Footprints found in Australia are 100 million years old Live Science reported Monday.
"These tracks are evidence that we had sizeable, flying birds living alongside other kinds of dinosaurs on these polar, river floodplains, about 105 million years ago," Anthony Martin, a paleontologist from Emory University in Atlanta told Live Science. "In some dinosaur lineages, that rear toe got longer instead of shorter and made a great adaptation for perching up in trees. Tracks and other trace fossils offer clues to how non-avian dinosaurs and birds evolved and started occupying different ecological niches."
Scientists found the two webbed feet footprints, and one right beside it which resembled a non-avian threopod, on the cliffs of the country's Dinosaur Cove, located on the coast of southern Victoria. The third print may be a coelurosaur or the category of dinosaurs similar to the bird species that include dinosaurs such as the Tyrannosaurus Rex.
The prints were found in a sandstone area measuring approximately 650 square centimeters in length. One had a toe that went backwards, which a characteristic that is not unusual today.
Researchers feel the prints were imprinted when the Cove's riverbank was immersed in wet sand after its floodwaters dissipated in the spring or summer Live Science reported. It is not known if the prints are from species who lived in the area during the winter season, or traveled there when the temperatures warmed up
Researchers believe they are those of prehistoric bird species, particularly a bigger egre bird, or smaller heron who were alive in the early cretaceous period Live Science reported.
"The teeth are weird and there are some stomach contents, which is unusual," said paleontologist Gareth Dyke, of the University of South Hampton in the United Kingdom told Live Science in January. It's more evidence for the uniqueness and range of ecological specialization that are seen in these particular Mesozoic birds."
