Washington: Paleontologists have once again discovered infant dinosaur footprints in the foothills west of Denver, near the town of Morrison.
The discovery was made by Morrison Natural History Museum staff.
Dating from the Late Jurassic, some 148 million years ago, these tracks were made before the Rocky Mountains rose, when Morrison was a broad savanna full of dinosaurs.
The fossil tracks represent infant sauropods, according to discoverer Matthew Mossbrucker, the museum``s director.
Sauropods are giant, herbivorous long-necked dinosaurs, sometimes known as "brontosaurs." The sauropod Apatosaurus was first discovered in Morrison in 1877. As long as three school buses parked end to end, and weighing as much as eight Asian elephants combined, Apatosaurus is the largest dinosaur found in the Denver metro area.
Leading paleontologist Dr. Robert T. Bakker of the Houston Museum of Natural Sciences (who also serves as the Morrison Museum``s volunteer curator of paleontology) remarks, "The latest discovery by the Morrison Natural History Museum is a tribute to Director Matt Mossbrucker and his crew of sharp-eyed volunteers. Never before has science given us such an intimate glimpse of baby brontosaurs - a window into Jurassic Family Values."
"Three years ago the Morrison Museum crew detected adult and baby Stegosaurus, hinting that the area had been near a stego nesting ground. The new baby sauropod tracks may well be the very smallest, youngest apatosaurs ever discovered, in the form of bone or trackways. Was Morrison an apatosaur nursery? The evidence is fascinating," muses Bakker.
The tracks are ovular and can be nearly eclipsed by a coffee mug, suggesting that the infant sauropods were about the size of a small dog. While one animal left average walking footprints, another infant dinosaur ran parallel to adult tracks.
The running trackway is unusual. "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," remarks Mossbrucker.
"I am not aware of any running sauropod tracks anywhere." Nor is Bakker.
Information regarding the new tracks was presented at the 2010 Geologic Society of America Annual Meeting & Exposition in Denver.