An artist's impression of what the treacherous journey might have looked like.
Ancient human footprints found in a parched New Mexico lakefront show a remarkably detailed snapshot from more than 10,000 years ago. A teenage or small adult woman carries a young child for nearly a mile through muddy terrain frequented by mammoths, giant sloths, saber-toothed cats, and terrible wolves. Then the traveler turns around and makes the return trip without the child in tow, perhaps the toddler has brought it to its destination.
The prints, believed to be the longest known trace of early human footprints, tell a dramatic tale of danger and endurance. A new study in the online edition of Quaternary Science Reviews describes how the traces were discovered and studied in White Sands National Park and what they contribute to the ichnological (trace fossil) record – and shows us our ancestors from the Ice Age.
"This research is important in understanding our human ancestors, their lives, their similarities and differences," said Sally Reynolds, lecturer in hominin paleoecology at Bournemouth University, UK and co-author of the study of the archaeological find. "We can put ourselves in that person's shoes or in their footprints (and imagine) what it was like to carry a child from arm to arm as we walk through difficult terrain surrounded by potentially dangerous animals."
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An international team working with National Park Service staff found the footprints in a lakefront that contains other footprints dating back between 11,550 and 13,000 years ago. When the lakeshore dried up, it kept footprints for thousands of years.
Minor prints that appear in spots on the banks of the ancient Otero Lake indicate that the caregiver will occasionally lay down the child who is believed to be 3 years or younger. The prints show that the person carrying the child made a return trip on the same route a few hours later, although the shape of the prints suggests that the child was no longer there. Taken together, the prints tell the story of a grueling journey, but each track offers even more specific details: the walking pace, a slip here, a route there to avoid a puddle.
"The ground was wet and muddy and they were walking at a pace that would have been strenuous," wrote Reynolds and colleague Matthew Robert Bennett of Bournemouth in a play about the discovery in The Conversation.
Left: footprints in both directions. Middle: Occasionally a child's prints appear. Right: A petrified cast of the person, most likely a woman, who carried the child through the muddy terrain of what is now New Mexico.
National Park Service
White Sands National Park contains a treasure trove of fossilized human and animal footprints. Last year, a team led by Cornell University published a study onto study the movements of mammoths, humans and giant sloths there 12,000 years ago. A mammoth trail showed a human footprint that was later left in the same spot and gave a rare glimpse into the interaction between humans and megafauna so many years ago.
"We never thought we'd look under footprints," said Cornell's Thomas Urban, who contributed to both the 2018 study and the new study. "But it turns out that the sediment itself has a memory that beautifully records the effects of the animal's weight and momentum. It gives us an opportunity to understand the biomechanics of extinct fauna that we have never had before . "