A set of fossilized footprints discovered on the Greek island of Crete has been dated to around 6.05 million years ago, making them the oldest known direct evidence of a human-like foot used for upright walking.
The footprints were found near the village of Trachilos in western Crete and were first described in 2017. An international team led by researchers from the University of Tübingen later applied geophysical and micropaleontological techniques to establish a more precise age for the site.
For scientists studying human evolution, footprints are especially valuable. Unlike bones, which can be scattered or incomplete, tracks capture a direct record of movement. In this case, they preserve evidence from a period more than six million years ago, when fossils linked to early human ancestors remain relatively rare.
Older Than One of Humanity’s Most Famous Trackways
The new analysis dates the Trachilos footprints to approximately 6.05 million years ago. The study, published in Scientific Reports, identifies them as the oldest direct evidence of a human-like foot discovered so far.
Lead author Uwe Kirscher noted that the tracks are nearly 2.5 million years older than the famous Laetoli footprints in Tanzania, which are attributed to Australopithecus afarensis, the species that includes Lucy.
Their age also overlaps with that of Orrorin tugenensis, an early pre-human species that lived in Kenya between 6.1 and 5.8 million years ago. Fossils associated with Orrorin include femurs that suggest upright walking. Researchers point out, though, that no foot bones or footprints linked to the species have ever been found.
That detail makes the Trachilos discovery particularly noteworthy, as it provides direct evidence of foot anatomy from a very early stage of human evolution.
Reading the Ancient Tracks
The tracks preserve several characteristics associated with bipedal locomotion. Per Ahlberg, a professor at Uppsala University and co-author of the study, said the foot had a ball, a strong big toe aligned with the others, and progressively shorter side toes.
“The oldest human foot used for upright walking had a ball, with a strong parallel big toe, and successively shorter side toes,” Ahlberg explained.
The researchers also identified differences compared with later hominins. Their analysis stated the foot had a shorter sole than that of Australopithecus. The arch was not strongly developed, while the heel appears to have been narrower.
These conclusions come from footprints preserved in beach sediments that later fossilized. Unlike skeletal remains, they record how a foot actually interacted with the ground, offering another perspective on anatomy and movement.
Ancient Clues Point to a Changing Landscape
The study also examines the environmental setting in which the footprints were made. Six million years ago, Crete was connected to mainland Greece through the Peloponnese, allowing land animals to move across the region. Madelaine Böhme, another co-author of the research, said that:
“We cannot rule out a connection between the producer of the tracks and the possible pre-human Graecopithecus freybergi.”
Those remains come from depositsdated to roughly 7.2 million years ago, around 250 kilometers from the Trachilos site. Geochemical evidence gathered by the team indicates that dust from North Africa reached Crete during that period. The researchers dated mineral grains found in the sediments and obtained ages between 500 and 900 million years. They describe these values as typical of North African desert dust transported by wind.
The paper also supports earlier work by Böhme and her colleagues on what they call the “desert swing” hypothesis. In this model, short-lived phases of desert expansion in Mesopotamia and the Sahara influenced the movement of mammals between Eurasia and Africa. The authors suggest that these environmental changes may have affected the geographic distribution of some of the earliest pre-human populations.
