By Wachira Kigotho
East African Standard
The shores of Lake Turkana have offered another glimpse to early phases of human evolution.
Archaeologists have discovered a set of 1.5 million-year-old footprints at Ileret, an archaeological site at the northern shores of the lake. The footprints confirm the early man walked upright.
The discovery is reported in the current edition of Science, the journal that publishes significant original scientific research and policy issues.
The researchers from the National Museums of Kenya, Bournemouth University, George Washington University, Rutgers University and University of Cape Town say the findings add to the interpretation of the later pre-history of Africa.
According to Prof Matthew Bennet, the findings show that more than 1.5 million years ago, early man had evolved a modern human foot function and a style of bipedal locomotion that we would recognise today.
The new footprints are the second oldest in the world after the 3.7 million year-old prints in Laetoli in Tanzania. Prof Brian Richmond of George, a leading archaeologist from George Washington University, said discovery of early man’s footprints are incredibly rare event.
But for the first time, the researchers used a three dimensional method to analyse the ancient footprints and to compare them with those of modern humans.
The international team led by Prof Jack Harris of Rutgers University and Prof David Braun of University of Cape Town excavated two distinct sedimentary layers in a single outcrop at Ileret and revealed footprints that were preserved in fine-grained mud.
Footprint like human’s..
The surfaces have been dated precisely through inter-bedded volcanic ash layers to 1.51 to 1.53 million years old. Thereafter, the scientists created three-dimensional digital elevation models of the prints, which are accurate to a fraction of a millimetre.
According to Braun, the footprints were probably formed by Homo erectus, a species of hominids believed to have lived in the area during that period.
However, the major evidence is that the fossil footprints have a big toe that is in line with the other toes, a robust heel and anklebones, a pronounced longitudinal arch and short toes which are characteristics of a modern human foot.
"Through advanced scientific analysis, we were able to determine that the shapes of these prints are more like those formed by modern humans compared to the prints from Laetoli," said Bennet. Archaeologists believe the Tanzanian footprints were formed by Australopithecus afarensis, an older hominid species that lived in Eastern Africa between three to five million years ago.
But based on the size and the stride pattern of these newly discovered footprints, the team determined that the individuals responsible would have been about six feet in height.
Site at risk..
"The size and stature estimates derived from the Ileret prints compare well with those of our distant ancestor, Homo erectus, and are too large to have been formed by other hominid species that might have lived in this part of Africa," says Richmond.
According to the study, "Early Hominin Foot Morphology Based on 1.5-Million-Year-Old Footprints from Ileret, Kenya" the discovery supports archaeological hypothesis that Homo erectus had a larger home range that enhanced dietary quality and shift in cultural and biological adaptations in comparison to earlier hominids.
Unfortunately, the area in which the footprints are located is eroding, placing the valuable site at great risk. However, the process of laser scanning of the footprints is being used to preserve the discovery for posterity and further study.
"The digital scans are easily replicable and can be transformed into real-life casts available for museum display around the world or even in classrooms," says Ms Emma Mbua of the National Museums of Kenya.
The footprints are some of the recent discoveries made jointly by the National Museums of Kenya and international archaeological teams.
By Wachira Kigotho
East African Standard