Last year a study was widely circulated in which scientists claimed that the human brain has shrunk. This was the result of our transition into living in more complex, urban societies, according to anthropologist Jeremy de Silva of Dartmouth College, US.

Hard on his heels came a study this year from the University of Cambridge showing that the brain should be shrinking as the world warms. What a calamity.

What will happen to our civilization, our societies, our nations, our capacities, our brains? Having long treasured, even fostered the human mind, have we truly cherished the miracle of survival? Is not man his mind?

A buzzing bee discovered joyfully: “Brains are awesome. I wish everybody had one.” And is the mind the brain?

We know where the brain is. It is the organ or grey matter in our skull, weighing about 1.3-1.4 kg, 60 per cent fat, 40 per cent a combination of protein, carbs, and salts. The mind uses the brain and the brain responds to the mind. We know where the brain is, where is the mind?

The mind has no properties. The mind occurs, exists, and functions with the brain. They are a unity. The welfare of the brain is our concern.

Experts from all corners of the globe are in concert about the present health of the human brain and most agree it may be in jeopardy.

Paleoanthropologist Ian Tattersall of the American Museum of Natural History, New York City, tracked the braincase volumes of ancient hominins (ancestral humans) through time. It started with the oldest known species and ended with modern humans. His result is that skulls are an average 12.7 per cent smaller than that of Homo sapiens who lived during the last Ice Age. The shrinkage corresponds to the spontaneous inventions of language.

As smaller and better organised brains were able to perform more complexities, larger brains simply became unnecessary. That is a sigh of relief.

Other paleoanthropologists argue that the change could not be linked to language. There is no data to show that there was a decline 100,000 years ago, argues Jeff Morgan Stibel of the Natural History Museum in California, but a change of climate and not language could explain our smaller brains. “What we saw was the warmer the climate, the smaller the brain size in humans.” Should we at present, be concerned?

Brain weighs about two per cent of our body mass but consumes 20 per cent of our resting metabolic energy. The theory is that smaller brains dissipate heat better and have a reduced heat output.

So far so good, but in today’s rapidly warming planet, could our brains shrink even further?

Theories abound. The most prominent theory put forward to explain our shrinking brains come from the famous anthropologist De Silva, when hunter-gatherers laid down roots and began to build complex societies. Complex minds should accompany complex societies, but the result was quite the opposite.

De Silva calculated that our brains started shrinking about 3,000 years ago at around the same time that complex civilisations began to emerge. This was the Bronze Age, an era which witnessed the appearance of Egypt’s New Kingdom, the development of Chinese script, and the Trojan Wars.

Such a notion sounds odd at best.

The arrival of more complex societies, the invention of languages and other theories aside, all we know is that back then brains were larger and they are about 1.3 per cent smaller today. Is there a problem?

If brains are shrinking, what does this mean for human intelligence?

Depending on which theory you believe, smaller brains could either make us smarter, dumber or have no effect on intelligence.

The new consensus is that there have been no changes in the human brain, whether 3000, 30,000 or 300,000 years ago. Rejoice. There is no reduction in brain size in modern humans over anytime period since the origin of the species. Hurrah.

We are grateful to anthropologist Brian Villmoare and Mark Grabonski of the Human Paleontology Laboratories.

“Brain size isn’t everything.” Einstein’s brain weighed only 1,230 grammes, less than the average adult male brain. Weight has little correlation with intelligence. What a sigh of relief.

What Einstein had was more nerve cells, or neurons, those “hard working, fast-firing micro- machines” which network together and make up everything from the memories we retain to the personalities we display.

Einstein had a brain that was so unusual that is unlikely to have ever existed at any time throughout the history of man. Why fuss over the size of the brain?

It is pertinent to mention that women and men have similar cognitive abilities, even if the male brain is 10 per cent larger, it does not impact on intelligence.

As we have undergone change since our species first evolved, as in the decrease in our bodies, then it stands to reason that our brains have likewise decreased. Our brains are now the smallest they have been at any time in the past 100,000 years.

Ageing is the hateful cause for shrinking the brain size as well as changes at all levels from molecules to morphology. Now said, let us move on.

The shrinking of the grey matter is frequently reported to stem from neuronal cell death. Our primary focus on multiplying new neurons that drop off with time, keeping the mind and the body fit.

The splendour of the mind is precious; do not forget the heart.

“Men ought to know that from the brain and from the heart only arise our pleasures, joy, laughter and jests as well as our sorrows, pains, griefs, and tears.”

Hippocrates (460 BC- 375 BC)

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* A version of this article appears in print in the 5 September, 2024 edition of Al-Ahram Weekly