Thursday, 6 February 2020 - South Africa
Today I visit the Cradle of Humankind. It stretches over an area of about 470 square km that is dotted with about 300 caves. Inside the caves there are thousands of fossils of hominids and other animals, dating back to about 4 million years, to the very birth of humankind! How exciting! The whole area known as the Cradle of Humankind has been declared a World Heritage Site by UNESCO in 1999. The most famous fossil found here is ‘Mrs Ples’, a skull more than 2 million years old, and ‘Little Foot’, a skeleton which is between 3-4 million years old.
First I went into the Sterkfontein cave. This cave started forming about 20 million years ago, and is mostly made out of dolomite (a soft sedimentary rock). There are many caves here but this is the only 1 which is open to the public. We walked 60 m down, where the temperature was about 18 degree Celsius. More than 40% of hominid fossils of the world are found here; there are more than 9,000 fossils here. Fossils are remains of plants and animals that have been preserved in sedimentary rocks and formed over time as organic material is mineralised into stone. A ‘Hominid’ is a bipedal primate i.e. can walk upright on 2 feet. There are also stone artefacts found that are up to 2 million years old, which are the oldest dated stone tools in South Africa.
As mentioned before, the most famous hominid fossil here is known as ‘Mrs Ples’ - (short for Plesianthropus transvaalensis which means “almost human from the Transvaal”). It has features of both human and ape as well. Now it is classified as Australopithecus africanus (southern ape of Africa), a distant human relative which lived more than 2 million years ago in the Cradle of Humankind. It is called ‘Mrs’ because they thought it was a female due to the small brain cavity and small socket for the canine teeth. But some others argue it may have been a young boy. The fossil’s human-like features included the ability to walk upright, and a brain only slightly larger than a chimpanzee. The “Taung child” (not found here) is another example of Australopithecus africanus; it is a 4 year old child with ape-sized brain and human teeth. But this was found in Taung, the North West Province of South Africa.
Walking through the cave and to the place where another famous fossil was found - ‘Little Foot’. The fossil was mummified before being covered in sediments, and was subsequently calcified and preserved in breccia for millions of years. So the skeleton is almost complete, which is rare. He is one of the most ancient human ancestors yet discovered, at 4.1 million to 3.3 million years old. He is smaller than most modern humans and had a smaller brain. He walked upright but had powerful hands and a slightly divergent big toe; so he was probably still good at climbing and slept on trees. Scientists believe that he may have accidentally fallen down into the cave because there were many openings into the cave which cannot readily be seen from above ground; perhaps also because he was just making the switch from living on trees to walking upright on 2 feet and therefore not very stable yet.
Finally we reached the point of the cave where there was an underground river. This is quite cool but there are also pretty strong currents here and there is at least one diver who lost his life exploring the depths of this underground river. Then the trek back out of the cave which was easy enough but you really had to bend and crawl at some places which was pretty cool!
From the cave I went to the museum of the Cradle of Humankind which had loads of information about the beginning of the world, the changing landscapes of the world as well as the birth of the various species, humankind included. There was something like a raft that you have to ride to get to the exhibition theatre, and this was really fun but quite scary at first because as usual I was alone and didn’t know what the hell was going on! And of course if the raft crashed into the water there was no one I could turn to for help but fortunately nothing of the sort happened.
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