Infant dinosaur footprints have been discovered in the foothills west of Denver, Colorado, near the town of Morrison. These tracks were made about 148 million years ago, before the Rocky Mountains rose, when the savanna was full of dinosaurs.
According to Matthew Mossbrucker, director of the Morrison Natural History Museum, who discovered the prints, the fossil tracks represent infant sauropods. Sauropods were giant, herbivorous long-necked dinosaurs, sometimes known as "brontosaurs." The sauropod Apatosaurus was first discovered in Morrison in 1877.
Details of the findings were presented at the 2010 Geologic Society of America Annual Meeting & Exposition in Denver on November 1. Although collected five years ago, these tracks were a part of a backlog of new discoveries made by Museum staff. The tracks are on permanent display at the Morrison Natural History Museum.
Paleontologist Dr Robert T Bakker of the Houston Museum of Natural Sciences (who also serves as the Morrison Museum's volunteer curator of paleontology) said on the finding, "The latest discovery 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."
The tracks are ovular in shape and can be covered by a coffee mug. This would mean 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 scientists also found an unusual pattern. "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," said Mossbrucker. "I am not aware of any running sauropod tracks anywhere."
