Over 4 billion years ago, scientists say the earth was a ball of burning gas spinning through space. Super-heated gases could escape into space at first. However, as the planet cooled, gravity held the gases together to form the early atmosphere.
It took millions of years for the first masses of land to appear after the oceans had formed. The supercontinent called Pangaea formed as early as 250 million years ago. Pangaea then broke up into two continents – Laurasia in the north and Gondwana in the south.
Continental drifts often occurred, causing earthquakes and tsunamis. As a result of these drifts, the Indian subcontinent broke off from the east coast of Africa. It moved to the north, slamming into Asia and creating the Himalayas. This effect of this on Africa’s climate was profound. Air currents became drier, resulting in reduced rainfall. This dry climate caused savannahs to replace forests.
Scientists say that the first living organisms were cyanobacteria. They appeared on earth over 3 billion years ago. These cyanobacteria made layered structures called stromatolites. The structures emerged after the earth cooled, and the atmosphere and oceans formed.
Scientists have found fossil traces of some of the world’s oldest stromatolites, which are about 3 billion years old. They found these in South Africa near Barberton in Mpumalanga, and in Sterkfontein in Johannesburg. They also discovered other stromatolite fossil traces in north-western Australia and Greenland.
From what geneticists have found, Africa is the birthplace of humankind. They have done tests on specific African populations in East and Southern Africa. They found with the Khoi/San people of Southern Africa that they have more variety in their mitochondrial DNA than in populations living outside Africa.
Mitochondrial DNA transmits only from mothers to their children. It passes almost unchanged from generation to generation.
The geneticists’ discovery means that people groups from Africa have existed for many generations.
The DNA studies match with fossil discoveries that scientists have done. The studies suggest that human life has been existing in Africa longer than in any other place. Scientists discovered evidence of the oldest fossil of human life in Ethiopia and South Africa.
These discoveries support the Out of Africa theory. This theory argues that humans originated in Africa. They then spread to populate the rest of the world.
Archeologists have found fossils of hominids in Southern Africa, Ethiopia, Kenya, and Tanzania. They believe that these are the fossils of the earliest ancestors of humans.
The Taung Child is an extraordinary fossil discovery that archeologists found in 1924. They discovered the fossil in South Africa’s North West province. It had an ape-sized brain and human-sized teeth.
Another significant discovery was the fossil of Little Foot. Archeologists discovered this fossil in 1997 in the Sterkfontein Caves located in Johannesburg. They measured that Little Foot lived approximately 3.7 million years ago. The skeleton’s 32 teeth were intact when archeologists found it.
The Sterkfontein Caves
Since the 1930s, archeologists have found over 9,000 specimens in the Sterkfontein Caves. The caves are the biggest in the world for archeological discoveries.
There were no remains of ash or rock paintings found in the caves. Archeologists believe that hominids didn’t live in the caves, but instead fell into them by accident.
As you descend into the caves, you’ll see beautiful rock formations that are a work of art. The caves’ temperature remains at a cool 18 degrees Celsius.
You’ll see the exhibition of discovered hominid fossils at the Maropeng Visitor Centre. You’ll also see exhibits that detail the formation of the earth and the evolution of human life. The centre is open every day from 9 am to 5 pm.
The Sterkfontein Caves are a 10-kilometre drive from the Maropeng Visitor Centre. Visiting times are every day from 9 am to 5 pm, with the last guided tour departing at 4 pm.
The best ticket to get is the combination ticket. With this ticket, you’ll gain access to the Maropeng Visitor Centre and the Sterkfontein Caves. The cost is R190 ($14) for adults, R125 ($9) for children under 18 years and R65 ($5) for pensioners. School groups pay R120 ($9) per pupil.
Make sure to wear comfortable clothes and sneakers when visiting the caves. There’s much walking that you do when exploring.
If you’re claustrophobic or suffer from chest problems, Maropeng advises that you don’t go down into the caves.
No pets are allowed at Maropeng and the Sterkfontein Caves, except for service dogs and guide dogs.
For contact details, directions and more information about ticket costs, click on the Maropeng site here.
* images are mine. Banner image from Creative Commons.