Footprints of a baby Apatosaurus, roughly the size of a pug dog, were spotted in the foothills near Denver.
A baby dinosaur approximately the size of a pug dog scurried alongside what may have been its mom or dad some 148 million years ago in what is now foothills near Denver, scientists reported today (Nov. 1) at the annual meeting of the Geological Society of America in Denver.
They caught the paleo-action in the footprints left behind there near the town of Morrison, Colo. The scientists think the dinosaur prints, a set of infant prints next to partial prints from an adult, belonged to Apatosaurus, a sauropod — giant, long-necked dinosaurs that preferred veggies — and once known as Brontosaurus.
As an adult, Apatosaurus is the largest dinosaur found in the Denver metro area, the researchers say, spanning a length of three school buses and weighing as much as eight Asian elephants.
The prints likely made by the infant Apatosaurus were tiny — if you were to place a mug over one, it would completely eclipse the print, according to one of the discoverers, Matthew Mossbrucker, director of the Morrison Natural History Museum in Boulder, Colo.
"The distance between each step is two times wider than what we observe in walking tracks, indicating the animal was at a low-speed run," Mossbrucker said. "I am not aware of any running sauropod tracks anywhere."