Fossil footprints: The fascinating story behind the longest known prehistoric journey
Every parent knows this feeling: Your child is crying and wants to go home, you hold him to relax and accelerate, your arms are tired from the long road ahead – but you shouldn’t stop. Add to that the muddy ground and the various hungry hunters around you.
This is the story that tells us the longest path of fossil footprints in the world. This discovery, published in Quaternary Science Reviews, is from New Mexico, USA; It comes from White Sands National Park and was carried out by an international team collaborating with National Park Service staff.
These footprints were found in a dried-up lake bed called Playa. This Playa dates from the end of the last ice age (11,550 years ago) to about 13,000,000 years ago and contains hundreds of thousands of footprints. Unlike many other known footprint paths, this road; is remarkable with its length – at least more than 1.5 km – and its flatness. Whoever owns these footprints did not deviate from their path. But even more remarkable than that is that it follows its paths again after a few hours.
Each fragment found tells us a story: a skid trail somewhere, a run away to avoid a puddle… The ground was wet, muddy, and slippery; they were walking fast, which may have been tiring. We estimate that they are walking over 1.7 meters per second. A comfortable walking speed is about 1.2 to 1.5 meters per second on a flat, dry surface. The scars are quite small, most likely made by a woman or a man of adolescence.
On this distant journey, the person carrying the child may have put the child down, perhaps while pausing to carry the child more comfortably or to have some rest; because traces of children were also found on the ground. Judging by the size of these marks, the marks were made by a two-year-old or a little younger child who was just beginning to walk. The child was moved on this trip, but not on the way back.
We can see traces as evidence of this transport. The scars are wider, more diverse in morphology, and usually, a characteristic banana shape due to the load carried, and this is due to the outward rotation of the foot. The traces of the journey home are less diverse and narrower in shape. We could even go so far as to suggest that the surface dried a little between two journeys.
Playa was home to many extinct ice age animals. Perhaps these were hunted to extinction by humans, perhaps not. The tracks of these animals helped determine the age of the trail.
We found traces of mammoths, giant sloths, saber-toothed cats, scary wolves, bison, and camels. We have produced footprints to provide evidence of how these animals could have been hunted in the past. Moreover, the research to be published includes children playing in puddles formed on giant sloth tracks and jumping between mammoth tracks; it even talks about hunting and butchery.
Between the outbound and return journey, a sloth and a mammoth crossed the way out. The footprints of the return journey also pass near these animal tracks. Lazy tracks indicate awareness of human transitions. As the animal approaches the path, it appears to rise on its hind legs to catch the scent. Before landing on all fours and escaping, he pauses, trampling over human tracks. He was aware of the danger.
In contrast, mammoth tracks in a field made by a large bull most likely pass this path, where people are walking without deviations, most likely without realizing it. This path tells us an extraordinary story. What was this individual doing alone, on the beach, in a hurry with a child?
This is a sign of a social organization, they knew where to go, they made sure they would receive a friendly welcome. Well, was the boy sick? Or was he being returned to his mother? Or was there a rainstorm that caught a mother and child off guard? There is no way we can know for sure. With so little evidence, it’s still easy to speculate.
What we can say is that the woman is probably uncomfortable with this hostile scene, yet she is ready to go on the journey. Remember that even prehistoric parents experienced these feelings when you ran around the supermarket with a tired child in your arms.