The footprints of a hadrosaurs, a long extinct dinosaur with a bill resembling that of a modern duck, have been found preserved in Alaska. The footprints, evidence of which was published in a study by Perot Museum of Nature and Science, are thought to be more than 70 million years old and reside in Denali National Park. The study was published in the latest issue of scientific journal Geology.
The study was authored by Anthony R. Fiorillo, PhD, the Perot Museum’s curator of earth sciences, Stephen Hasiotis, PhD, of the University of Kansas’ Department of Geology and Yoshitsugu Kobayashi, PhD, of the Hokkaido University Museum. The site of the footprints was originally discovered in 2007 and has since been properly surveyed by a team of scientists and other experts.
Alaskan dinosaur footprint discovery
According to Anthony R. Fiorillo, one of the authors of the study, “Without question, Denali is one of the best dinosaur footprint localities in the world, but what we found that last day was incredible – so many tracks, so big, and so well preserved.” Fiorillo added “There were lots of invertebrate traces – the tracks of bugs, worms, larvae and more – which were important to us because they showed an ecosystem existed during the warm parts of the years.”
According to the study the footprints are from four distinct sizes of dinosaur, baby, juvenile, sub-adult and adult and ranged from a size of 5 inches right up to a colossal 24 inches in length. Stephen Hasiotis, another of the scientists who studied the site, said that “The Denali tracksite is extremely significant to the reconstruction of this Cretaceous high latitude polar ecosystem as it demonstrates higher annual temperatures compared to the present-day climate.”
The scientists posit that the discovery gives weight to a thesis detailing a much more active polar ecosystem in the distant past. Evidence from the preserved footprints suggests that all manner of animal life was present in the area, which is now in close to Tundra conditions for a good proportion of the year.
Giant dinosaur herds
The hadrosaurus, named after its bulky stature, is thought to have lived in large herds in Alaska. The animals were herbivores and survived by grazing on the plant life that existed in the area. Because of the small size of some of the footprints, about 13% of the tracks were from the baby range, it is thought that the dinosaurs lived in the area through winter. That implies a much greater range, and weight, of life in the area than exists today.
The hadrosaurs is often though of as the livestock of the dinosaur world. The beast, which lived in the Cretaceous period, lived in giant herds and may have formed part of the staple diet of many larger predators. The discovery of the animal’s footprints in the Alaskan National Park is an important one and, as Mr. Fiorillo says “one of the best dinosaur footprint localities in the world.”