Dinosaur-era bird tracks have finally believed to been discovered. The ancient animals each had three-toed footprints, but a few dinosaurs had a backward turned fourth toe that birds today use to grab onto a branch or give them drag while they land. So when paleontologist Anthony Martin noticed a four-toed impression pressed into an Australian rock that was probably over 100 million years old, he realized it was something distinct.
He stated he felt the track looked familiar but one he could not quite recognize. Then he realized who it belonged to, and where he had seen so many others like it. It was a bird track, extraordinarily similar to ones seen in sand off the coast of Georgia.
Within a few moments, Martin was positive he was staring at a bird footprint, close in size to one of today’s herons or egrets. Each of these birds has distinguishing four-toed footprints. His findings are now running in the present issue of Palaeontology magazine.
Not every one of the Cretaceous period birds had a backward turned fourth toe, but some theropod, which means to be bird-like, dinosaurs did. Their four slim toes would splay out to help them move, says Dr. Martin.
The Tyrannosaurus rex had a shrunken rear toe located near its Achilles tendon, but a raised toe would not show up in a track print. With birds having those kind of feet with the fourth toe, it was down to the ground, but the same digit on non-avian dinosaurs was most usually raised up.
The footprint he saw was in a piece of rock along with two other tracks. They each were along the same size, but just two out of the three had the backwards toe. This led Martin and his associates to determine that most likely it was a bird-sized dinosaur and two birds which had created all the various tracks. Sand dries extremely fast so the prints had to have been made within a very short period of time, maybe within the same 24 hours. The birds and the dinosaur must have shared an ecosystem, the same as modern animals would.
When the footprints were first created, around 105 million years ago, Australia had been a lot farther south than the location it is now. An area named Dinosaur Cove, which is now close to the southeastern edge of Australia, would have then been in a region that experienced temperatures similar to what is at the South Pole. Non-avian dinosaurs and birds would still have been in the process of splitting apart on their evolutionary passage.
Numerous researchers consider birds as theropods, and they are looking for the clues how contemporary birds deviated from their massive cousins, and how feathered flight began.
These tracks give important information toward answering some of the scientists’ questions. Although sometimes Martin wonders if finding tracks raises more questions than it answers.
Could scientists be wrong and none of these tracks be from any type of bird, yet instead from a theropod dinosaur? This is possible but not likely at this time. Might have the Cretaceous birds in polar Australia have been more ungainly than birds today, henceforth the slipping tracks being observable? No one knows for sure, but with these bird tracks being discovered and believed being dated back to the dinosaur-era, it is bringing the answers closer.
Written by: Kimberly Ruble