We can start the story of mankind around 50,000 years back. Every story has to start at some chosen arbitrary point of time. However, without a broad look at events prior to that date we may not realise the richness and the complexity of human evolution and journey of man through both, space and time. The attraction for simplification may divorce us from a proper appreciation of the available evidence.
Five Million Years in the Making
By way of a brief recap, the journey out of Africa 50,000 years back, was of a branch known as homo sapiens or modern man. He was, however, not the only man-like species known to us. Prior to homo sapiens another – more primitive – species called homo erectus had also initially evolved in the same general area of east Africa and, had also migrated out of Africa, and is referred to, in popular literature, as the ‘cave man’ or the Neanderthal. He was already there in Europe by the time homo sapiens arrived and because of climatic change and superior technology of the competing homo sapiens, homo erectus went extinct. Recent researches also indicate that homo erectus may have simply cross-bred with newly arrived, technologically superior, homo sapiens and in that sense ceased to exist as a separate identifiable species. One must also note that homo erectus was not the only other man like species known to us today. Recent findings indicate a dwarf ‘Java man’ and a far more robust and heavily built ‘Siberian man’. These are just the known instances. There could be many more.
East African Savannahs : The Cradle of Man
All evidences available till now reconfirm east Africa as the cradle of human species. In present times, it has only one ape and several monkey species but, long ago, say four million years back, there were dozens of different ape species in that area. Geography precedes history. The ape species multiplied in that era because the land was gradually drying up – similar to the present day global warming – and the large trees were finding it more and more difficult to grow. The empty spaces between the scant tree cover was taken over by the grasses. As usual, the slow paced creeping evolution of the landscape was sent into an overdrive by a cataclysmic event. Ngorongoro volcano, in the present day Tanzania, erupted some two million years back and its ash covered the surrounding and pre-existing Great Rift Valley. The trees were burnt down or smothered by the ash, which, compacted by the rains, would permit only short-rooted grasses to thrive. Thus the famous Savannahs of east Africa were born.
Adapting to the Newly Opened Landscape
Animals had to adapt to these geological changes and the survivors were those that successfully adapted to fit into the new environment. Most apes had the capability to stand upright – on two legs – briefly. Anatomical changes and acquired behaviour gradually gave some of these apes the capacity for upright movement over long distances. Such upright posture was favoured in the evolutionary trend because, with upright posture, they could watch out for both danger and for food over the top of the grassland right up to the horizon. It also freed their arms from supporting the body weight while moving, and thus, opened up the possibility of carrying food in their free arms, over long distances, developing greater flexibility and sensitivity in the hands and, further down that evolutionary path, creating the potential for the subsequent development of tool making and tool using capacities.