New York, Nov 13: Mysterious invisible footprints hiding since the end of the last ice-age have been discovered using a special type of radar by Cornell University researchers.
According to the study published in the journal 'Scientific Reports', the fossilised footprints also reveal what lies beneath this footprints and a bunch of information about how humans and animals moved and interacted with each other 12,000 years ago.
The lead author of this study Thomas Urban from Cornell University said, "We never thought to look under footprints, but it turns out that the sediment itself has a memory that records the effects of the animal's weight and momentum in a beautiful way."
Thomas also added, "It gives us a way to understand the biomechanics of extinct fauna that we never had before."
The researchers have examined the footprints of humans, mammoths and giant sloths in the White Sands National Monument in New Mexico.
The researchers were able to resolve 96 per cent of the human tracks in the area under investigation using ground-penetrating radar (GPR), as well as all of the larger vertebrate tracks.
How this examination works?
Basically, GPR is a nondestructive method that allows researchers to access hidden information without the need for excavation.
The sensor, a kind of antenna. This antenna is dragged over the surface, sending a radio wave into the ground. The signal that bounces back gives the image of what's under the surface.
Regarding this research Thomas said, "...there are bigger implications than just this case study."
"The technique could possibly be applied to many other fossilised footprint sites around the world, potentially including those of dinosaurs. We have already successfully tested the method more broadly at multiple locations within White Sands," said Thomas.
Thomas's Co-author Sturt Manning said, "While these 'ghost' footprints can become invisible for a short time after rain and when conditions are just right, now, using geophysics methods, they can be recorded, traced and investigated in 3D to reveal Pleistocene animal and human interactions, history and mechanics in genuinely exciting new ways."