T. Rex Footprints Are a Discovery

A T. rex apparently went for a stroll through what is now North Dakota, and scientists just traced its steps. Researchers report finding the first known series of footprints from an adult Tyrannosaurus rex: a 23-foot-long trackway of four three-toed prints discovered in the Hell Creek Formation and dated to about 66.5 million years ago, the Guardian reports. Until now, only two adult T. rex footprints had been confirmed—in New Mexico and Montana—and neither showed how the animal was moving, per CBS News.

Each print measures roughly 3 feet long, with a stride of about 13 feet—suggesting the animal was moving at a pace similar to a fast human walk, around 3.5mph to 4.5mph. Scientists used high-resolution 3D scans to document and re-create the tracks, per the Guardian, which they say capture a rare "moment of behavior." Three of the prints will be airlifted to the Denver Museum of Nature and Science later this year.