The earliest evidence of cancer in the human fossil record has been discovered in a cave in South Africa, an international team of scientists have told to BBC news service.
The aggressive tumour was found in a 1.7 million-year-old toe from an ancient human ancestor.
The toe belonged to one of the early hominins, either Homo ergaster or Paranthropus robustus.
The researchers said the findings clearly show cancer is not a disease of modern society, as some people claim.
Tumours have been detected in remains before - a Croatian Neandertal who walked the Earth around 120,000 years ago was one of the oldest.
The new discovery was made in a toe bone from Swartkrans cave in the Cradle of Humankind World Heritage Site near Johannesburg.