Chapter 5: Genes, Culture, and Gender

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Imagine for a second that an alien spacecraft has just approached Earth from light years away.

Okay, I'm picturing it.

The alien scientists on board are assigned to study this curious hyper social species called homo sapiens.

Right.

Us.

Exactly.

Us.

To do this, they decide to observe two randomly sampled subjects.

So first, they point their instruments at Jan.

Jan is this highly competitive, verbally combative trial lawyer who grew up in Nashville but moved to the West Coast for the California lifestyle.

Jan is on a second marriage and friends describe Jan as an independent thinker, very self -confident and maybe a little domineering.

Sounds like a pretty intense personality.

Yeah.

But then the aliens point their scopes across the globe at Tomoko.

Tomoko lives in a rural Japanese village literally walking distance from both sets of grandparents.

Oh wow.

Complete opposite environment.

Totally.

Tomoko is deeply family oriented, a loyal spouse, a protective parent and friends describe Jan and Tomoko as kind, gentle and profoundly respectful of the extended family's traditions.

So if those alien scientists only had a sample size of two, you really have to wonder what they would conclude.

Right.

Looking at the sheer contrast between Jan and Tomoko, would they think they were observing two completely different subspecies of primate or would their advanced alien instruments look past the external behaviors,

you know, the clothing, the language, the daily routines and actually be struck by the profound structural similarities operating just beneath the surface.

Welcome to today's deep dive.

We are sitting down with you for a specialized one -on -one session designed to answer that exact question.

Yeah.

We are exploring the mind bending intersection of genes, culture and gender.

We'll be using the foundational concepts from chapter five of social psychology, the 10th edition to decode the forces that make us who we are.

So let's unpack this because it is incredibly easy to focus on how different Jan and Tomoko are.

Oh, absolutely.

Or how different any of us are from our neighbors, honestly.

But beneath the customs and the conditioning, we are all running on the exact same biological hardware.

Yeah.

And to understand how Jan and Tomoko can live such drastically different lives,

we first have to understand the evolutionary foundation they both share.

Right.

This is the evolutionary psychology perspective, which fundamentally relies on Charles Darwin's concept of natural selection.

In fact, the philosopher Daniel Dennett actually called natural selection the best idea anybody ever had.

The best idea ever.

Yeah.

Because it elegantly explains both our physical and our psychological reality.

Well, I mean, it's easy to see how natural selection applies to physical traits, right?

Like a polar bear evolving thick white fur to survive in the Arctic.

Yeah.

But how does that mechanism actually shape our psychology?

It works exactly the same way.

Behavioral variations that increase an organism's chances of surviving and reproducing get passed down.

Makes sense.

Over countless generations, those helpful psychological traits become standard issue for the entire species.

Think about why humans universally prefer the taste of sweet, energy -dense foods over bitter ones.

Oh, because of calories?

Exactly.

Our ancestors who craved sweet fruits sought out the high calories they needed to survive and reproduce.

The ones who loved bitter flavors were far more likely to eat something toxic and die before passing on their genes.

So we are quite literally the descendants of the sugar lovers.

We really are.

And it goes way beyond food preferences, too.

We see this universal programming in early childhood development.

Oh, yeah.

The stranger anxiety.

Right.

By about eight months of age, human babies all over the world start showing an intense fear of strangers.

And that isn't something their parents teach them.

No, not at all.

It is a psychological defense mechanism, like an evolutionary alarm system, that kept our ancestors' infants from wandering off with predators or rival groups.

We are essentially mobile gene machines carrying the psychological legacy of our ancestors.

But here is the critical pivot.

Evolution didn't just program us with rigid robotic instincts.

Instead, it gave us an incredibly adaptable brain.

The social psychologist Roy Baumeister summarized this beautifully when he said,

I love that quote.

Evolution made us for culture.

Yeah.

Nature put humans on a very loose genetic leash.

Our shared biology is exactly what enables us to learn, adapt, and build vastly different cultural environments.

I love thinking about this dynamic like a smartphone.

OK.

How so?

Well, when you are born, you are handed the exact same physical smartphone hardware as everyone else on the planet.

You have the same basic operating system.

You feel hunger.

You recognize smiles and frowns.

You form social bonds.

Or at the baseline stuff.

But culture is the app store.

Depending on where you are born, you download completely different behavioral apps.

Oh, that's a great way to put it.

Yeah, you might download an app that values strict punctuality or one that values a more relaxed fluid sense of time.

And we can see these cultural apps dictating behavior in real time.

There is a fascinating field experiment conducted by a Dutch research team led by Kees Keizer back in 2008.

Oh, the bicycle one.

Yes.

They wanted to understand the mechanism behind how cultural norms, specifically around rule breaking, actually spread.

So they went to an alley filled with parked bicycles and attached completely useless promotional flyers to all the handlebars.

Which is incredibly annoying, but I guess a perfect setup for an experiment.

Exactly.

Now, this alley had a very clear, highly visible, no graffiti sign.

OK.

When the wall next to the bikes was perfectly clean,

only one third of the cyclists tossed the flyer under the ground as litter.

Still kind of a lot, but OK.

Right.

But then the researchers came back and covered that same wall in band graffiti.

Oh, wow.

When cyclists returned to find their bikes, the rate of littering more than doubled.

Over two thirds of people threw the flyer right on the ground.

Because the environment sent a new psychological signal.

Seeing the graffiti signal that the unwritten social contract of that space had already

Precise.

If nobody else cares about the rules here, why should I?

The immediate cultural context rewrote their behavior on the spot.

We also see these deeply downloaded cultural norms in how we interact with strangers.

Miles Patterson and Yuichi Iizuka ran a study where they had an actor walk down uncrowded sidewalks in both the United States and Japan.

I remember this.

Yeah.

When this actor made eye contact and smiled at passing pedestrians, the Americans overwhelmingly smiled or nodded back.

They automatically reciprocated the friendly norm.

But the Japanese pedestrians mostly avoided eye contact entirely.

And see, to an American, that might feel aloof or even rude.

But the underlying mechanism in Japan is completely different.

Exactly.

In a highly dense, historically crowded society, privacy isn't physical, it has to be psychological.

Avoiding eye contact reflects a deep cultural respect for privacy, a concept sociologists call civil inattention.

They are basically granting you the gift of being invisible.

What's fascinating here is how our genetic expression actually depends on these types of environmental interactions.

Right.

It's not just one or the other.

No.

We used to think genes were fixed blueprints.

But the field of epigenetics shows us they are much more interactive.

A famous study from New Zealand looked at a specific gene variation that puts people at a high biological risk for depression.

But having the gene didn't guarantee the depression, right?

Right.

The gene only caused depression if the person also experienced severe life stresses, like a terrible breakup or job loss.

Wow.

The gene alone didn't do it.

The stress alone didn't do it.

It requires the interaction.

Think of your genes like the keys on a piano.

The keys are fixed and identical for everyone.

But your environment and your culture are the musicians.

You only get music or, in this case, a specific behavior when the environment strikes the keys.

So if our environment has the power to play these genetic keys differently, it makes total sense that human living in vastly different environments would develop completely different cultures.

Absolutely.

But what blows my mind is that even within all that diversity, there is a hidden layer of code that looks identical across the globe.

We have profound cultural similarities.

We do.

Researchers Lung and Vaughn discovered that no matter where you go in the world, people organize their social beliefs around five universal dimensions, which they call the Big Five Social Beliefs.

And those are?

These are cynicism, social complexity, reward for application, spirituality, and fate control.

Let's look at reward for application, which is basically the belief that if you try hard, you will succeed.

Right.

Why does every culture on earth have to grapple with that specific concept?

It's because any functional society needs a mechanism to motivate effort.

Without a shared belief that hard work pays off, agriculture fails, infrastructure crumbles, and the group just doesn't survive.

Exactly.

These aren't just arbitrary ideas.

They are the necessary operating rules for human survival.

We also see universal rules in how human beings communicate status and power.

Social psychologist Roger Brown researched status hierarchies and found a very predictable norm in human language.

Oh, this is fascinating.

Yeah.

Everywhere in the world, people talk to higher status individuals using the formal tone and language they would use with strangers.

Conversely, they talk to lower status individuals using the familiar casual tone they use with close friends.

Let me push back on that formal versus familiar dynamic for a second, because I want you to think about how this plays out in your own life.

Think about the last time you went to a new doctor.

You probably called them Dr.

Smith, maintaining that respectful stranger -like distance.

But Dr.

Smith might have walked in and immediately said, hi, I'm Bob, or addressed you by your first name.

Why is it that the higher status person is always the one who sets the pace for intimacy?

Like, why do they get to decide when it's okay to drop the formalities?

Because yielding that formal distance is a privilege of their social position.

It proves that cultural communication isn't just random chaos.

Human nature creates universal, predictable patterns for navigating social power.

And if human nature creates these universal patterns for power, we have to look at how influences the most fundamental social category we are sorted into the moment we are born are gender.

Right.

The psychological definition of gender refers to the characteristics, whether biological or socially influenced by which people define male and female.

Okay.

But before we explore how men and women differ, we really have to start with the overwhelming reality of how similar we are.

Yes, the baseline.

The researcher Janet Shibley Hyde analyzed dozens of meta -analyses, basically synthesizing mountains of data.

And she concluded that your opposite sex is actually your nearly identical sex.

Nearly identical?

Out of our 46 chromosomes, 45 are completely unisex.

Men and women are virtually identical in overall vocabulary, creativity, intelligence, self -esteem and happiness.

The baseline is overwhelmingly the same, but the behavioral differences that do exist are statistically wild.

They really are.

For instance, men are five times more likely to be killed by lightning.

Five times?

Yeah, due to riskier behavior and outdoor exposure.

They are four times more likely to commit suicide and three times more likely to be diagnosed with ADHD.

Meanwhile, women are doubly vulnerable to anxiety and depression.

When social psychologists break this down, they group these behavioral gaps into four key social differences globally.

The first difference centers on independence versus connectedness.

Generally, women tend to prioritize intimate relationships and connectedness.

In the professional world, this translates to women gravitating toward vocations that reduce inequality in foster care, like teaching or social work.

Men, on the other hand, prioritize independence and competition, gravitating toward roles that enhance inequality and hierarchy, like corporate advertising or prosecution.

The second key difference is dominance.

Globally, men are more socially dominant.

The mechanism here is often conversational in group settings.

Men tend to talk louder, interrupt more frequently, and focus on problem solving rather than empathy.

The third difference is aggression, specifically physical aggression.

In every known culture on earth, men are more likely to engage in physically violent acts.

That's a huge one.

Yeah.

And the fourth difference is sexuality.

Across varied cultural surveys, men initiate sex more often and think about it much more frequently.

One study cited in the text showed 54 % of men report thinking about sex every day or several times a day compared to just 19 % of women.

Here's where it gets really interesting.

Because we need a mental model to understand these variations,

instead of thinking of men and women as opposite sexes, think of them like two folded hands.

Oh, I like that visual.

Yeah, they're deeply similar, sharing the same basic structure, but they are not exactly the same.

They fit together precisely because of the subtle ways in which they differ.

It is a profound way to visualize it.

But as scientists, we have to ask why those specific differences, particularly around aggression and sexuality, exist so consistently across every culture.

Right.

What's driving it?

This brings us to the evolutionary psychology perspective on mating.

Evolution predicts that we won't see sex differences in areas where males and females face the same adaptive challenges.

Like sweating.

Exactly.

We both sweat to cool down.

We both have pain receptors to avoid fire.

But mating and reproduction, that is where the adaptive challenges diverge completely.

Because the biological investment required is entirely asymmetrical.

For a man, the biological investment in creating a child can be a few minutes of time.

For a woman, it is nine months of intense physical taxation, followed by years of nursing and vulnerable caregiving.

Because women invest so much more heavily in offspring,

evolutionary psychology argues they evolved to be highly selective.

They needed to seek mates who displayed resources, status, and a willingness to protect that long -term investment.

Makes evolutionary sense.

Men, conversely, evolved to seek physical cues of youth and health, which are the biological indicators of fertility.

From this perspective, a massive amount of male behavior, from aggressive physical competition to accumulating extreme wealth, is essentially an evolutionary courtship display.

And biology also facilitates this through hormones, right?

Higher levels of testosterone are strongly correlated with physical aggression, which we see consistently in violent criminals and aggressive athletes.

Yes.

The data on that is very clear.

Fascinatingly, as people age and their testosterone levels naturally drop, the gender gap actually narrows.

Older women tend to become more assertive, while older men become more empathic.

That's true.

But let me push back on that evolutionary lens for a second, because, frankly, it sounds a little problematic.

Doesn't saying men evolved to be aggressive and seek multiple partners just give society a giant scientifically endorsed excuse for bad behavior?

Yeah, I hear that a lot.

Doesn't it just validate the whole boys will be boys narrative?

This raises an important question, and it is the exact critique leveled against evolutionary psychology by many scholars.

It's called hindsight bias.

Hindsight bias.

It's very easy to look at a current problematic behavior, work backward, and invent a convenient evolutionary reason for why it exists.

However, evolutionary psychologists clarify a crucial distinction.

Evolutionary wisdom explains what worked in the past to get our ancestors' genes into the future.

It absolutely does not dictate what is morally right, nor does it dictate what is actually adaptive in today's modern information -based society.

Right, because things have changed.

Exactly.

Physical aggression and dominating a hierarchy don't help you code software or collaborate in a modern corporate environment.

We are essentially running ancient software in a modern world.

That makes a lot of sense.

Evolution is our historical blueprint, but it doesn't lock us into a destiny.

Which brings us to the other massive force shaping gender, the culture we live in right now.

Yes, the cultural architect.

If evolution is the only driver, gender roles would be static.

But if we look at history, gender roles vary drastically across time and place.

Just look at the rapid global shift toward dual -career marriages over the traditional husband -as -provider model.

Very true.

Evolution doesn't move that fast.

That is the cultural architect at work.

And how does that cultural architect actually transmit its blueprints to us?

For a long time, we operated under what developmental psychologist Judith Rich Harris called the

The idea that parents matter most.

Right, the deeply held belief that parents are the primary molders of their children's personalities.

But data from twin and adoption studies dropped a bombshell on that theory.

Oh, this dad is wild.

Genetic influences account for about 50 % of individual variations in personality.

But the shared home environment, the actual parenting, accounts for a shocking 0 to 10%.

0 to 10%.

That is completely counterintuitive to how we think about raising kids.

Two children raised in the exact same family are, on average, as different from one another as two kids pulled randomly from the street.

It remains one of the most dramatic findings in developmental psychology.

So if genes are 50 % and the home environment is maybe 5%, what is making up the other 45 %?

Yes.

Harris argues it is peer influence.

Children learn their culture, their accents, their rules of play, and their gender roles from their playmates, not their parents.

If you have a preschooler, you have seen this mechanism in action.

You can beg and plead with your kid to eat broccoli at home and they will stubbornly refuse.

Yeah, every night.

But put them at a preschool table where all the other four -year -olds are eating broccoli and suddenly they eat the broccoli.

It's magic.

Right.

Why?

Because your peer group is your ultimate cultural transmitter.

That is the pool of people you are going to eventually work with and mate with.

So nature programs your brain to adapt to them, not your parents.

So we arrive at the ultimate puzzle.

Is our behavior driven by our biology or is it driven by our culture?

The big question.

And the answer, as theorized by Alice Eagley and Wendy Wood in their social role theory, is that they are completely dependent on one another.

They form an inseparable tangled web.

Eagley and Wood explain that biological -physical differences historically led to a division of labor.

Because men generally had more upper body strength, they did the heavy physical labor like plowing fields.

Because women had the biological capacity for childbearing and nursing, they did the caregiving.

But here is the mechanism that division of labor created societal role expectations.

Precisely.

Because men were doing physical labor and controlling resources,

society started expecting men to be tough and dominant.

Because women were caregiving, society expected them to be nurturing and submissive.

And then those expectations take over.

Those cultural expectations then began to proactively shape our behavior.

And Eagley's model predicts that as our societal roles equalize as physical strength becomes less relevant to earning resources and more women enter leadership while men take on caregiving, these behavioral gender differences will naturally lessen.

Consider a fascinating statistic regarding height norms.

In one U .S.

study, only 1 in 720 married couples featured a taller woman.

One in 720.

That is the stark statistic.

So, what does this all mean?

Ask yourself, is that height role a biological urge to ensure reproductive pairing?

Or is it a cultural norm designed to visually maintain male social dominance?

It has to be both.

The answer is both.

Biology dictates that men tend to be taller on average, but culture takes that biological reality and turns it into a rigid, enforced social rule.

What biology initiates, culture accentuates.

Which brings us to a profound philosophical and psychological crossroads to close out this exploration.

We've talked about evolutionary programming, loose genetic leashes, powerful cultural norms, and intense peer influence.

Yeah, we've covered a lot.

We stack all of that up, it can start to feel like we are just tumbleweeds, helplessly blown around by our genes and our societies.

It really can.

It feels like we have no agency at all.

But that ignores the great truth of social psychology, the immense power of the situation.

However, the physicist Niels Bohr once noted that the opposite of a great truth is also true.

The opposite here is the power of the person.

Yes, our situations and cultures influence us, but we interact with our situations in three vital, active ways.

Okay, what are they?

First, we interpret situations differently based on our unique individual minds.

Second, we actively choose our situations.

You choose to go to a specific college, or you choose to move to a liberal or conservative city, essentially picking the social forces you want to be influenced by.

And third, we create our situations.

Our preconceptions literally become self -fulfilling prophecies.

If you walk into a room expecting people to be hostile, your brain tells you to act defensively, which in turn makes the people around you hostile.

Exactly.

We aren't just passive products of our social worlds, we are the active architects of them.

We create the culture that in turn shapes us.

It is a continuous dynamic loop of biology and environment.

Which leaves me with one final provocative thought for you to take away from this session.

We started by talking about how alien scientists would view our shared evolutionary hardware.

Right, Jan and Tomoko.

We also know from Judith Rich Harris that 40 to 50 % of who we are comes from peer influence, because our brains are biologically wired to adapt to the peers around us.

But look at the world we are building right now.

Oh, where are you going with this?

What happens to human evolution and cultural transmission when our primary peers become AI companions or avatars in virtual reality?

If human nature is built to adapt to the culture of our peers, how will our biology respond when our culture is increasingly non -human?

That is a brilliant question to ponder.

You've got the foundational understanding now of how genes, culture, and gender interact to build our social reality.

Thank you for joining us from the Last Minute Lecture Team.