(AGI) - Cape Town, Jul 29 - The discovery of a foot bone approximately 1.7 million years old, with definitive evidence of malignant cancer, pushed the oldest date for this disease back from recent times into deep prehistory, South Africa's University of the Witwatersrand (Wits) said in a statement on Thursday. The find, published in the South African Journal of Science's July/August issue, shows that cancers and tumours plagued human ancestors for millions of years, challenging the assumption that they are caused by modern lifestyles. The research was conducted by a team of international scientists, led by Wits's Evolutionary Studies Institute and the South African Centre for Excellence in Palaeo Sciences. The bone was found in the Swartkrans cave, in the Cradle of Humankind, about 50 kilometres northwest of Johannesburg in South Africa's Gauteng province. The exact species to which the foot bone belonged was still unknown, but it was clearly a hominin, or bipedal human relative, the university said.
In an accompanying paper in the same journal, researchers also identify the oldest tumour ever found in a human fossil, a benign neoplasm found in the vertebrae of the well-known Australopithecus sediba child, Karabo, at the Malapa site, also in the Cradle of Humankind. It was dated to around two million years in age. The oldest previously demonstrated possible hominin tumour was found in the rib of a Neanderthal and dated to around 120 000 years old. "Our studies show the origins of these diseases occurred in our ancient relatives millions of years before modern industrial societies existed," said Edward Odes, a Wits doctoral candidate. "Karabo's tumour was fascinating because it was in the back, an extremely rare place for it to be found in modern humans, but also because it developed in a child. This in fact is the first evidence of such a disease in a young individual in the whole of the fossil human record," said one of the researchers, Dr Patrick Randolph-Quinney of Wits and the University of Central Lancashire in the UK. Professor Lee Berger said the evidence of a tumour in a child questioned the assumption that modern humans developed them as a consequence of living longer. Both incidences of disease were diagnosed using state-of-the-art imaging technologies at the European Synchrotron Research Facility in Grenoble, France, medical CT at the Charlotte Maxeke Hospital in Johannesburg, and the micro-CT facility at the Nuclear Energy Corporation of South Africa. (AGI) .