Tracing back the evolutionary history of something is much like a detective sifting through the crime scene trying to make sense of it all; following the leads and joining the dots. The human evolution project – as far as studying it is concerned – is undoubtedly down to tons of fossil records that experts have accumulated and analysed over the last couple of hundred years.
However, the evolutionary history of perhaps one of the most ‘miraculous’ products of natural ingenuity the ‘Brain‘, is still somewhat of an enigma for science and is likely to stay that way unless we develop a method of tracing the evolution through a method other than fossil learning. The trouble with brains is that they consist of a very soft tissue, and soft tissue does not have the strength to survive millions or even hundreds of years of fossilisation.
Evolution of the brain has mostly been what is commonly known as ‘guess work’. Although soft tissue in the brain cannot survive fossilisation, the chamber that contains these soft tissues ‘the skull’ can however survive and is studied in order to expand our knowledge about the evolution of the brain. One aspect of the skull structure that widely contributes towards understanding a primitive brain is the size of the skull. This aspect has been studied widely; both palaeontologists and biologists agree upon the fact that the size of the skull directly relates to the size of the brain, which in turns relates to the cognitive abilities of the primitive animals.
Humans pride themselves for sporting big brains packed with some of the most complex cognitive abilities, that enabled us to walk on the moon and peak into the origin of our universe. Spread it across seven million years, and you will find that human brain has almost tripled in size, and most of this tremendous growth took place only in the last two million years. This much can be determined with an almost agreeable scientific precision, however getting to the nitty-gritty of the changes that the human brain underwent over the last couple of million years, is extremely tricky, to say the least.
Considering the significance of brains as the centre of our ‘being’ – not a philosophical standpoint as philosophers differ greatly about the precise location of the ‘mind’ which is the considered the software to the hardware called the brain – knowing the evolutionary journey of the brain is of paramount importance. Over the last 10,000 years, Human brains, in particular, have seen a sort of shrink which is considered an evolutionary enigma in and of itself. Experts point towards the shifting trends towards a more agricultural lifestyle that may have decreased the nutritional intake in humans, which may have contributed towards the shrinking of the brain.
In the last century or so, thanks to the industrial revolution the brain size has seen a significant rebound, another evolutionary enigma so to speak, courtesy of better childhood nutrition and a tremendous decrease in disease. When it comes to brains, and human brains, in particular, it is safe to suggest that learning about the past doesn’t predict the future of evolution. The integration of the brain with modern technology, which is increasing on a daily basis and the prospects of genetic engineering has the potential to essentially catapult the human brain into an unknown realm of evolution, and we have no way to predict it accurately.