The Evolution of the Brain — Part II
Or, our brain isn’t necessarily more evolved than others
👋 Hey there! My name is Abhishek. Welcome to a new edition of The Sunday Wisdom! This is the best way to learn new things with the least amount of effort.
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Alright! On to this week’s essay.
What if I told you that the size of our cerebral cortex doesn’t determine our rationality? What if I told you that what really matters is proportional size? What if told you that we need a better definition for rational behaviour since emotions are rational as well?
This is the second part of a two-part essay on the evolution of the brain. It’s about 1,500 words.
Q: What is rational behaviour anyway?
Let’s start right where we left off in the last essay: Does brain size matter? Or, more precisely, does our unusually large cerebral cortex make us super rational beings who can invent capitalism and engage in endless philosophical discourse about the meaning of life?
Well, yes, our cortex is big and has grown over time, giving us some cognitive advantages. But the more important question is whether our cerebral cortex has grown disproportionately compared to the rest of our brain. So, instead of asking if our cerebral cortex is big, it’s better to ask if it’s big in relation to our overall brain size.
Here’s a relatable analogy. Think about kitchens. Some are spacious, while others are tiny. If you walk into a huge kitchen, you might assume the people who live there love to cook.
But hold on! You need to consider the kitchen in relation to the rest of the house. A big kitchen in a big house is normal — it’s just a scaled-up version of a regular kitchen. But if you find a massive kitchen in a tiny house, chances are the occupants are gourmet chefs or something.
The same goes for brains. If a brain has a proportionally large cerebral cortex, it’s not really extraordinary. That’s exactly what humans have! All mammals have a relatively big cortex in a relatively big brain compared to their body size. Our cortex is just a bigger version of the cortex found in smaller-brained primates, like monkeys and chimpanzees, and many carnivores. And it’s a downsized version of the cortex found in the bigger brains of elephants and whales.
If a monkey’s brain grew to be the size of a human brain, its cerebral cortex would be the same size as ours. Elephants have a much larger cerebral cortex than we do, but that’s because they’re, well, elephant-sized!
So, the size of our cerebral cortex isn’t a new thing in evolution, and it doesn’t need any special explanation. And here’s the kicker: its size doesn’t determine how rational a species is. That whole idea of a big, rational cortex has been floating around for years, but it’s just a myth.
What basically happened was that evolution played with different genes and made certain brain development stages last for different durations, resulting in brains with proportionally bigger or smaller components.
Any info that claims the neocortex, cerebral cortex, or prefrontal cortex is solely responsible for rationality, or suggests that the frontal lobe controls emotions to keep irrational behaviour in check, is either outdated or incomplete.
Now, it doesn’t mean that having a bigger brain doesn’t have it’s advantages. It’s true that we’re the only animal that can build skyscrapers and invent airplanes. But then there are animals who have evolved abilities that surpass ours in significant ways.
For example, we don’t have wings to fly. We can’t lift fifty times our own weight. We can’t regrow amputated body parts. Such abilities are superhero powers to us but business as usual for allegedly “lesser” creatures. Even bacteria are more talented than we are at certain tasks, like surviving in harsh, unfamiliar environments such as outer space or the insides of your intestines.
What I’m trying to say is basically this. Other animals are not inferior to humans. They are uniquely and effectively adapted to their environments. In other words, our brain is not more evolved than a rat or lizard brain; it’s just differently evolved.
But, if the triune brain is really a myth, why is it still so popular? Why do college textbooks still depict a limbic system in the human brain and say it’s regulated by the cerebral cortex? Why do expensive executive-training courses teach CEOs to get a grip on their reptilian brains if experts in brain evolution dismissed such ideas decades ago? Partly it’s because those “experts” don’t read books, but mostly because the triune brain is a story that comes with its own cheering section.
With our unique capacity for rational thought, the story goes, we triumphed over our animal nature and now rule the planet. To believe in the triune brain is to award ourselves a first prize trophy for Best Species.
The war of rationality versus emotion and instinct has long been our best explanation for our behaviour. If we restrain our instincts and emotions appropriately, then our behaviour is said to be rational and responsible. If we choose not to act rationally, then our behaviour may be called immoral, and if we’re unable to act rationally, we are considered mentally ill.
This brings me to the central question of this essay: What is rational behaviour? Who defines that?
Well, traditionally, people thought being rational meant being emotionless. Like, thinking was considered rational, while feeling emotions was seen as irrational.
But hold on a sec, that’s not always true. Sometimes emotions can be totally rational. For example, if you’re scared because there’s a real danger, that fear is a rational response. And sometimes our thinking can be pretty irrational, like when we waste hours scrolling through social media thinking something important will magically pop up.
So, maybe we should define rationality in a different way. Let’s think about the brain’s important job: managing our body’s resources, like water, salt, and glucose. From this perspective, being rational means using or saving these resources in a way that helps us succeed in our immediate environment.
Picture this: you’re in a dangerous situation, and your brain gets you ready to run like crazy. It tells your adrenal glands to release cortisol (often referred to as the “stress hormone” because it is released in response to stress), which gives you a burst of energy. From the old view of the brain, this cortisol rush is just an instinct, not rational. But if we look at it from a resource management standpoint, it’s actually rational. Your brain is investing in your survival (and the future of your potential offspring).
Now, imagine if your body gets ready to run even when there’s no danger. Would that be irrational behaviour? Well, it depends on the situation. Let’s say you’re a soldier in a war zone where threats are all around. It’s reasonable for your brain to predict danger often. Sure, it might make mistakes and flood you with cortisol when there’s no real threat. You could see this as wasting resources and being irrational. But in a war zone, it could actually be rational from a resource management perspective. You might use up some glucose in the moment, but in the long run, you increase your chances of survival.
Now, let’s say you come back home from war to a safer environment, but your brain still keeps triggering false alarms, like in post-traumatic stress disorder. Even that behaviour could be considered rational. Your brain is trying to protect you from what it believes are threats, even though it’s depleting your resources with all those frequent alarms.
The problem is that your brain’s beliefs don’t match your new environment, and it hasn’t adjusted yet. So, what we call mental illnesses might actually be short-term rational resource management that’s not in sync with the immediate situation, the needs of others, or your long-term best interests.
So, being rational means making a smart resource management investment in a given situation. When you exercise hard and feel that surge of cortisol in your body, it might not feel pleasant, but it’s rational because it’s good for your future health. Even when you receive criticism from a boss and your cortisol levels rise, that can be rational too because it helps your brain access more glucose to learn and improve.
These ideas, if we take them seriously, could seriously shake up some of our cherished belief systems. Take the law, for example. Lawyers often argue that their clients’ “emotions took over their reason in the heat of the moment,” so they’re not fully responsible for their actions. But feeling distressed doesn’t mean you’re being irrational or that your emotional brain has taken over your supposed rational brain. That distress could be a sign that your whole brain is using resources to achieve a future benefit.
There are plenty of other social institutions built on the idea of a battle between different parts of the mind. In economics, for instance, they assume there’s a clear divide between rationality and emotions when it comes to investor behaviour. In politics, we see leaders with conflicts of interest who believe they can put aside their emotions and make rational decisions for the greater good. But underneath all these ideas lies the myth of the triune brain.
So the bottom line in this. You don’t have an inner reptilian or a wild beast-brain. There’s no limbic system exclusively for emotions. The so-called neocortex isn’t a fancy new feature either. Many other vertebrates have similar neurons that, in some animals, come together to form a cerebral cortex if the right stages persist long enough.
I rest my case!
Today I Learned
The Anglo-Zanzibar War of 1896 was over quicker than it takes me to stumble out of bed in the morning. Talk about a brief but memorable conflict! If you’re wondering how on earth a war can be condensed into a mere 38 minutes, read along.
So, in the late 19th century, Britain was busy extending its influence over East Africa, including the lovely island of Zanzibar. The British were all about spreading their colonial wings, and Zanzibar found itself caught in the middle of their grand plans.
See, Zanzibar had a long history of trade and importance, thanks to the efforts of Sayyid Saʿīd ibn Sulṭān, who put the island on the map. But his successor, Barghash, had a tougher time dealing with the European powers.
By 1890, Britain had persuaded Zanzibar to hand over its mainland territories to Germany, while keeping the island itself as a British protectorate (which is just a fancy way of saying “colony”). The British promised to let the sultanate continue existing, but they made it clear that the sultan’s power was about as real as a unicorn.
Once they took charge, the British had two main goals in mind: abolish slavery and revive Zanzibar’s mercantile economy. Not a bad agenda for a coloniser, I must say. However, the Zanzibari merchants weren’t exactly thrilled with the new policies, especially the one about ending slavery. I mean, come on, slavery was their bread and butter, or should I say, spice and curry?
Now, when it came to choosing the next sultan after the death of Barghash, the British threw their support behind Ḥamad ibn Thuwayn. But hold on tight, because the defiant Prince Khālid ibn Barghash (the son of the original Barghash) had other plans.
Barghash Jr. stormed into the palace, claiming that he, as the only son of the late Barghash, should rightfully be the ruler. Never mind that Zanzibari succession laws didn’t really care for the whole hereditary thing. The British managed to convince Barghash Jr. to back down, and Ḥamad became the uncontested sultan.
However, Ḥamad’s initial cooperation with the British soon turned sour. By 1896, he was feeling pretty resentful towards his British overlords. He even formed a 1,000-man military force loyal only to him. Talk about a sultan with trust issues! Then, on one fateful day in August, Ḥamad passed away, sparking yet another succession struggle.
The British had their new candidate, Ḥamud ibn Moḥammed (this time it’s Ḥamud instead of Ḥamad), all ready to take the throne. They thought he’d be the perfect malleable sultan who wouldn’t put up a fight against the abolition of slavery.
But Barghash Jr., who had already been passed over, wasn’t about to be sidelined again. He declared himself the sultan of Zanzibar, seized the palace, and even surrounded it with 3,000 soldiers and supporters. He meant business this time.
But guess what? The British weren’t about to let some upstart prince ruin their day. Rear Admiral Harry Rawson sent Barghash Jr. an ultimatum, demanding that he and his troops surrender by 9:00 am or face the wrath of British firepower.
Now, you’d think Barghash Jr. would have taken this seriously, but nope! He believed the British wouldn’t follow through on their threat. Oh boy, was he in for a surprise!
At the strike of 9:00 am, British warships opened fire on the palace. Boom! Flames engulfed the building in no time. The Glasgow, the armed royal yacht that supported Barghash Jr., tried to retaliate by firing on the British ship St. George, but Rear Admiral Rawson swiftly took care of the pesky yacht.
Within 38 minutes, the British had inflicted 500 casualties on Barghash Jr.’s forces, with only one British sailor getting a serious boo-boo. Talk about efficiency!
With the palace in ruins and Barghash Jr. realising he might have underestimated the British resolve, he sought refuge in the German consulate. Meanwhile, Ḥamud ibn Moḥammed (the Brit’s original candidate) was promptly named the sultan of Zanzibar, and he wasted no time in accepting all the British terms, including the abolition of slavery. Wise choice, if you ask me.
As for Barghash Jr., the Germans graciously allowed him to live in exile on the mainland. He stayed put until the British nabbed him during World War I. The poor guy eventually met his end in Mombasa in 1927.
And that was how Zanzibar learned not to mess with the British Empire’s military might. After enduring that 38-minute firework show, the island remained relatively quiet until 1963 when Britain finally released it from its protectorate status.
The joys of British colonial history! It’s like a rollercoaster ride, except instead of thrills, you get tea on battleships.
Interesting Finds
Consciousness is a complex phenomenon that is still not fully understood by scientists. There is no single definition of consciousness, but it is generally understood to be the state of being aware of oneself and one’s surroundings. Consciousness is thought to be the result of a complex interplay of neural processes, but the exact mechanisms are still unknown. There is evidence that consciousness may be shared between humans and other animals, but the extent of this sharing is still unclear. The possibility of artificial consciousness is a topic of ongoing debate. Some scientists believe that it is possible to create artificial consciousness, while others believe that it is not.
Matthew Desmond’s book Poverty, by America explores poverty statistics, the lived experiences of the poor, and the exploitation of the masses by America’s wealthy. He argues that the country’s employers, financial institutions, and landlords extract money from low-income families while hoarding opportunities for themselves. Desmond emphasises that America’s safety-net programs are insufficient and poorly designed. He highlights the high child-poverty rate in the US compared to peer countries and attributes it to the country’s tolerance for poverty. Desmond also underscores the role of racism in perpetuating poverty and calls for policy solutions such as expanding housing vouchers, implementing rent control, and addressing banking fees. He points out that robust government spending during the COVID pandemic had a significant positive impact on poverty rates but expresses concern that these gains may be reversed without continued support.
The Honeymooners, a popular American television comedy from the 1950s, revolves around the daily lives of working-class characters who heavily rely on public transportation in New York City. This highlights the significant role public transit played in the working-class lifestyle of the era. However, during the same period, the car symbolised freedom and rebellion for the beatniks and hipsters. Today, the perception has flipped, with public transit being championed by reformers, and cars seen as a symbol of consumerism and inequality. Two new books Carmageddon and Paved Paradise critique cars as agents of social oppression, inequality, and ecological disaster, advocating for alternatives like rapid transit and bicycles. The history of transportation reveals its impact on society and the moralising nature of transportation debates.
Timeless Insight
Imagine this scenario: you’re sitting in your workplace, and someone asks you: “If you were financially independent, let’s say you had $1 million, would you still choose to work here?”
Now, you might think that this is a loyalty test and that the answer should be a resounding “yes.” But here’s the twist: most genuinely smart people respond with, “Yes, I would still work here, but I wouldn’t want to do X, Y, or Z anymore.”
Now, what are these mysterious X, Y, and Z tasks? Well, they tend to be the repetitive, mundane, and downright boring tasks that no one really enjoys doing. You know the ones I’m talking about — data entry, formatting, documenting, calculating, reporting, modelling, invoicing, testing — the list goes on.
They’re the mind-numbing, rules-based tasks that don’t require much creativity. And here’s the thing: these are the very tasks that businesses should be looking to automate and streamline in their daily work.
Here’s the secret behind this question: it’s not about testing someone’s loyalty or making them feel bad about their job. No, no, no! It’s about uncovering the inefficiencies in their role. This question is more for the employer and less about the employee.
By identifying those tasks that can be automated, a business can free up time and energy for the more engaging, creative work — the kind of work that constantly challenges people to think in new ways and explore uncharted territories.
You see, when businesses remove those monotonous tasks from people’s plate, what’s left is the exciting stuff — the work that ignites passion and keeps people fully engaged. It’s the kind of work that you might even enjoy doing without a paycheck.
Take this question as an opportunity to reflect on your job, identify the tasks that drain your spirit, and explore ways to automate or delegate them. Embrace the creative and stimulating work that truly fulfils you, and who knows? You might find yourself eager to jump out of bed every morning, even if you had all the financial independence in the world.
What I’m Reading
The self is not an immutable entity that lurks behind the windows of the eyes, looking out into the world and controlling the body as a pilot controls a plane. The experience of being me, or of being you, is a perception itself — or better, a collection of perceptions – a tightly woven bundle of neurally encoded predictions geared towards keeping your body alive. And this, I believe, is all we need to be, to be who we are.
— Anil Seth, Being You: A New Science of Consciousness
Tiny Thought
History is driven by surprising events but forecasting is driven by obvious ones.
Before You Go…
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I’ll see you next Sunday,
Abhishek 👋
PS: All typos are intentional and I take no responsibility whatsoever! 😬