Rick Hunter and Steven Tucker set out that day of 2013 to look for fossils in unexplored parts of the Rising Star Cave about one hour north west of Johannesburg in the Maropeng area. Meticulously exploring the well-known dolomite cave, they found a narrow vertical tunnel. Taking this chute feet first they discovered a chamber 30 metres below ground filled with bones. These could be just any bones, but when they came head first with what looked like a human mandible, they knew they were onto something big…Most of what we know about our origins has been found out by studying fossils of our ancestors, known as hominids. A fossil is the remain of a plant or animal that has been preserved in sedimentary rocks. However, it is not that easy to get fossilized, and every animal that dies has only a chance in a million to end up fossilized. Chances are far greater here in the Maropeng area dotted with about 300 caves where the right mix of conditions promoting fossilization are met: thousands of fossils of hominids and animals have been found in what is referred to as the cradle of humankind. In the Sterkfontein Cave only, many fossils have been found, including the 3-to-4-million year old Little foot as well as the oldest stone tools in Southern Africa. Little Foot was a 30-year old who died by falling into the cave: its whole skeleton could be recovered… after 15 years of meticulous excavations! And this discovery has been invaluable for the scientific world as it is the only complete Australopithecus skeleton ever found.
Given the background of the place, one can imagine that Rick and Steven were pretty excited that day… After visiting some scientists, and a Facebook ad later, an international team of 6 women preferably skinny and short was formed: the Rising Star expedition’s advanced cave scientists. Lindsay Hunter who fits the bill was one of them. The excitement is still visible in her eyes as she describes how they reached the Dinaledi chamber where the bones were found, about 80 metres from the cave entrance after the chute and crawling through narrow channels. It took them about 30 minutes to reach the chamber through the 2.3-billion-year old intricate cave that was formed over millions of years by acidic groundwater or underground rivers dissolving away the limestone leaving place for cavities which have grown over time. Once in the dark chamber, they had been working with delicate tools like plastic spoons, paintbrushes and toothpicks to slowly free the fossils from the cave. As Lindsay puts it, this was like playing pick-up stick at expert level: bones were packed in a cube of 50 centimetre side. Millimetre by millimetre the bones belonging to about 15 individuals had been released. We are standing by a chimera (the reconstruction of a skeleton with the bones of various individuals) made from these bones. Lindsay explains that the skeleton is close to the ones of gibbons with very curved hands, maybe for climbing? These bones still have a lot to tell us as this priceless discovery is still being researched. Based on their size and structure, the shape of the specimen and the size of its muscles or even its diet can be known.
More surprises were to come. When the team of cave scientists expected these specimens to be one of our ancestors, it turned out that they were only 236,000-to-335,000 year old, making them our contemporary (homo sapiens are 195,000 years old). A new specie had just been discovered: the Homo Naledi!
If more exciting findings will be made thanks to this exceptional discovery, the cradle of humankind has not revealed all of its secrets yet as another chamber in which even more hominid fossils are present is being explored. What secrets does the Lesesi chamber hold?
Marcella & Claire
- The cradle of humankind is a very interactive visitors’ centre retracing the history of the planet from its formation 14 billion years ago to the evolution of hominids all the way to modern humans.
- The Sterkfontein Caves where many hominids have been discovered can be visited and complements the cradle of humankind.
- Check out this interactive map for the specific details to help you plan your trip and more articles and photos (zoom out) about the area! Here is a short tutorial to download it.