A team of paleontologists led by Dr. Patrick Randolph-Quinney from the University of the Witwatersrand (Wits University) in Johannesburg, South Africa, and the University of Central Lancashire, UK, announced this week the discovery of the earliest evidence for cancer and bony tumors yet described in the human fossil record.
Image of the external morphology of a hominin foot bone (Paranthropus robustus or Homo ergaster) shows the extent of expansion of the primary bone cancer beyond the surface of the bone. Image credit: Patrick Randolph-Quinney.
Dr. Randolph-Quinney and his colleagues found a 1.6-1.8 million-year-old foot bone with definitive evidence of malignant cancer at the cave site of Swartkrans in the Cradle of Humankind, South Africa.
The bone belonged to an early hominin, either Paranthropus robustus or Homo ergaster.
The cancer was identified as an osteosarcoma, an aggressive form which usually affects younger individuals in modern humans, and, if untreated typically results in early death.
“Due to its preservation, we don’t know whether the single cancerous foot bone belongs to an adult or child, nor whether the cancer caused the death of this individual, but we can tell this would have affected the individuals’ ability to walk or run. In short, it would have been painful,” said team member Dr. Bernhard Zipfel, of Wits University.
This image shows the sixth thoracic vertebra of juvenile Australopithecus sediba. Top row shows surface rendered image volume. Bottom row shows partially transparent image volume with the segmented boundaries of the lesion rendered solid pink. Image credit: Paul Tafforeau, ESRF.
The same team identified a benign neoplasm tumor in the vertebra of the well-known type specimen of the extinct hominin Australopithecus sediba from Malapa, South Africa, dated to 1.98 million years ago.
The affected individual was male and developmentally equivalent to a human child of 12 to 13 years of age.
The oldest previously demonstrated hominin tumor was found in the rib of a Neanderthal and dated to around 120,000 years old.
“The presence of a benign tumor in Australopithecus sediba is fascinating not only because it is found in the back, an extremely rare place for such a disease to manifest in modern humans, but also because it is found 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,” Dr. Randolph-Quinney said.
“Modern medicine tends to assume that cancers and tumors in humans are diseases caused by modern lifestyles and environments,” said team member Dr. Edward Odes, also from Wits University.
“Our studies show the origins of these diseases occurred in our ancient relatives millions of years before modern industrial societies existed.”
“Not only has there been an assumption that these sorts of cancers and tumors are diseases of modernity, which these fossils clearly demonstrate they are not, but that we as modern humans exhibit them as a consequence of living longer, yet this rare tumor is found in a young child,” said team member Prof. Lee Berger, also from Wits University.
“The history of these types of tumors and cancers is clearly more complex than previously thought.”
The researchers reported their results in a pair of papers in the South African Journal of Science.
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Patrick S. Randolph-Quinney et al. 2016. Osteogenic tumour in Australopithecus sediba: Earliest hominin evidence for neoplastic disease. South African Journal of Science 117 (7/8); doi: 10.17159/sajs.2016/20150470
Edward J. Odes et al. 2016. Earliest hominin cancer: 1.7-million-year-old osteosarcoma from Swartkrans Cave, South Africa. South African Journal of Science 117 (7/8); doi: 10.17159/sajs.2016/20150471
