Who are we? Where do we come from? Anthropologists, historians and archaeologists have traced our origins back to millions of years. With our persistent courage and insatiable curiosity, we have made tremendous strides towards finding the source of our being.
Religion, over the course of history, played a major role to assuage mankind’s thirst for knowledge on these salient issues. Ancient Sumerian texts on human origins are rather fascinating.
They tell us that Earth was once ruled over by human-like Gods. When these Gods came down to Earth, they started toiling in the soil to make it habitable for agriculture and mining of minerals. But the Gods mutinied because the labour was too great. Anu – the supreme God of the Sumerian pantheon – agreed and devised a plan to shift the burden of hard labour to someone else. His son Enki, to whom we will always be grateful, proposed the idea of creating Mankind who would bear the labour while the Gods watch from the heavens.
So with the help of his half sister Ninki he created the first humans. A God was sacrificed and his body & blood were mixed with clay to give shape to the first man.
Tales something along the likes of this sprung out everywhere, in vastly different cultures who followed vastly different religions. But even though we are not privy to the information surrounding our origins as a rudimentary life form, we have been able to track our evolutionary journey through time.
Mankind’s transformation from mere hunter gatherers to building a civilisation and leading a sedentary life is one such extraordinary journey. The picture that is drawn by the historians show us a man who first became a hunter, then a fisherman, then a farmer, subsequently becoming migratory or nomadic, then eventually a settler.
The earliest hominine fossils were the 4.5 million years old remains of Ardipithecus ramidus that were discovered in the Afar region in Ethiopia. But there is better evidence for the later emerging Australopithecus afarensis – one of the best known early human species. Their fossilized footprints, dated somewhere between three to four million years ago, stipulate utilitarian if not fully functioning bipedal gait, hands that are partly adapted to climb trees and brains that are approximately one-thirds the size of ours. This species is believed to be ancestor of both the Australopithecines boisei, athiopicus and robustus.
Evidence of evolutionary trends in our genum – Homo, stretches back to somewhere between two and three million years ago. Our brains became bigger. This process is known as encephalization. A larger brain requires a better diet to sustain it. The aforementioned Australopithecines had large teeth and ate herbivore diets. The hominines evolved to have larger brains but maintained an overall same body size, with little to no change. As evolution would have it, the growth of brain resulted in the reduction of another organ – the stomach. This reduced the efficiency of the digestive tract making a better diet even more imperative.
Subsequently, the hominies moved towards a protein and energy rich diet. Sharpened stone tools found in Ethiopia and dating back to some 2.5 million years ago suggest that meat was a central part of the diet. These sharp objects were used to cut through flesh and to pound the bones that are rich in marrow. There is also evidence of cooking after archaeologists uncovered burnt bones in southern Africa. The smaller stomachs would need the animal proteins to be broken down before digesting, ergo the burning of the flesh.
1.8 Million years ago, the Homo erectus colonised large swaths of lands outside of sub-Saharan Africa. Around 500,000 thousand years ago, the Homo heidelbergensis migrated towards northern Africa and reached northern Europe about 400,000 years ago. The Homo erectus and heidelbergensis are believed to have shared a common ancestor known as Homo ergaster.
The Homo ergaster is perhaps best known from the Turkana Boy – a nearly complete skeleton of a youth found in Nariokotome in Kenya. The boy is believed to have lived during the early Pleistocene or the Ice Age.
By 1.5 million years ago, all three aforementioned species had adapted to technology. They built hand axes which they had sharpened giving them a distinctive edge. They had various other stone tools that they used in their day to day life. Their brain sizes grew as well. Are both of them related?
Perhaps not, as the Australopithecines also used stone tools but their brain sizes remained the same and neither did they migrate out of Africa. Homo’s growth in brain size is a result of using the brain. The hominines used the brain to remember, to organise, to memorise – unsurprisingly, evolution kicked in.
As the hominines learned to use their brains, they simultaneously built social structures. They learned that they can survive in small groups just as well as a massive tribe travelling together. This resulted in groups splitting off of the main tribe and journeying towards unknown, even harsher, habitats and giving birth to the earliest colonisers.