Trip to Sterkfontein

We took trip to Sterkfontein, the site called the Cradle of Human kind. The site is situated on the Gauteng province in South Africa. The Sterkfontein Valley landscapes in Western Gauteng and North West province consist of a band of important paleo-anthropological sites. This site has been nominated by the Gauteng’s provincial government as one of the world’s heritage list. The site covers 47 000 hectares of land and comprises a strip of a dozen dolomite limestone caves containing the fossilised remains of plants, animals and hominids.

The Sterkfontein caves are located within the Isaac Edwin Stegmann Reserve about 10 km from Krugersdorp. These caves were donated to the University of Witwatersrand by the Stegmann family. The dolomite from which the cave is formed started out as coral reefs growing in a worm shallow sea about 2,3 billion years ago, as the reefs died out they were transformed into limestone where after some time was later converted into dolomite. A section of the cave is open to the public and there is a gravel platform from which the public can view the excavation site. There is a tea room and a small museum in which information about significant findings are on display.

Findings along the way to the cave

On the way to the cave there are beautiful tombstones of different species and Rufus was explaining each of them to us, these include a Bakteria Rock with fossil bacteria from Mpumalanga which was discovered 3.500 million years ago, Ceolacanth fossil which was the first fish to walk in four legs some 300million years ago, Lystrosaurus a mammal like reptile from karoo it was a vegetarian some 2.4 million years ago, Dinosaur Euparkeria Archosaur is discovered some 2.200 million years ago, Australopithecus (foot) which is the direct common ancestor of homo habilis was discovered some 3.3 million years ago, Mrs Ples(Australopithecus africanus) is estimated to be between 2.8 and 2.6 million years ago, Homo Neanderthalensis the first specie to talk and sing and a place called Swartkraans which is the first place where fire was discovered in the whole world by Homo sapiens.

The cave itself

We were told that the cave consists of two entrances the one is man made and the other is naturally made. The natural one was used by the different species where they got inside the cave hoping that there will be a way out but unfortunately they were trapped there and some died because of hunger and became fossilized. The man made entrance consist of steps which are also man made and there is electricity inside but Rufus also used the torch. There are different pathways going to different directions and we were advised to remain with the group every time to avoid getting lost. The cave is so beautiful inside and its walls are beautifully shaped, the temperature is moderate and the place is very tidy. At the entrance there is a video stand. We watched the video about a little foot at which professor Ron Clark was explaining that there is a skull which is still embedded on the rocks. The whole skull is said to be about 3.3 million years ago. In the middle of the cave there is a very nice stream with very pure water, this is the centre of the cave which is not safe. There is no enough about this stream because people have tried to research it but some end up loosing their lives there.
At the cave exit there is a very beautiful statue of Dr Robert Broom carrying a skull of Mrs Ples.

The Museum

Different types of hominid fossils were observed at the museum including humans, chimpanzee and gorillas. Parts such as teeth, skulls, bones and stone tools were also found and all the fossils were labelled according to their years of existence.
At Sterkfontein there are different methods of dating that they use to determine how old their discoveries are:
Uranium- series dating relies on the analysis of the changing ratios of uranium and lead in the cave deposits. It has been used to date in fills and stalagmites.
Cosmogenic - involve analysis of isotope of elements such as beryllium and aluminium. This method has been used to obtain a date of about 4.1 million years for the “little foot” although paleomagneticism dating places it slightly young.
Paleomagnetism- Is a method used date deposits at Sterkfontein and other humankind sites
Comparison- estimates of the age of hominids from the cradle of Humankind can be obtained by comparing them and associated animal remains fossil from East Africa that were found in association with volcanic ash deposits.
Cutting edge of science- Specific ages of difficult to determine as methods of dating and knowledge of contextual evidence are constantly being refined and updated. The University of Witwatersrand’s Professor Tim Partridge a world expert on this issue explains “A date obtained one month may be completely different to that calculated next month; we’re on the cutting edge of science so things are bound to change all the time.

From the whole trip I have learned that it is important to listen to other people like Rufus the tour guider because he knows everything about the cave. So we all followed his instructions and we arrived safe. This journey also gives me the confidence to be curious, when I think about all the work these scientists have gone through to get these fossils just believe that I can now be a real researcher myself.

Dianah Nangammbi
Cilla CSIR
P.O Box 395
Pretoria
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Tel: +27 12 841 2133
Cell: +27 73 121 3589
Email: dnangammbi@csir.co.za
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