Students from the Koobi Fora Field School excavated the footprints between 2006 and 2008. Along with the prints of many animals, they found three sets of human-like footprints. One was probably a child’s tracks.
The prints were made in fine sand on what was once a riverbank. The sand had been sandwiched between layers of volcanic ash. Scientists estimate the height of the adults to be about 5ft 9in from the stride length.
David Braun, an archaeologist from the University of Cape Town in South Africa, told Reuters:
“It was kind of creepy excavating these things to see all of a sudden something that looks so dramatically like something that you yourself could have made 20 minutes earlier in some kind of wet sediment just next to the site.
“These could quite easily have been made on the beach today.
An international team, led by Professor Matthew Bennett from Bournemouth University in England, has studied the footprints. They published their conclusions in Science last week.Professor Bennett says:
“Our findings from Ileret show that by 1.5 million years ago, these individuals had evolved an essentially modern human foot function and a style of two-footed locomotion that we would recognize today.
“Foot bones are rarely preserved because they are small, encased in flesh, and easily consumed by carnivores.
“Consequently, our knowledge of foot anatomy and function in our early ancestors is poor. Fossil footprints are rare but when they are found, they provide an invaluable line of evidence.
By finding the age of the surrounding ash layers, scientists were able to estimate the age of the footprints to about 1.51 million to 1.53 million years old. They conclude that the prints were likely to have been made by the early hominid Homo ergaster or early Homo erectus. Homo sapiens or modern man first appeared 200,000 years ago.
John Harris, a paleoanthropologist at Rutgers University in New Jersey, USA is one or of the co-authors of the Science paper. He told the National Geographic:
The ancient footprints indicate a rounded heel, pronounced arch and a big toe parallel to the other toes just as modern humans have. The big toes of chimpanzees, by contrast, splay outward, which is useful for grasping branches.
“We’ve lost that, but what we’ve created is a platform from which we can step up on and balance ourselves on and push off on in bipedal locomotion.
Image courtesy of Matthew Bennett/Bournemouth University