From 1945 onward, he and his colleague, John Robinson, used controlled explosions to extract more fossils.In 1957, Dr CK “Bob” Brain of the Transvaal Museum found stone tools in a miners’ dump and Robinson and Revil Mason used a grid system to excavate in the stone tool area.Sterkfontein has produced some of the most famous hominid fossils in the world, together with a range of other fossils of animals and plants.The site has a very high concentration of fossils – the highest in the Cradle of Humankind – which, as a whole, has produced more fossils of early hominids than any other site on Earth.Our knowledge of human evolution is changing rapidly, as new fossils are discovered and described every year.Thirty years ago, it was generally accepted that humans and the great apes last shared a common ancestor perhaps 16-20 million years ago, and that the separate human branch was occupied by only a few species, each evolving from the one before.

Sterkfontein is home to one of the world’s longest running palaeontological excavations.

Now we know, through a combination of new fossil finds and molecular biology, that humans and chimpanzees diverged as little as 7 million years ago, and that our own lineage is "bushy", with many different species in existence at the same time.

Our view of our evolutionary past has changed as social attitudes have changed.

This interpretation reflected the prevailing prejudices about human ancestry, and was supported by misinterpretation of the remains of the "Old Man of La Chapelle", whose skeleton was warped by arthritis.

Even when the idea that apes and humans shared a common ancestor became more widely accepted, the concept of an African origin was not.