Washington, June 25 : A new study has suggested that between 145 and 100 million years ago, a dinosaur ran nearly 11 miles per hour in a straight line next to a lake in Korea.
According to a report in Discovery News, after studying dino footprints, paleontologists determined that the tracks were made by a small dromaeosaurid, which was a carnivorous Velociraptor-like dinosaur.
In Greek, the word dromaeosaurid fittingly means "running lizard."
The tracks are quite rare, as they represent the first didactyl, or two-toed, raptor footprints from Korea. Such footprints are only known from two other sites in the world, both in China.
The running dromaeosaurid might have been trying to escape an even larger carnivorous dino, but the researchers can't be certain.
"It was a fast animal, but we do not know if it was influenced by other animals in its behavior," co-author Martin Lockley told Discovery News.
Lockley, a professor of geology and curator of the University of Colorado at Denver Fossil Footprint Collection, and his colleagues found the dinosaur's footprints while working at the Haman Formation on Chu Island in Korea.
The footprints they found consist of two toes per print. Each digit has four attached, concentric pads terminated by a very prominent and sharp raptorial claw.
"This strongly curved and sharp claw was held off the ground surface in normal locomotory situations in order to prevent the ungual from becoming dull with repeated contact against an abrasive substrate, strongly suggesting that it had an offensive function, such as attacking prey," Lockley and his colleagues wrote in a paper summarizing their finds.
Aside from revealing that the dinosaur was in too big of a hurry to kick with its destructive claws, the footprints indicate the animal's hip height, which the researchers calculated as being about 27.5 inches.
According to Lockley, prior research determined that hip height is about five times the footprint length. Speed can then be calculated from hip height and stride length.
Peter Makovicky, assistant curator of Fossil Amphibians and Reptiles at The Field Museum in Chicago, explained that the tracks are important, because they fill in gaps within the fossil record.
The size, speed and location data will now be added to other didactyl findings, which suggest the meat-eating dinosaurs moved in flocks or herds, although the Korean individual probably ran without a group in that one preserved moment.
According to Makovicky, this particular dinosaur was about the size of an emu, and might have behaved in a similar manner.
"Like emus, the feathered raptor dinosaur would have been too big to fly, but it certainly could run fast," he added.