest and most primitive form of a lineage that ultimately would give rise to animals as fearsome as T-Rex.”

The new dino was found in Argentina–in the oldest dinosaur bed on the planet–in 1996 but took years to dig and clean the skeleton. Then scientists had to figure out their importance.