Ellen Bartlett
More than 100 000 years ago, probably on a rainy day, a human walked in wet sand near what is now Langebaan Lagoon. The footprints he, or more likely she, left behind were covered in more sand, in succeeding layers blown in on the sea winds, and then preserved as the dunes slowly turned to rock.
The fossilised prints, found by geologist Dave Roberts of the Council for Geoscience, are among the earliest traces of anatomically modern humans ever uncovered.
Subjected to a series of tests by the Quaternary Dating Research Unit at the Council for Scientific and Industrial Research (CSIR), the fossils’ age is estimated at 117 000 years.
Roberts and Lee Berger, a palaeoanthropologist at the University of the Witwatersrand, announced the discovery this week in Washington DC. The two also describe the footprints in the September issues of the South African Journal of Science and National Geographic.
The prints head down the steep slope of a sand dune, on a diagonal. There are two complete prints, plus the eroded remains of a third, in a right-left-right march toward the beach. The feet that made the prints were small, about 22cm long. While foot length is not a precise predictor of height, Berger said in a recent interview, the feet probably belonged to “a smallish individual,” someone of a stature comparable to adult San men and women in the central Kalahari before 1915.
The image is an evocative one, the prints a haunting hello from our earliest direct ancestors. “As my toes touch the rock, I feel an almost electric connection to the past,” wrote Rick Gore, National Geographic senior assistant editor, after removing his shoes and socks and fitting his foot into one of the prints.
By themselves the prints do not add much to what is already known about early humans – they cannot be compared to the footprint trail Mary Leakey found at Laetoli, a discovery that demonstrated that three million years ago, the fully bipedal striding gait had been completely developed.
Nor are they the first fossil footprints found in South Africa. A set was found in 1966, in fossil dunes near East London. The CSIR is working now to determine the date of the “Nahoon footprints.”
But the Langebaan prints date to a time of growing interest to scientists – the point in prehistory that modern humans evolved, most probably in Africa.
Berger even suggests that the first human may have made her first appearance in South Africa – perhaps in the Western Cape.
“Whoever left these footprints has the potential of being the ancestor of all modern humans,” he said. “If it was a woman, she could conceivably be `Eve.'”
By “Eve” Berger means the hypothetical female of 100 000 and 300 000 years ago, from whom, geneticists theorise, all modern humanity may have descended.
Berger’s theory is that the southern tip of Africa, geographically and genetically isolated from the rest of the continent by deserts, mountains, and malarial swamps, was ideal for the emergence of new species of living things, including humans.
The idea is greeted largely with disbelief by Berger’s South African colleagues – “he’s out on a long limb” was perhaps the kindest comment, offered by John Parkington, professor of archaeology at the University of Cape Town.
Berger, the brash and energetic 31-year-old head of the palaeoanthropological research group at Wits University, is unlikely to be perturbed.
“What we are talking about is the possibility,” he said. “The prints are at the right date, they may be in the right place.”
In any case, the footprint find adds Langebaan Lagoon to an exclusive list of early human fossil sites. The fossil record from the age of human emergence is sparse, with no more than three dozen human remnants found in Africa – “they would cover half my desk” Berger said. Most have been found in South Africa.
Best known of the South African sites are Klasie’s River Mouth near Hermanus, where early humans sheltered between 120 000 and 60 000 years ago, Border Cave in the Lebombo Mountains near Swaziland, and Wunderwerk Cave in the Northern Cape.
“South African sites are among the most significant for fossil remains of anatomically modern humans… We have fossils, human fossils, actual skeletal material from several sites … that are amongst the earliest known remnants of anatomically modern people,” said Hilary Deacon, professor of archaeology at Stellenbosch University.
Archaeologists have found evidence in South Africa that the first humans engaged in such relatively sophisticated behavior as adorning themselves with red ochre “crayons.” They hunted dangerous animals, such as the now-extinct giant buffalo with a horn-span of nine feet. They fished in the sea, slept on grass mats, decorated the dead.
Langebaan is only one of a number of promising new sites in the Western Cape, Parkington said.
“A lot of them look as though they belong to the time period of 100 000 to 120 000 years ago. That’s an enormously interesting time period in terms of the origins of anatomically modern humans. There are a lot of possible directions one can go in, which have the potential of throwing light on the question of human origins.”
“Up the west coast we probably have an opportunity that is unique by world standards,” he said. “There is absolutely no doubt that the Western Cape coastal belt has enormous potential for researching the origins of anatomically modern people, and the origins of behaviourally modern people.”