Chapter 27: From Sociobiology to Human Society

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Welcome back to The Deep Dive.

Today, we are tackling something.

Well, it's a truly massive intellectual endeavor.

Our mission is to try and understand human social behavior by treating homo sapiens as, you know, a single very peculiar primate species.

That's right.

We're diving into the final and I think most ambitious chapter of E .O.

Wilson's sociobiology.

The chapter is called Man From Sociobiology to Sociology.

And the goal here is to view the humanities and social sciences not as these separate fields, but really as specialized branches of biology.

I love that framing, that macroscopic view.

It's like imagine you're a zoologist from another planet cataloging life on earth, suddenly history, biography, even fiction.

It all just becomes research data on human ethology.

Exactly.

And the central task, as Wilson lays it out, is this search for what he calls the human biogram, that fundamental set of inherited behaviors and rules that makes us who we are.

And the core argument is so important to get right from the start.

He's asking how much of our modern life is a real adaptation to culture versus how much is just a leftover, a phylogenetic vestige.

And he says our civilizations with all their complexity and contradictions are jerry -built around this biogram.

There are these improvised structures built on a very old inherited foundation.

Okay, let's start there.

Let's unpack that peculiar primate.

What makes homo sapiens so ecologically different from, you know, every other ape or monkey out there?

Well, it starts with the simple facts of where we live and how many of us there are.

We're easily the most successful primate, ecologically speaking.

We occupy the widest geographical range and have the highest local densities of any species in our order.

And we're the only ones left.

That's a huge point.

We preempted every other similar hominid niche.

In the past, you had Australopithecus and early home coexisting, not anymore.

Now it's just us.

We're the sole inheritors of that entire lineage.

And the physical machine that allowed for that global dominance, it required a total redesign, especially for bipedalism.

I mean, walking on two legs is one thing, but they're built for it.

Oh, completely.

The anatomical changes are profound.

Every part of the skeleton got reshaped for that erect posture.

Your spine, for example, it developed those S -curves to distribute weight and act as a shock absorber.

And our chests are flat compared to other apes.

Right, which was critical for moving our center of gravity closer to the spine.

It stops us from constantly falling forward when we walk.

Okay.

And then there's the pelvis.

In most primates, it's pretty narrow, but ours became this

piece of architecture.

A massive piece of architecture.

It broadened out for two

simultaneous critical jobs.

First, it gave a huge surface for those powerful leg muscles you need for striding.

Second, it reshaped itself into a kind of basin.

A basin?

To physically hold your

viscera?

It's a necessary adaptation for standing upright.

Even the cossackics, the remnant of our tail, curved inward to lock into that pelvic floor.

So it's a total reorientation from the bottom up.

What about the head?

Same story.

The occipital condyles, the joints where your skull sits on your spine, they rotated way underneath the head.

In a chimp, they're toward the back.

In us, they're central.

It lets that big, heavy head balance perfectly with minimal muscle effort.

The feet, of course.

The feet completely lost their grasping ability.

They became narrow and long, designed purely for pushing off the ground.

It's a total evolutionary commitment to walking and running.

Okay, so that's the skeleton.

But moving to the outside, we have the whole naked ape puzzle.

Why on earth did we lose all our body hair?

The most plausible idea ties right back into all those anatomical changes.

It's about thermoregulation.

About keeping cool during strenuous activity.

With sweating.

Exactly.

Nakedness allowed the body to cool down through an incredible reliance on sweating.

We have between 2 and 5 million sweat glands.

That's way more than any other primate.

And it would have been a massive advantage out on the African plains in the middle of the day.

So we basically traded raw speed for endurance.

We can't outrun a gazelle in a sprint.

But we can literally run it to exhaustion.

That cooling system gave early humans a decisive advantage in what's called persistence hunting.

In the heat, other animals overheat pretty quickly.

We can just keep going for hours.

That one adaptation seems to have shaped our entire hunting strategy and diet.

So next, the source talks about a revolution in our reproductive lives.

Specifically, the female estrus cycle.

Right.

There are two huge shifts here.

First is the intensification of menstruation.

I mean, some other primates have slight uterine bleeding, but only human women have that heavy, regular sloughing of the uterine wall.

And the second, which is probably more important socially.

Is the loss of estrus.

That clear cyclical period of female heat was replaced by continuous sexual activity and attractiveness.

The reproductive cycle was essentially flattened out.

That's a massive departure from almost every other mammal.

What was the evolutionary advantage of losing that clear signal?

It was about cementing what he calls close marriage bonds, basic to human social life.

Unlike most animals, where the bond might only last long enough for conception, our sexual interests became detached from just fertilization.

Which means you need permanent signals of sexual availability.

Exactly.

This required the evolution of fixed sexual attractants, pubic hair, the protuberant breasts and buttocks of women.

They advertise sexual maturity all the time, not just during a fertile window.

And that helps cement the bonds needed to raise our very slow maturing, very dependent children.

So the shift from cyclical to continuous sex was fundamentally about making that pair bond more permanent.

To ensure parental investment.

That's the synthesis, yes.

It enabled the division of labor and mutual protection that was so necessary for raising a family on the savanna.

Okay, now for the ultimate human specialization.

The brain.

The book calls it mental hypertrophy.

I mean, can you just describe the sheer scale of this expansion?

It was an explosion.

There's a graph showing cranial capacity over the last three million years, and the curve just goes almost straight up.

Around three million years ago, Australopithecus had a brain of about 400 to 500 cubic centimeters.

Which is like a modern chimp or gorilla.

Right.

And then, in what is really just a blink of an eye evolutionarily, it doubles.

Two million years later, Homo erectus hits about a thousand cubic centimeters.

And it didn't stop there.

Neanderthals and modern homo sapiens range from 900 up to 2000 cubic centimeters.

That is mental hypertrophy.

The book says this growth didn't just enhance our basic primate social qualities, it violently distorted them.

What does that mean in practice?

It means that a basic primate trait, like say a plastic social organization, got warped into something like protein ethnicity.

These complex shifting identities.

Rudimentary individual bonding ballooned into these vast institutional networks of reciprocal altruism.

So our intelligence took these basic animal instincts and just amplified them into something almost unrecognizable.

Unpredictable, subtle, and endlessly complex.

And that distortion is what makes our societies so fascinating and so chaotic.

Tracing those distorted qualities back to their deep roots, to the biogram.

That's the whole project.

Which brings us to the next section on the incredible flexibility or plasticity of human social organization.

Right.

If you just look at the raw data group size, hierarchies, gene exchange rates, you find far more variation among human societies than you do among any other single primate species.

I mean, a zoologist from another planet would have a hard time believing that a Kung Bushman and a modern New Yorker are the same species.

And that social flexibility really starts at the level of the individual.

Absolutely.

Even in the simplest societies, you see huge individual differences.

You have leaders, you have entrepreneurs, you have specialists in ritual, and you have people who are just lifetime status acceptors and never challenge things.

This ability to adopt so many different roles is probably in itself highly adaptive.

It's really interesting to compare that to social insights.

They also have individual differences, right?

Some answer elite, some are sluggish, but the colony's behavior is always uniform.

That is the critical difference.

In insects, you have these very powerful, very precise, negative feedback loops.

If the colony needs more food, some workers just switch to foraging.

Any disruption is a disaster because the whole system is calibrated for uniformity.

But in humans...

In humans, the controls are much, much weaker.

Deviating from the norm is way less dangerous.

And this leads to one of the most interesting ideas in the chapter, pathological endurance.

The idea that deeply dysfunctional human societies can just persist for generations.

This is such a critical point.

We tend to assume that a broken system has to collapse.

But the anthropological record is full of counter examples.

Take the Hobbesian Slave Society in Jamaica.

It lasted for two centuries.

And it was completely pathological.

Utterly.

Systemic promiscuity, neglect of family structures, a legal system used just for control.

But the economy worked and the population grew.

The internal pathology didn't lead to immediate collapse or extinction.

Wow.

And then there's the even more extreme case of the Ike of Uganda.

A truly tragic case.

They were hunters forced into farming on terrible land.

And they were constantly on the brink of starvation.

Their entire culture was just reduced.

The only thing they valued was on gag or food.

The word for goodness just meant having a full stomach.

So all the things we think of as fundamentally human family and mutual care, they just dissolved.

They were gone.

Children were abandoned at age three.

The family unit disappeared.

Sex was minimal.

When someone died, it was a relief because it meant more food for the survivors.

But the society itself remained stable for over 30 years.

How is that possible?

Wilson's explanation is ecological release.

Humans have been so successful at dominating our environment that the intense pressure from other species, the pressure that punishes any efficiency is mostly gone.

So the insight isn't just that these societies are broken.

It's that we're so dominant that biology has stopped punishing us for being broken.

Almost any culture, no matter how pathological, can survive for a while as long as it allows for some reproduction.

That's the takeaway.

We have a huge margin for error that other animals just don't have.

And this inherent plasticity brings us right into the classic culture versus gene debate.

The standard environmentalist view from someone like Dobzhansky was that the capacity for culture is genetic, but the content of culture is not.

The idea was that our genes just surrendered their sovereignty to culture.

But the genetic counterpoint which Wilson is making is that this ignores the fact that the underlying behavioral traits that drive cultural variation are themselves heritable.

So we're not talking about a gene for specific custom, but heritable traits like dominance or introversion.

Precisely.

Things like introversion, extroversion, neuroticism, personal tempo.

These things show moderately high heritability.

The hypothesis is that even a small genetic difference in these traits between populations could predispose them toward different cultural paths that then get amplified over time.

So since we can't just look at the genes directly, we have to use indirect methods to figure out what the biogram looks like.

The first one involves looking for the elementary rules of human behavior.

Right.

And this leads to a fascinating reconciliation of two giants of social science, Abraham Maslow and George Homans.

Maslow gave us the hierarchy of needs.

Which is essentially an ordered set of goals.

You have to meet your basic needs first, hunger, sleep, then you move up to safety, then belonging, then esteem, and finally self -actualization.

And on the other side, you have Homans, the behaviorist, who reduced everything down to four simple rules based on associative learning and reward.

Exactly.

Homans is all about the how, the transactional mechanisms.

His rules are all about reinforcement.

If an activity was rewarded in the past, you're more likely to do it again.

The more often it's rewarded, the more you do it.

And the value of the reward matters.

Right.

More valuable rewards lead to more behavior.

But, and this is the key one, the more you get a reward, the less valuable it becomes.

Satiation.

Okay.

So Homans gives us the simple how and Maslow gives us the motivational why.

How does biology bring them together?

It's actually a really elegant synthesis.

Wilson suggests that Homans' simple rules are the enabling devices, the basic learning machinery through which the biogram expresses itself.

The word reward is just whatever our brains and motive centers have defined as desirable.

And Maslow's hierarchy is the instruction manual for what's desirable and in what order.

That's it, exactly.

The hierarchy provides the goals for Homans' mechanisms.

And in the end, what's desirable is measured in the ultimate currency of genetic fitness.

Those emotive centers have been programmed by natural selection to want safety, belonging, and reproductive success in that order.

That's a powerful way to ground psychology and biology.

Okay.

The second, more rigorous method is phylogenetic analysis.

This is about avoiding the trap of just picking one plausible story.

Right.

This is the serious method.

You classify traits by their evolutionary lability, how stable or changeable they are over deep time.

This lets us figure out which traits we can confidently trace from our primate ancestors to us.

So you have conservative traits and labile traits.

What are some of the conservative ones?

Conservative traits are the ones that are constant across most primates.

So they're likely to be part of our deep biogram.

These include things like aggressive dominance systems, with males usually on top, prolonged maternal care, and a tendency toward matrilineal social organization.

And the labile traits, the ones that change all the time.

These are things like group size, how cohesive the group is, how open it is to strangers, how much males are involved in parental care, and the specific form of territorial defense.

You can't safely extrapolate those from other primates to humans because they're so variable.

So what does that pattern tell us about the human biogram?

It shows that our conservative traits, like dominance and maternal care, are pretty consistent across human societies.

But the labile traits, like group size and territoriality,

are wildly variable among humans.

This suggests that the traits that were evolutionarily flexible in our ancestors are also the ones most likely to vary between human societies today.

Okay, let's pivot something that really separates us economically.

Barter and reciprocal altruism.

Our instinct for sharing is incredibly strong, on a level you only really see in social insects.

And it's very rare in other primates.

Chimps show glimmers of it, but that's about it.

And because of that strong sharing instinct,

humans are the only animal with a true economy.

And our intelligence allows us to stretch that sharing out over time, which is the basis for reciprocal altruism.

That is the profound shift.

It's not, I give you food, you give me food right now.

It's, I give you something today with the full expectation you'll repay me maybe months or years from now.

And money.

Money is just the ultimate quantification of that promise.

It's a universally recognized IOU, a pledge to surrender services or property at a later date.

And the earliest form of this was the exchange of meat from males for plant food from females, which created this powerful economic based sexual bond.

And that idea of exchange got extended even further into kinship and alliances, which leads to the controversial hypothesis of the barter of women.

The idea from Fox and Levi Strauss that women were essentially a form of social currency.

Exactly.

To cement alliances and build kinship networks.

By controlling who got which females, high status males could accumulate more power.

You see this in some Australian Aboriginal societies with these incredibly complex marriage rules where men would trade their nieces to form alliances.

It ensured that older powerful men gained both political and reproductive advantages.

And this practice of exogamy marrying outside the group has huge genetic consequences.

It really does.

It keeps different populations genetically similar.

Even a gene flow of just 10 % per generation is enough to stop two populations from diverging too much.

So exogamy, which likely evolved to prevent inbreeding, also had the effect of keeping the human species genetically unified.

But all of this complex social exchange relies on trust and constant negotiation.

Oh, absolutely.

Irving Goffman's work was all about this.

We're constantly probing each other, trying to figure out status, intelligence, and most of all, trustworthiness.

And we're doing this while the other person is actively trying to manage their own image.

So deception and hypocrisy aren't just moral failings.

They're what?

Functional tools.

He describes them as very human devices for conducting the complex daily business of social life.

Complete brutal honesty would probably destroy society beyond your immediate family.

In this world, good manners become a necessary substitute for true love.

That is a very stark way of looking at it.

Okay, let's focus on what he calls the fundamental unit of our species, the nuclear family.

It's the basic building block, a mother, father, and offspring living together.

You find it in virtually every known human society, from hunter -gatherer bands to modern cities.

Its universality is a core feature of our biology.

And the division of labor within that unit is also surprisingly consistent.

It is.

The general pattern is women and children in the residential area, and men foraging further afield for game, or today, it's equivalent money.

And this ties back to our unique sexuality.

The bonds are meant to be permanent, and polygamy is almost always a male practice.

Right.

And the continuous sexual behavior reinforces that permanent bond, which is vital for raising our kids.

The text makes a great point here that any religious natural law argument against non -procreative sex is just based on bad ethology, because our reproductive behavior is so different from other animals.

Beyond the family, we have these extensive kinship networks.

Which act as a kind of social insurance policy.

They bind alliances, they're a way for young people to emigrate without conflict, and most importantly, they're a homeostatic device for hard times.

You mean like a safety net?

Exactly.

The Dog Rib Indians in Canada, for example.

When famine hits one band, they rely on help from relatives in other bands.

Kinship is literally a survival mechanism written in our genes.

All this complexity means that humans are constantly switching roles, what's called polyethism.

Right.

And unlike insect casts, which are fixed and don't compete,

human role actors are always competing.

We're always trying for upward mobility, always vying for a bigger share of the rewards.

Which brings us back to the genetics.

If these roles and the traits for success are heritable, could you get genetic stratification?

It's theoretically possible.

Dahlberg's model showed that if you had a single success gene, and upward mobility was common, that gene could get concentrated in the upper classes in just a few generations.

And Heernstein famously argued that as society gets more equal, class differences would become more and more defined by genetic differences in things like intelligence.

That was his argument.

But the evidence suggests that this kind of hereditary solidification is pretty weak in most societies.

The Indian casts, for example, after 2000 years of strict separation, show only slight genetic differences.

So why doesn't it happen?

A few reasons.

Culture is fluid, there are many paths to success, and most importantly, success is highly polygenic.

It's not one gene.

It's a mix of IQ, creativity, drive, stamina.

And all those genes get scrambled every generation.

It keeps the system dynamic.

Speaking of inherited traits, we have to talk about the evolutionary puzzle of male homosexuality.

It is a major puzzle.

The data suggests around 10 % of males are predominantly homosexual.

Since that typically leads to fewer direct offspring, the question is, how does the trait persist?

What are the main hypotheses?

Well, one is heterozygote superiority, that the genes might confer some other fitness advantage when you only have one copy.

But the more sociobiologically interesting idea is kin selection.

The idea that you can pass on your genes by helping your relatives reproduce.

That's the one.

In primitive societies, homosexual members might have functioned as amazing helpers.

Freed from direct parental duties, they could devote their energy to helping their nieces and nephews survive and reproduce.

So the loss in direct fitness is made up for by the gain in inclusive fitness.

That's the theory.

The genes for homosexuality could be maintained in the population by boosting the reproductive success of the entire family.

It's a fascinating idea.

Let's switch gears to the biggest jump of all.

Language.

The quantum jump.

Our whole social world pivots on this unique system of communication.

But it's built on a surprisingly rich nonverbal foundation.

Our paralanguage, body posture, facial expressions is huge.

Maybe 150 to 200 distinct signals.

And some of those are really old.

Very old.

Smiling and laughing have direct homologues in other primates.

They are some of our most ancient universal signals.

But speech required major anatomical changes.

What had to happen in our throats for us to talk?

It was all about reshaping the resonator, the air tube.

Because we're upright, our mouth and pharynx meet at a 90 degree angle.

This pushed the tongue back and lengthened the pharyngeal space.

And what's the acoustic result of that?

It allows the tongue to make very subtle movements that dramatically change the shape of that cavity.

This is what lets us generate all the distinct phonemes, the E, A, and OO sounds that are the building blocks of speech.

But the real power of language isn't the sounds.

It's the syntax.

The grammar.

Right.

And figuring out the origin of grammar is a huge problem.

We can rule out the simplest model, the Markovian string, where one word just probabilistically leads to the next.

Why does that fail?

Because a child would have to learn an astronomical number of transitions.

Kids master grammar way too fast for it to be simple trial and error.

It suggests there's an underlying structure they're tapping into.

So that leaves us with the deep structure models.

The first being the learned deep structure model.

That one says the child learns a limited set of formal principles for combining phrases from their culture.

Language is a cognitive achievement that animals just aren't smart enough for.

But the favored model is the innate deep structure model from Noam Chomsky.

This is the idea that the principles of grammar are at least partially genetic.

They just emerge as the brain matures.

The implication is that deep structure might be universal across all human languages and that animals lack a specific inborn language faculty.

Can you break down how that structure works?

Well, you can think of it hierarchically.

A sentence like, the boy hit the ball, isn't just a string of words.

It's a noun phrase, the boy, plus a verb phrase, hit the ball.

These phrases are like modules you can swap in and out.

And then transformational grammar turns that deep structure into the sentences we actually say.

Exactly.

It uses rules to convert the underlying meaning into different surface forms, like turning a statement into a question.

The big unresolved question is whether those specific transformational rules are themselves innate or if they're learned.

Okay, let's move on to culture, ritual, and ethics.

People often say culture is proof that we've escaped biology.

But Wilson argues that while the details of culture are genetically underprescribed, the capacity for culture, the overwhelming tendency to create it is an evolved trait.

He uses that thought experiment from Robin Fox.

Right, if you could raise kids in isolation and they survived, they would eventually invent language, property rules, incest taboos, religion,

all the cultural universals.

They are the inevitable output of our biogram.

So culture is like an environmental tracking device running in parallel to our genes.

A hierarchical one.

Fast cultural changes are like fashion.

Slow ones are things like incest taboos.

The core hypothesis is that most cultural details are, in the end,

adaptive in a Darwinian sense.

They let us respond to environmental changes faster than genetic evolution can.

And the slowest, most formalized parts of culture are usually found in ritual and religion.

The earliest forms seem to be about magic actively trending to manipulate nature.

The cave paintings of animals with spears in them are likely sympathetic magic.

It's analogous to how animal intention movements get ritualized into signals.

And formal religion goes deeper, into creation myths and moral codes.

But the content is not universal at all.

For example, belief in a single active moral creator God isn't found in most hunter -gatherer societies.

That idea seems to arise most commonly when societies adopt a pastoral herding way of life.

The data on that is surprisingly strong.

It is.

There's a strong positive correlation between depending on herding and believing in that kind of high God.

The shepherd flock dynamic seems to really stimulate that kind of theology.

So if the doctrines are so contingent, why does religion endure even when parts of it are demonstrably false?

Because it's useful, not because it's true.

Rappaport argued that sacred rites are a massive communication tool.

They signal tribal strength, affirm moral values, and unite the group.

And they get rid of ambiguity.

Especially rites of passage.

The transition from child to adult is a slow, ambiguous biological process.

The ritual turns it into a sharp, arbitrary social dichotomy.

It clarifies everyone's status and responsibilities.

And the ultimate mechanism is sanctification.

Right.

To sanctify something is to declare it beyond question.

It serves the group's most vital interests and prepares people for supreme self -sacrifice.

God wills it is a potent mechanism for improving the summed Torwinian fitness of the tribe.

This willingness to conform brings us to the evolution of indoctrinability.

Wilson says we're absurdly easy to indoctrinate.

And that capacity is essential for group survival.

You can explain it through two pathways.

The group selection hypothesis says that cohesive conformist groups simply out -survive and out -compete groups of selfish individualists.

The genes for conformity spread because the groups that have them win.

And the individual selection path.

That argues that conformity primarily benefits the individual by letting them reap the rewards of group membership and avoid being ostracized.

The group then exploits that innate tendency, even for risky acts like warfare, because on average the winners get more resources and reproductive opportunities.

Both roads lead to the same destination.

A genetic predisposition for social conformity.

This takes us to the final, provocative step.

The biologization of ethics.

Wilson argues that ethics needs to be taken away from philosophers and grounded in evolutionary biology.

He critiques thinkers like Rawls for treating the brain as a black box and ignoring the fact that our genotype evolved under conditions of extreme unfairness and competition.

Is there any biological foundation for how we develop morals?

There is.

Lawrence Kohlberg's work mapped out sequential stages of ethical reasoning that are linked to mental maturation.

You move from a simple punishment and reward morality to a duty -based good boy morality.

And finally to a morality based on shared principles and conscience.

But that's still just a developmental map.

It doesn't explain the evolutionary why.

The sociobiological view is that our emotive centers, our gut reactions to moral problems, are the biological adaptations.

And moral conflict is innate because we have competing adaptations.

Group selection favors altruism while individual selection favors selfishness.

You're in a state of chronic moral ambivalence.

So a single universal moral code might actually be less adaptive than different codes for different ages and sexes.

That's the theory.

It might be adaptive for young children to be selfish to maximize resources while adolescents need to be sensitive to pure approval to form alliances.

Our moral programming might change over our lifespan.

Which means trying to apply one code to everyone is bound to create intractable dilemmas.

And that, Wilson says, is the current condition of mankind.

Okay, before we get to the final trajectory, a quick word on aesthetics.

The artistic impulse.

It's not uniquely human.

Chimpanzees will draw and paint in captivity.

They show a real drive to do it, and their art progresses through stages, just like in human children.

So the drive is linked to something practical, like tool use.

Yes.

For early humans, the ability to appraise form and skill in making a tool was a matter of life and death.

That appraisal brought social approval, which increased genetic fitness.

Art and music evolved from there.

Let's talk about territory.

How does that fit into the biogram?

If you define territory broadly, as an area occupied exclusively through defense or advertisement, then it's a general trait of hunter -gatherer societies.

And they had a dual system for it.

Right.

Exclusive use of rich gathering areas for the tribe or family, but overlapping shared hunting ranges.

This is ecologically efficient, given that a carnivore needs about 10 times the area of an herbivore.

The book mentions an insight from Hans Kummer about our intergroup responses being inadequate for the modern world.

Kummer's point was that our ways of dealing with other groups are still crude and primitive aggression, posturing.

But our ways of dealing with people within our group are incredibly complex and subtle.

Our ancient tribal toolkit is just not equipped for global civilization.

Which leads right to Garrett Hardin's definition of modern tribalism.

Which is any self -perceived group that follows a double standard of morality.

One set of rules for the in -group and another less charitable one for the out -group.

This directly generates xenophobia, resource hoarding, and the constant risk of war.

So let's wrap this up by looking at the trajectory of human social evolution.

It's defined by two big accelerations.

Stage one was the slow, multi -million -year transition from an arboreal primate to Australopithecus.

The big drivers were the move to the savanna and an increased dependence on meat.

And stage two was the rapid phase, starting about 100 ,000 years ago.

That was mostly cultural evolution built on top of the genetic potential that was already in place.

And the engine for all of this was the autocatalysis model.

A positive feedback loop.

Let's walk through that loop one more time because it's so central.

Okay, so bipedalism frees the hands.

Free hands lead to better tool use.

Better tool use puts a selective pressure on intelligence.

Higher intelligence leads to even better tools and cooperative hunting.

Better hunting provides more protein, which fuels a bigger brain.

And the cycle starts over, faster and faster.

And the shift to hunting big game was the major accelerator.

It seems to be.

But autocatalysis alone wasn't enough to get us all the way to civilization.

There were other prime movers.

Such as?

Sexual selection, for one.

With polygyny being common, there was a huge premium on male traits linked to success, hunting skill, leadership, social intelligence.

This created another feedback loop for advanced social traits.

And then there's the darker one, warfare and group selection.

It's inescapable.

Warfare has been endemic.

Darwin's model was brutal but probably accurate.

Better organized tribes supplant others.

The genes for cooperation and bravery spread because the groups that possess them win.

The grim math is that genocide only needs to happen very occasionally to be a powerful evolutionary force.

Yes.

Once intergroup aggression crosses a certain threshold, it becomes its own self -fueling engine for mental and cultural advance.

You have to get smarter to win or to avoid being annihilated.

So the rise of states wasn't driven by one thing, but by these complex interlocking cycles.

Exactly.

Population, communication, warfare, redistribution systems, they all feed back on each other.

The big picture is that human evolution went from being driven by external ecological pressures to being driven by internal social and mental reorganization.

Social evolution got its own motor.

Looking to the future, Wilson predicts that sociology is still in its natural history stage.

What does it need to become a mature science?

It needs a full neuronal explanation of the human brain.

The new neurobiology will provide the first principles, a mechanistic definition of emotion, judgment, and creativity.

And what's the role for sociobiology once we have that brain map?

A monitoring role.

Yeah.

First, to reconstruct the evolutionary history of that neural machinery to see what's obsolete.

Second, to monitor the shifting genetic basis of social behavior as global gene flow increases.

Because more gene flow means less relatedness within communities which could weaken altruism.

Precisely.

And that leads to the ultimate dilemma.

The fear that our most valued qualities like creativity and cooperation are genetically linked, pleiotropically, to our most destructive ones.

So cooperativeness might be bundled with aggression.

Or creativity with a drive to dominate.

If a future society eliminates the stresses that made those dark traits adaptive, the valued traits we love might whitter away with him.

Social control could, in a genetic sense, rob us of our humanity.

So this whole scientific journey leads us toward a total mechanistic self -knowledge, which comes at a philosophical cost.

A huge cost.

And Albert Camus captured the resulting feeling of alienation perfectly.

He wrote, A world that can be explained even with bad reasons is a familiar world.

But on the other hand, in a universe divested of illusions and lights, man feels an alien, a stranger.

His exile is without remedy.

That is the profound price of total self -explanation.

It brings us right back to the beginning.

We have to understand our biology from our stance to our morals before we can even begin to think about designing a better future.

It's the essential starting point.

There's no way around it.

A compelling, complex, and deftly challenging framework for understanding ourselves.

Thank you for walking us through all of that.

My pleasure.

It was a lot to cover.

That was our deep dive into the origins of the human biogram.

We hope you feel thoroughly informed.

We'll see you next time.