Something incredible has happened to the human brain, according to Jeremy M. DeSilva, a Dartmouth College anthropologist, and three colleagues in research published in the October issue of the journal Frontiers in Ecology and Evolution:
“During the last 100,000 years, brain size remained steady in homo sapiens, until a rapid and dramatic change point only 3,000 years ago decreased human brain size at a rate 50 times greater than the previous increase during the Pleistocene period [from 2.6 million years to 11,700 years ago].”
Brain size in humans today averages 100 to 150 cubic centimeters smaller than it was in around 1,000 BCE, the scientists show. A brilliant piece by Haaretz science writer Ruth Schuster alerted me to this surprising finding.
How do these scholars know, for instance, that the brain of King Solomon, who died in 982 BCE after a 40-year reign, was bigger than mine by the size of a lemon? It makes perfect sense: Solomon was the wisest of men. But how do they know this? And why did our brains shrink anyway?
Turns out the answers lie partly with ants. Bear with me, it will all become clear.
Our Shrinking Brains
The human brain is an astonishing organ. It weighs only 1,300-1,400 grams, or about three pounds, less than 1/40th of our body weight, yet consumes 20% of our energy. This is why, when I am tired, hungry and lack energy, I feel dumb.
Our brains have 86 billion neurons. They transmit information to and from different parts of the brain using electrical and chemical signals, and to all parts of the nervous system. Of our body’s 20,000 protein-specific genes, some 400 are specific to the brain.
For decades, scientists have measured cranial volumes using human skulls. This is the volume of our brain matter. The volume is around 1,260 cc’s in men and 1,130 cc’s in women (about a quart and a cup) simply because men are physically bigger, on average.
It is not hard to compare the volume of a skull from 1,000 BCE to that of one today. Data show cranial volume has fallen by 10% over the past 3,000 years. Our brains shrank.
And here is the reason, according to DeSilva et al:
“… the recent decrease in brain size may… result from the externalization of knowledge and advantages of group-level decision-making due in part to the advent of social systems of distributed cognition and the storage and sharing of information.”
Let me translate: by 1,000 BCE, there were over 100,000 inhabitants each in Babylon, Mesopotamia; Memphis and Rameses in Egypt; and in several Chinese cities. Humans began living together in ever-larger social groups. This led to specialization. No single individual needed to know all the survival skills. In a city of 100,000, you can always find someone who knows what you seek.
Commerce evolved. Knowledge was exchanged, and services were traded. This is what DeSilva calls “externalization of knowledge.” Rather than store all vital knowledge in one brain, some of it could be stored in other brains and called upon when needed – provided human society was peaceful and collaborative.
And there may have been a tipping point – an agglomeration of people big enough so that knowledge became highly specialized, and collective intelligence replaced individual intelligence as a tool for survival and reproduction. Humans were smarter in large groups than alone or in small ones. They had collective IQ.
In terms of evolution, smaller efficient brains consumed less energy, and thus made those who had them better able to prevail and endure. Natural selection was at work.
But DeSilva has another theory: humans “self-domesticated.” To preserve harmony, human society “deliberately removed highly aggressive individuals from breeding populations, leading to a reduction in intra-population aggression… Brain reduction in this case would be a by-product.” Presumably, those murderous thugs kicked out of town had big ugly brain centers not wanted or needed.
Consider, for instance, our pet dog Pixie, a mixed-breed Yorkie descended from wolves. (All modern dogs are direct descendants of wolves). All the ‘wolf aggression’ in her brain has long gone generations ago. She greets all visitors with total happy exuberance. A tiny bit of wolf-aggression emerges only when the neighborhood cat strolls by insolently. She has self-domesticated.
Now, according to DeSilva, what do ants have to do with it?
Ants are incredible. Their brains are huge – fully 1/7 their body weight. “The computational power of an ant brain is remarkable for its size and miniaturization,” DeSilva notes. Ants and termites are perhaps the only living things whose social development parallels our own human society.
“Group-level cognition may select for reduced brain size and/or adaptive brain size variation”, conclude DeSilva et al. “Complexity in eusocial (i.e. highly social) insect colony organization may involve selection for… smaller neurally differentiated worker brains.”
Translation: when you are part of a smart collaborative group, your brain can be less smart, hence smaller, and more specialized. And natural selection will then give an advantage.
Some leaf-cutter ants cut the leaves. Others chew them up and make the food. Still others care for and feed the larvae. The queen has babies – c’est tout. Each ant brain is small and specialized, because it can be, when the whole ant colony self-organizes and specializes, like a big human city. And incidentally, there are a quadrillion (million billion) ants alive today, across 12,000 species. Whatever ant colonies do, it is working very well.
AND NOW, a peek into the future. Is there lemonade in that lemon-size shrinkage of our brains?
According to a US National Academy of Sciences study, “natural selection is still influencing the evolution of a wide variety of human traits, from when people start having children to their body mass index.” Evolution is still at work among humans.
Let’s think about what this means, if it is true – if nature is still selecting humans for the adaptability and suitability of our brains to our environment.
In the future, our frontal cortex – the part of the brain that generates creative ideas – will expand. But our neocortex, amygdala and hippocampus, where information is stored, should shrink, because they are becoming superfluous.
With a 128-gigabyte thumb drive (disk on key, invented by an Israeli, Dov Moran) that costs under $20, technology and silicon now can store, 2.4 million pages, 82,000 photographs or 40,000 minutes of video. Silicon replaces brain memory.
I still have shelves full of books, but rarely use them. Why bother, when search engines can complete your search request even before you finish typing a keyword sentence?
Machines can and do perform repetitive routine tasks. They pick and place products from warehouse shelves, assemble car fenders and doors, and lately, deliver packages. Brains will no longer need to do these tasks. Humanity can rid itself of those boring stultifying tasks we once had to do daily to make a living. The modern version of Henry Ford’s 1909 assembly line is now largely manned by robots.
Our future brains will not need to think conventionally. Artificial intelligence will do this better. Machine learning – algorithms that mimic how humans learn but faster and better – is becoming more efficient, perhaps more intelligent, than human learning.
According to the Darwin theory of survival of the fittest, large parts of our brains no longer create value for humanity and have become superfluous. Other, smaller parts have become crucial – the parts that imagine things that do not exist yet and create amazing innovations that reduce global warming, cure illness, amuse and entertain, educate, or enlighten. Those parts should expand.
Raymond Kurzweil is an American inventor who pioneered optical character recognition and revolutionary new music synthesizers. He predicted that computers and software would have human-level intelligence by 2030. That’s only nine years away. That may well happen sooner. And after that, he said, computers will leave us far behind.
Why? Simple. Human brains are limited by biology. And natural selection is very slow. Even the ‘rapid’ change in our brains since the year 1,000 BCE took 120 generations.
Humans take 18 years from birth to mature. Computers take just a few months or even less between generations. Computers advance and improve at light-speed; an IBM computer, Deep Blue, defeated world chess champ Gary Kasparov 24 years ago. Computers have infinite knowledge (access to all the knowledge ever created in history), can multitask with ease, remember everything that ever happened, and unlike me, never forget anything.
Frankly, I am not that worried about computers outsmarting us. I am worried about why collective intelligence, once the lifeblood of civilization and progress, is failing human society.
Innovation drives human progress. And innovation, in turn, is driven by teamwork – by groups that are smarter than the sum of their members. All businesses know this. It is the foundation of start-up success. We have known and understood this for decades – and nowhere more than in Israel.
Why, then, is collective intelligence failing us, in the one key arena where we need it most – democracy? Why are democratically elected bodies, including our Knesset, proving moribund, fractious, combative, rowdy and profane, as in the budget debate? Why are people everywhere choosing incompetent leaders?
Why have there been so many political stumbles in managing the pandemic and controlling global warming? Where is that social teamwork that ants have perfected, but humans seem to have forgotten, that enabled us to shrink our brains and rely on one another? Why do the most aggressive self-seeking brains seem to cluster among those we elect to lead us, driving our youth into deep pessimism? And why does our youth shun politics as if it were leprosy – just when the climate crisis crucially demands a high-level global collective IQ?
We must deal at once, not with ever-smarter computers, but ever-dumber politics, before it is too late. Political intelligence must not remain an oxymoron.
And the 2021-2022 government budget is a fine place to start.
The Budget
“The 2022 budget is an outstanding one… an unprecedented Arrangements Law… contains 27 reforms… if executed as proposed, these 27 reforms will change the direction of the economy and drive it forward.”
These are the lead sentences in Haaretz’s editorial on November 4. It is pretty rare for Haaretz to label any political process ‘outstanding.’ Their words contrast sharply with the verbal mayhem with which the opposition, led by Benjamin Netanyahu, blasted the Knesset in the budget debate.
At Netanyahu’s command, opposition MK’s boycotted meetings of Knesset committees for months – not unlike small children leaving a game of dodge ball because they are losing.
The Knesset narrowly approved the 2021 state budget early on the morning of November 4 with 61 in favor and 59 opposed, following a marathon overnight session. The opposition desperately sought a single defector from among the government MKs, and offered the moon, but failed to find one. A tie vote, 60-60, would have meant defeat for the budget.
Then at 3 a.m. early Friday morning on November 5, after another marathon session, the 2022 budget was passed in the third reading, 59-56, and bleary-eyed MKs headed home to sleep.
“Why are we only passing a budget after three and a half years?” Prime Minister Naftali Bennett asked rhetorically. Ask Netanyahu.
Recall how Netanyahu and then-finance minister Israel Katz strangled the budget process for years, purely to prevent Benny Gantz from succeeding Netanyahu according to a coalition agreement. Lack of a budget automatically disperses the Knesset and leads to an election. The Knesset last passed a state budget in March 2018 – 1,334 days without a new budget! The cost to our economy was high and superfluous.
United Torah Judaism MK Yaakov Litzman, former Health and Construction minister and now in opposition, referred to the budget provision providing funds to neuter street cats. “First time dogs give money to cats,” he said.
Dogs? Presumably, the government and its ministers. Is it dawning on Litzman and the haredi parties that they no longer have a direct unlimited pipeline into the public coffers, nor will they for years to come? Technically, an election need not occur until March 2023, now that a two-year budget has been approved. Another futile, deadlocked election has been prevented.
The budget passed by the Knesset for 2021 amounts to NIS 609 billion ($194 billion), and NIS 573 billion ($183 billion) for 2022. The government decided to present a two-year budget for fiscal years 2021 and 2022.
The budget deficit will be 5.5% of Gross Domestic Product in 2021 and 3.9% in 2022, well below that of the US. The deficit has been halved from 2020, when it was 11.6% of GDP, driven by spending related to corona.
The biggest increase will go to the Transportation Ministry, led by Labor Party head Merav Michaeli: a 21% rise, in the face of snarled traffic that is getting worse daily.
The ratio of public debt to GDP will remain stable, at a reasonable 73%, far below the US level of 128%. Interest payments on the debt swallow NIS 41 b. ($12.7 b.), but have risen only by 3% as world interest rates remain low.
Divine Providence has smiled on the Bennett cabinet. The hi-tech stock index NASDAQ more than doubled between March 2020 and the end of October 2021.
In a booming stock market, Israeli hi-tech companies have taken the opportunity to raise cash and list their shares. The resulting profits proved to be an enormous windfall to Israel’s tax coffers: 65 billion shekels ($20 billion) in 2021, which helped moderate the deficit. This windfall eliminated the need for austerity spending cuts and tax increases, making the budget far more amenable to ordinary folks’ needs and far easier to pass.
We the people are winners. The big loser is opposition leader Benjamin Netanyahu. Passing a budget vaccinates the ruling coalition against the automatic dissolution of the Knesset and resulting call for an election. Netanyahu is now doomed to years in opposition, while his trial proceeds. The recent bitter Knesset exchange between him and Bennett reflects his deep frustration at failing to regain power – by just a single MKs raised hand.
The writer heads the Zvi Griliches Research Data Center at S. Neaman Institute, Technion, and blogs at www.timnovate.wordpress.com