Oldest hominid footprints found: they date back 6 million years

They are the oldest evidence of our ancestors' bipedalism. Now the new dating has arrived. They had been found, fossilized, on a beach in Crete near Trachilos in 2017

Found in 2017 near Trachilos, on a beach in Crete, the fossilized footprints are the oldest direct evidence we have of bipedalism in our ancestors. Even older than previously reported, they beat even their African counterparts. When they had been discovered about four years ago, they had been claimed to be evidence of human ancestors walking upright 5.7 million years ago. This had come as something of a shock, as it raised the possibility that one of the most important steps in human evolution had taken place outside of Africa. Now comes a new dating that takes it back even further, to about 6 million years ago.

Fingerprints going back 6 million years

A paper published in Scientific Reports, highlights that the footprints were made earlier than previously thought. Using the magnetic polarity of the layer in which the footprints were found and the abundance of accompanying marine organism species, the paper estimates that the tracks are found in sediments deposited 6.05 million years ago. Only when the material was fresh would it have been soft enough to hold the footprints so clearly.

And, according to the authors, there's even a small chance that the footprints are even older. "The tracks are almost 2.5 million years older than the tracks attributed to Australopithecus afarensis (Lucy) from Laetoli in Tanzania," Dr. Uwe Kirscher of the University of Tübingen said in a note. This does not necessarily mean that hominids walked upright in Europe before their hominins in Africa.

Hominid bipedalism

For example, the species Orrorin tugenesis lived in Kenya at about the same time. Although neither their footprints nor foot bones have been found, the shape of Orrorin's femurs suggests that they probably walked upright. The temporary expansion of the Sahara at the time likely prevented interchange between Europe and most of Africa, in which case the upright gait may have evolved independently in both places.

However, if Kirscher and his co-authors are correct, the work indicates that we need to expand the range within which we look for the origins of human bipedality and could explain how our ancestors made the transition to the upright position. "The earliest human foot used to walk upright had a ball, with a strong parallel big toe and successively shorter lateral toes," said co-author Professor Per Ahlberg of Uppsala University.

Findings of our ancestors' remains continue to reveal valuable information about our evolutionary history. A secret cave was recently discovered among the last hiding places of Neanderthals in Gibraltar, while a study of archaic blood has unraveled the mystery that led the species to extinction. Other fossils that rewrite our evolutionary path are the Dragon Man's skull in China and artifacts found in Israel.

Stefania Bernardini