The human brain is shrinking and you didn’t know because…

‘Small-brained and big-mouthed’. A favourite rebuke of many a grandparent is perhaps not way off the mark. For the past 3,000 years, the human brain has been shrinking in size. This is one of the well-kept secrets of human anthropology, and researchers have been trying to find its explanations and implications.

A recent study co-authored by Dr Jeremy DeSilva from Dartmouth College notes that human brain size steadily grew until an abrupt reversal around 3,000 years ago. Since then, the human brain size is growing smaller and smaller. At this rate, in the next 20,000 years it would be comparable to those found in our ancestors, Homo Erectus, who lived about two million years ago.

Hold your horses, a bigger brain is not necessarily brighter nor the erosion of our grey matter is a result of our penchant for the idiot box. The authors say that the downhill journey of the human brain size is timed to the emergence of ancient river valley civilisations around the world and the consequent changes in the lifestyle of humans.

With the onset of the agricultural revolution, humans predominantly inhabited settlements around agrarian lands rather than dwelling in forest caves. In contrast to chasing games in the forest, crops were cultivated and animals were reared for food. Dense forest patches were cleared to create agricultural lands.