Think the paleo diet protects you from cancer? It might, but researchers in South Africa say they have found a cancerous foot bone that's about 1.7 million years old.
Although the exact species could not be determined, scientists say the bone was from a hominin -- a bipedal human relative -- who presumably ate a diet that could be described as paleo, consisting mostly of meat, fish, fruit and vegetables, or whatever else could be chased down or plucked from the ground.
The discovery is said to be the most ancient evidence of cancer yet found and pushes the oldest known incidence back from modern times into deep prehistory. The oldest previously demonstrated possible hominin tumor was found in the rib of a Neanderthal and dated to around 120,000 years old.
"Modern medicine tends to assume that cancers and tumors in humans are diseases caused by modern lifestyles and environments. 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 doctoral candidate at the University of the Witwatersrand's Evolutionary Studies Institute.
Would have been painful
The cancer in a foot bone, a metatarsal, was identified as an osteosarcoma, an aggressive form of cancer 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," says Dr. Bernhard Zipfel, a Wits scientist and an expert on the foot and locomotion of early human relatives. "In short, it would have been painful."
The findings were published in the South African Journal of Science.