The Evolution Of Hominids
The discovery of important hominid fossils in South Africa,contributing to the scientific debate of the emergence of humankind in Africa.
“ It is probable that our early progenitors lived on the African continent.......”
Charles Darwin (1809 - 1882) author of “On the Origin of Species”.
These words caused consternation among horrified Victorians in the middle of the 19th century. Their horror was further compounded by Darwin’s postulation that human beings shared a common ancestry with apes. As one appalled Victorian lady was heard to declare “My dear let us hope it is not true, but if it is, let us pray that it will not become generally known.”
But it did become generally known, and with time Darwin’s hypothesis has been proved by recent findings. With the advent of the science of DNA and genetic testing it has been shown that humans share 98% of their genetic make-up with chimpanzees; making this intelligent and dexterous ape our closest living relative.
It stands to reason then, if humans and apes did share a common ancestor millions of years ago, that human beings would have originated in Africa, where the great apes are found.
Modern science has vindicated Darwin on both counts!
It is commonly accepted today that our earliest ancestors evolved in Africa millions of years ago. When the many fragments of bone and fossil are put together they show a creature which was a bit like a chimpanzee and a bit like people of today.
Does that mean that modern people come from apes? “No”, say the scientists. What it does mean is that about 8 million years ago monkeys, apes and humans shared a common ancestor. This common ancestor is the great-great-great-great-great-great-great-great-great-great (times a few 100,000 !!) grandmother of chimpanzees, monkeys, baboons - and people.
Some members of this common ancestor developed into monkeys and apes, while other members of the same ancestor went on to develop into humans.
This evolution took place over many millions of years. Our early hominid ancestors walked upright on their hind legs like we do, but their brains were smaller than our brains are today. Their teeth were more like our teeth than monkey teeth. Their arms were slightly shorter than a chimp’s arms and were used to climb trees when they were threatened by other animals. They still had opposing toes like apes have; the opposing thumb developed much later when hominids began using tools.
Some scientists suggest that the opposable thumb, and tool making, pre-empted upright locomotion, while others suggest that upright locomotion gave our ancestors the opportunity to use and make tools.
In 1925 a man named Raymond Dart was given an ancient skull. The skull was that of a creature that was midway between ape and human. By chipping away at the rock around the skull, Dart found the upper and lower jaws of a face, as well as the brain cast of a creature previously unknown to science. Dart could tell that this was not the face of a baboon nor any other kind of ape. It was the face of a 4 year old hominid baby who had died about 2.8 million years ago. Dart named the skull the Taung Child after the place at which the skull was found.
Sometime after the discovery of the Taung Child a man named Robert Broom found an adult skull much like the Taung Child’s, but the teeth were different (Paranthrapus robustus). A while later he discovered yet another skull with much larger, more humanlike teeth (Australopithicus africanus). It soon became clear that in the very distant past there were different kinds of hominids all living near each other at the same time.
Some of these creatures were more humanlike than others. Scientists believe that the more humanlike creatures probably hunted and killed the creatures that were more apelike. In the Swartkops Valley just outside Johannesburg there are many lime filled caves where important fossil and bone discoveries were made. These discoveries helped scientists to understand how modern humans developed from hominids.
Some of these discoveries were made by Professor Philip Tobias, and by Dr. Ron Clarke who discovered “Little Foot”. They demonstrate how over time hominid jaws, teeth, brains, arms and legs changed until they became more like those of human beings today. Other important evolutionary changes are are:
· hominids began bipedal locomotion (they walked upright on two legs)
· their brains became bigger
· they developed opposing thumbs
· they began using and making tools.
If you were to travel back in time to the South Africa of 50,000 years ago, you would meet the very first South Africans. These were true humans (Homo sapiens) who lived along the Cape coast. Scientists have found evidence of these early South Africans buried deep in the soil around the Cape coast. They were the ancient ancestors of the San peoples. Many other ancient San lived inland. Sadly, there are not many San left today. Those few that are left live in small family groups in the Kalahari desert.
The ancestors of today’s remaining San lived during the Stone Age. They were hunter-gatherers who did not domesticate animals or grow their own crops. They are well known for their beautiful rock art found in caves around South Africa. Experts believe that these mysterious pictures show scenes that are spiritual in nature. They refer to the shamanistic aspects of ancient San religion and culture. These paintings illustrate trance and transference states in which the individual undergoes a mystical experienced.
The San used animals to portray shamanic power. A shaman’s positive power was depicted by buck, most often the male Eland. This animal, with its large deposit of fat around is neck, symbolised wealth, riches and power. Negative or abusive shamanic power was illustrated with images of hunting animals like lions, leopards and cheetahs.
Some examples of San Rock Art are between 25,000 to 30,000 years old. They are an important record of life in South Africa before the first black farmers and white settlers arrived.