Fossil footprints tell story of prehistoric parent's journey

Evidence of that type of frightening trek was recently uncovered, and at nearly a mile it is the longest known trackway of early-human footprints ever found.

The discovery shows the archaeological findings of footprint tracks at White Sands National Park in New Mexico. The tracks run for 1.5 kilometers (.93 miles) and show a single set of footprints that are joined, at point, by the footprints of a toddler. The paper's authors have shown how the footprint tracks, as well as the distinctive shapes they left, show a woman (or possibly an adolescent male) carrying a toddler in their arms, shifting the toddler from left to right, and occasionally putting the child down.

"When I first saw the intermittent toddler footprints, a familiar scene came to mind," said Thomas Urban, research scientist at Cornell University. Urban has pioneered the application of geophysical imaging to detect footprints.

The tracks were found in a dried-up lakebed, which contains a range of other footprints dating from 11,550 to 13,000 years ago. The lakebed's formerly muddy surface preserved footprints for thousands of years as it dried up.

Previously found in the terrain are the prints of animals such as mammoths, giant sloths, saber-toothed cats and dire wolves. Sloths and mammoths were found to have intersected the human tracks after they were made, showing that this terrain hosted both humans and large animals at the same time, making the journey taken by this individual and child a dangerous one.

The recently discovered footprints were noted for the straightness, as well as being repeated a few hours later on a return journey -- only this time without a child in tow, which can be seen from the tracks.

"This research is important in helping us understand our human ancestors, how they lived, their similarities and differences," said co-author Sally Reynold, senior lecturer in hominin paleoecology at Bournemouth University. "We can put ourselves in the shoes, or footprints, of this person (and) imagine what it was like to carry a child from arm to arm as we walk across tough terrain surrounded by potentially dangerous animals."