Named "Little Foot", the skeleton was found about 40 kilometres outside Johannesburg by miners, blasting rocks inside the Sterkfontein caves. "It was like excavating a fluffy pastry out of concrete", Prof Clarke said. Even then, Clarke surmised that the fossilized bones came from an Australopithecus species - the smallish, ape-like human ancestors that roamed this part of Africa millions of years ago. Because that's how it started, with one little bone.
Lucy and Little Foot both belong to the Australopithecus genus but are separate species.
Professor Ron Clarke taking a closer look at Little Foot.
The team of researchers associated with the study has displayed the nearly complete fossil of Australopithecus on Wednesday.
Paleontologists in South Africa have unveiled one of the absolutely complete skeletons of a human ancestor, which dates back 3.6 million years.
The exact age of the skeleton remains a mystery, but it is believed to be around 3.67 million years old. Within two days of searching, they found such a contact, in July 1997.
In the 20 years since the discovery, they have been hard at work to excavate and prepare the fossil.
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Now Clarke and a team of worldwide experts are conducting a full set of scientific studies on it.
Twenty years after the initial discovery, the process of excavation, cleaning, reconstruction, casting, imaging and analysis is complete, and researchers are ready to reveal Little Foot to the world.
The find reinforces the belief that South Africa was a major cradle of human evolution, featuring diverse hominid ancestors.
"The process required extremely careful excavation in the dark environment of the cave". The results of these studies are expected to be published in a series of scientific papers in high-impact, peer-reviewed global journals in the near future.
"My assistants and I have worked painstakingly ever since, cleaning the bones from the breccia blocks and reconstructing the full skeleton", said Clarke. "And it helps us to understand our origins", Prof Clarke said.
Radio 702's Azania Mosaka spoke to Professor Robert Blumenschine, the chief scientist at the Palaeontological Scientific Trust, about Little Foot.
Blumenschine added that the discovery indicated that Africa is more than the storehouse of the ancient fossil heritage for people the world over.