THE SECRET OF OUR SUCCESS:
HOW CULTURE IS DRIVING HUMAN EVOLUTION,
DOMESTICATING OUR SPECIES,
and MAKING US SMARTER
Princeton University Press
A PUZZLING PRIMATE
1 - We are good at long distance running. Other than that, we suck physically.
2 - We probably couldn’t out-survive a group of monkeys in the wild.
3- Why? Because we’re dependent on culture. This started maybe 1 million years ago.
And, it has resulted in culture-gene coevolution (he’s reversed the order!).
4 – Mechanisms like following prestige-imitating are built into us genetically.
5 – We transformed the environment we face via living in norms.
Our success is in our collective minds, not our individual ones.
6 – Innovation depends on our sociality more than intellect. Culture makes us smart.
IT’S NOT OUR INTELLIGENCE
8 – Including our domesticated species, we account for more than 98% of terrestrial vertebrate biomass.
9 – When humans arrived in America, 83 genera of megafauna went extinct, including horses, camels, mammoths, giant sloths, lions and dire wolves. This was a loss of over 75%.
10 – Ants, equal to us in biomass, are the most successful invertebrates.
11 – People think our success is due to our being smarter.
12 – But much of our brainpower comes, not from instincts, but from mental tools (integers), skills (left / right), concepts, (fly wheel), and categories (colors) we inherit from earlier generations.
13 – We do cultural learning. He’ll call the learning of our ancient ancestors and nonhumans ‘social learning.’ Social learning includes skills we can figure out on our own in a lifetime, such as cracking nuts.
SHOWDOWN: APES VERSUS HUMANS
14 – A group led by Herrmann and Tomasello tested orangutans, chimps and 2 ½ year old humans.
15 – We’re not as good on special tests, quantities and causality. But, we kill at social learning. But, we over imitate. Chimps eliminate the unnecessary parts of tasks. We include them as if superstitious.
MEMORY IN CHIMPANZEES AND UNDERGRADS
16 – Children and adolescents with greater working memory and info processing speeds at one age have better problem solving and reasoning skills at later ages.
In remembering patterns quickly flashed on a screen, Chimps beat us.
17 - We can be trained to be better though.
THE TRUE MACHIAVELLIANS
Perhaps our dominance comes from our social intelligence?
18 – Perhaps we got smarter because we had to out strategize against each other. But, in a game wherein one person got rewards for matching and the other person mismatching sides of a coin, we lose to Chimps. They are better strategizers.
To win you must randomize and we see patterns.
20 – We also imitate. In rock-paper-scissors there are more matches than normal. We subtlety see what’s coming and match the other.
21 – We believe we’re due! It is the gamblers’ fallacy. It means we can’t randomize well.
LOST EUROPEAN EXPLORERS
24 - The Inuits refused to help some lost Europeans because when they found them, they were engaged in cannibalism. European explorers, when stranded, usually die unless locals help them out.
27 – We don’t adapt by using individual intelligence. We don’t know what Inuits know about making harpoons and such.
30 - We don’t instinctually know how to get food, shelter and clothing.
32 – A final castaway of an indigenous tribe survived due to remembering cultural knowledge. When her rescuers came, she offered them dinner.
HOW TO MAKE A CULTURAL SPECIES
34 - “Cultural,” “biological,” and “evolutionary,” are not opposites.
35 - We have developed to where we can have a non-genetic (he stresses this) evolutionary process capable of making complex cultural adaptations.
36 – They hip us to who we should learn from and what we should attend to.
36 – If the high standard, high status model doesn’t reward himself with M&Ms, the kids don’t eat the M & M rewards either.
37 – Three cultural learning cues are age, success and prestige. Gender can help too.
SKILLS and SUCCESS
38 – We’ll model ourselves after those with the most scalps.
40 – This can mess up as people copy those who took risks and got lucky. And the more uncertainty, the more people copy cultural leaders.
41 – Infants and children do this. By one, they use clues to figure out who know things. And, then focus their learning, attention and memory.
When a child encounters something novel, they often look at their mother or a stranger for facial clues. This is especially true if the object their considering interacting with is novel.
42 – In a new environment, they look at strangers more than their mother. They also follow those who label things correctly.
We are also sensitive to body posture.
43 – They are 13 times more likely to use the toy from a prestige-cued model.
SELF-SIMILARITY: SEX AND ETHNICITY
44 – Many think gender role specialization is hundreds of thousands of years old in our species.
Ample evidence shows children and adults prefer to interact with, and learn from, same sex models. This happens even before the infants themselves have developed a gender identity.
45 – Neurologically, Elizabeth Losin at UCLA found imitating the same gender more rewarding. There was more firing in the brain’s reward centers.
Children preferentially acquire food preferences from those who share their language or dialect. And, children and adults prefer to learn from those who already share some of their beliefs.
African American students drop out of classes 6 percent less and get better grades when taught by AA instructors.
OLDER INDIVIDUALS OFTEN DO KNOW MORE
Children focus on learning from older kids, unless they are unreliable.
47 – Sometimes, they’ll take the younger if they are shown to be more competent.
WHY CARE WHAT OTHERS THINK? CONFORMIST TRANSMISSION
Would you pick the restaurant with 40 people eating in it or the one that is empty?
There is evidence of this in fish as well.
CULTUALLY TRANSMITTED SUICIDE
There are suicide epidemics in which the people who kill themselves match the demographics of the person committing suicide. And, the person killing themselves needs prestige.
49 - This happened in Micronesia and the people saw the ghost of older victims beckoning them.
51 – Toddlers, by 8 months, copy intentional, but not unintentional, actions. They infer others mental states and devalue what a person who mislabels has to say.
Some say this TOM evolved to help us be Machiavellian. He says NO! In their experiments, children copy the strategies of others, rather than exploit.
LEARNING TO LEARN AND TEACH
52 – Most people are not naturally great teachers. We’re great mimics. Apes raised by humans may be better at imitation.
53 – Our cultural learning seems to have developed as a response to enriched environments.
WHAT ARE BIG BRAINS FOR?
OR, HOW CULTURE STOLE OUR GUTS
54 - Our cultural knowledge accumulates across generations.
55 –Success leads to promulgation. This shapes our brains to look for more.
57 - And, cultural evolution becomes the primary driver of our species’ genetic evolution. The process is autocatalytic. It continues until outside forces constrain it.
58 – Increasingly, you need a brain capable of absorbing lots of information to survive. This is culture-gene evolution (note ‘culture’ comes first).
59 – 61 is an invaluable chart. It lists the Chapters Involved: the Culturally Transmitted Selection Pressures; the Coevolved genetic consequences; and Other implications. It should be read in its entirety! Herein are some examples.
Culturally Transmitted Selection Pressure
Coevolved Genetic Consequences
Specialized learning; longer childhoods
Demands for more childcare
Small teeth; colons, stomachs
Frees energy and favors sexual division of labor
Springy arches; shock enforced joints, innervated sweat glands
We become predators.
Folk biology: Increased knowledge about plants and animals
Category based induction
Taxonomies are universal (animals and non-animals).
Artifacts: Weapons and tools
Hands, shoulder, elbow change. Direct cortical / spinal chord connection
Greater manual dexterity, throwing ability. Increased weakness physically.
Wisdom of age
Extended childhood, menopause
Cooperative child rearing.
Complex Adaptation: High fidelity cultural learning
Theory of Mind; overimitation
Dualism; minds are not part of bodies.
Variation in skills / know-how
Prestige-based leadership and cooperation
Social norms: enforced by reputation and sanctions
Norm psychology: Shame / anger at norm violations / ability to see them
Strengthens effect of intergroup competition on cultural evolution
Ethnic Groups culturally marked
In-group v. out-group psychology.
Tribal ethnic groups; religions; nationalism
Change in throat, audio processing; tongue dexterity
Massive increase in cultural transmission
Communicative adaptations; white sclera; eye contact; pedagogical inclinations
Higher fidelity transmission.
BIG BRAINS, FAST EVOLUTION, and SLOW DEVELOPMENT
61 - Our brains are big and groovy.
62 – chimps’ brains are 350 cm3; ours 1350 cm3. This happened in 5 million years.
After 500cm3, it all happened in 2 million years.
We worked around our big head problem with dense cortical connections and post-birth brain expansions.
Myelin burns in gains, but makes us less able to learn.
At birth, childhood and adolescence chimps are more mylinated than us. For the neo cortex, chimps are 20% myelinated and us 0%.
63 - Adolescence is a particular myelination period. It is when we apprentice.
64 – Hunters do not produce enough to feed themselves till 18 and don’t peak until their late 30s. Some, not until their 40s.
We are ‘programmed to receive’.
65 – Fetuses learn aspects of language in the womb.
FOOD PROCESSING EXTERNALIZES DIGESTION
We have small digestive systems and our lip muscles are weak. Our mouths are the size of squirrel monkeys, who weigh 3 pounds. Our stomachs and colons are small. Why? We evolved with cooking, that does much of our digestion for us.
67 – Starting fire is so complicated that some foraging populations have lost the ability to make it.
Neanderthal fires went out for thousands of years.
68 – Bad cooking can actually increase toxins and make food more difficult to digest. So, our culture needs precise info.
Raw-foodists are thin and often hungry. Such women often stop menstruating or do so only irregularly.
Dan Fessler thinks this dependence has made kids fascinated with fire.
69 – Tools for food processing go back, likely, around 3 million years.
The energy savings from externalizing our digestion, went to the brain.
HOW TOOLS MADE US FAT WIMPS
Men cannot hold 85-lb adolescent chimps to the ground for a second. In the sideshow that did this, the chimps’ hands and mouths had to be taped to prevent major damage to the strong men trying to pin them.
70 – Tools and food processing allowed us to be small and survive.
Brains need a constant supply of energy. Periods of scarcity are a serious threat to humans. Nature has trimmed our energy budget.
71 – Children ask you what things are for? rather than what kind is it? When asking about artifacts. Plants and animals trigger’ what kind is it?
HOW WATER CONTAINERS AND TRACKING MADE US ENDURANCE RUNNERS
72 - We have domesticated animals for endurance. But, most species poop out.
We have springy feet arches; we have longer legs; we have controlled rather than fast-twitch muscles; we have big buts to stabilize us and spine muscles, our wide shoulders and short forearms make a swing when we run; our head twists independently of our body; other primates do not have skull cushions – we and other running animals do.
73 – We are also the sweatiest species. We have nearly zero hair and a head cooling system uses blood to cool our brains. All this is to allow the heating effect of endurance running .
74 – Prime athletes can sweat 2 liters and hour. How to compensate? We have water containers. This means our fancy sweat regulation could only take off after the cultural evolution of water transportation.
76 – We can spot weak animals via many indicators – age, etc.
77 – Skilled hunters vary their speed to stress animals during sprints.
THINKING AND LEARNING ABOUT PLANTS AND ANIMALS
Children quickly put animals and plants into essentialized; hierarchical; category – based induction and inheritance logic. This is not automatic.
80 – Children put everything in their mouths, except plants. For this they watch others to get a ‘go-ahead.’
81- Infants choose fruit over fruit – like objects. They know. But, if the model puts them behind their ears, that nullifies the difference. These are for ‘eating things’.
Note that this thinking is categorical, not just the individual object but they know food objects from non-food / plant from non-plant objects.
WHY SOME PEOPLE HAVE BLUE EYES
83 – Folate is crucial during pregnancy and lacking it can lead to birth defects. This is why pregnant women take folic acid. For men, folate is important for sperm production.
UV rays can dismantle folate if not blocked by melanin.
84 – Farther from the equator there is less UV to damage folate. But, darker skin means less vitamin D. Vitamin D is necessary for the proper functioning of brains, heart, pancreases and the immune system.
Vitamin D is so important that it favors light skin.
If races get lots of vitamin D, this is not so important and people far from the equator like Inuits (fish) can have darker skin.
In the Baltics, people became reliant on agriculture and so had no fish and vitamin D rich meat. This made for really light skin. The blue and green eyes are just nearby on the genome.
85 – This likely took about 6,000 years.
Culture can catalyze and drive more rapid genetic evolution.
He is reticent to hook culture to specific genes and continued culture-gene evolution. Why? 1) Many have completed and so no longer are under selection pressures; 2) Many are linked to various spots on the genome; 3) this science is in its infancy.
RICE WINE AND ADH1B
86 – Most primates don’t process alcohol well. But, when we moved to the ground, around 10 million years ago, and started eating more rotting fruit, our tolerance increased.
Between 7 and 10 thousand years ago a gene flipped (ADH1B)
and allowed us to process alcohol more efficiently. But, the side effect is that people have a bad reaction to
This makes people sort of allergic to alcohol. It reduces alcoholism by 2 – 9 times and excessive drinking by a factor of 5. But, it makes hangovers worse.
88 – The gene is predominantly in East Asia and a tad in the Middle East. Rice wine happened in China. And, created alcoholism. This favored the variant of ADH that made drinking less fun.
WHY SOME ADULT HUMANS CAN DRINK MILK
90 - Most babies drink milk, but not adults. Then we domesticated animals. Those who drank milk, but did not develop the lactose-benign cheese, yogurt and kumis, got lactose tolerant.
91 – African variants allowing milk drinking are oldest. European between 7,450 and 10,250 years ago, and the Middle East one from 2 – 5,000 years.
92 – Lactose, alcohol and skin are the 3 best documented and wildly taught examples. But, KEVIN LALAND and his team have fingered over 100 genes that have been under selection, that seem to have a cultural origin.
This study is called Niche Construction Theory.
Wade wrote (not in this book) that some 10% of the genome – 2,000 – genes show signs of being under selective pressure.
Examples include, dry earwax, malaria resistance, skeletal development and digestion of plant toxins.
93 – While the eye, lactose and alcohol ones are all agricultural, this has been going on for a long time. There is the cooking and fire revolution, the projectile-weapon revolution, the spoken word revolution and more.
How much starch was in your ancestor’s diets determines how much AMY1 starch digestion gene copies you have. Even close groups can have different numbers based on their historic diets.
94 – Patrilocal communities show more variation in their Y chromosomes and Matrilocal more in their mitochondria.
GENES AND RACES
95 - Looking at lactase persistence, for example, he sees variation within and across ‘races’ and so considers it unreal. Selection operates on scales much smaller than race.
Overall, traditional racial categories capture only about 7% of the total genetic variation in our species.
96 – We counter racism by more science and understanding why people lump people into categories.
ON THE ORIGIN OF FAITH
97 - Manioc is a staple that is poisonous if not properly prepared.
98 – Tukanoan women spend a quarter of the day detoxifying it. What if a mother failed to pass this info on to her daughter? What if she found an easier processing way that failed to remove the toxins?
99 – In this situation, individual learning does not pay. Function cannot easily be inferred from the steps.
Cultural evolution is often much smarter than we are.
100 - Prestige mechanisms happen because people place their faith in cultural inheritance – in the accumulated wisdom implicit in the practices and beliefs derived from their fore bearers.
TABOOS DURING BREAST-FEEDING AND PREGNANCY?
Such taboos in Fiji exclude toxins from the diet.
101 – They learn this from wise elders. This is a cue of success and knowledge. When asked, people said they did not know why.
102 – When asked for a reason, people say ‘it’s a custom’ or come up with a plausible reason on the spot.
WHY PUT ASH IN THE CORN MIX?
104 – There are many examples, in many cultures, of odd food practices with practical reasons. We just miss this because we’re used to safe food in supermarkets.
DIVINATION AND GAME THEORY
105 – As we learned with chimps, we are bad randomizers. We find it hard to shut down prediction mechanisms. We think “we’re due” when we lose many times.
Divination rituals may be crude randomizers.
106 – Rice cultivation is benefitted by randomizing and so since the 17th century bird augury has evolved. In Borneo, bird augury has spread most in the areas wherein randomization is most adaptive.
Making arrowheads is very complex, even at its simplest. Why do people heat the wood? They don’t know. But it is best. We see this kind of occurrence at every step.
“OVERIMITATION” in THE LABORATORY
108 - People don’t bother with ‘why they do it’. They don’t care. Missing a step can lead to serious diseases.
109 – People are more likely to copy irrelevant steps when the model is older and higher in prestige – as we saw. But, we’re more likely than Chimps to copy irrelevant steps.
He says, even though chimps have some culture, they are not a ‘cultural species.’
OVERCOMING INSTINCT: WHY CHILI PEPPERS TASTE GOOD
110 – People in hotter climates use more spices, and more of the most effective bacteria killers – (garlic, onions, coriander). Norway, not so much.
111 – Recipes use spices in ways that increase their effectiveness. Onions and garlic’s antibiotic powers are resistant to heating. And, so they are deployed in cooking. Cilantro is not.
Chili peppers have chemical defenses, basedon capsaicin, that directly trigger a pain channel in mammals.
People come to like them by reinterpreting the pain signal as enjoyable. They want to eat them like those they admire.
112 – Chili pepper eaters don’t know they’re being protected from meat borne pathogens. They just follow the culture.
MOVE OVER, NATURAL SELECTION
113 – Pinker and Buss are into evolutionary psychology and so say only natural selection selects. They love spider webs. This is true, but not ‘only true.’
114 – At least since the rise of cumulative cultural evolution, natural selection has lost its status as the only ‘dumb’ process capable of creating complex adaptations.”
115 – Birds build complex homes and so do we. Birds pass them on genetically, we do so culturally.
116 – “We cant assume that the complexity comes from either natural selection acting on genes or intentional construction. It might be a product of cumulative cultural evolution. Cultural evolution is smarter than we are.”
PRESTIGE, DOMINANCE, AND MENAPAUSE
118 – Prestigious leaders are often known for their generosity.
119 – We have developed emotions and motivations that take us to skilled models. Sadly, we follow them even if they turn out to not be skilled. We don’t directly evaluate, we evaluate prestige.
120 – This copying often includes the model’s personal habits or styles as well as their goals and motivations, since they may be helpful. The rule is ‘when in doubt, copy it!’
In primates and humans individuals attain dominance via violent intimidation.
121- “Subordinates signal their acceptance of a lower rank with displays involving diminutive body positions, including narrowed shoulders and a downward gaze. Dominant individuals remind subordinates of who the boss is with expansive body positions, upright torsos, widely spread limbs, and broadened chests.”
In primates dominance provides a fairly stable order.
We came to also develop prestige as a marker of social status. Dominance and prestige are different.
122 – The offspring of prestigious men die less frequently. And prestigious men marry at younger ages. In a study this held for prestigious men, but not dominant ones.
KEY ELEMENTS OF PRESTIGE AND DOMINANCE
123 – Another great chart!
Based on Coercion and Threat
True persuasion and deferential agreement.
Imitation by lower-status
No imitative bias except to satisfy dominant
Preferential, automatic, and unconscious imitation. May include affiliateive imitation.
Attention by lower status
Tracking of higher-ups, avoidance of eye contact, and no staring.
Directing of attention to and gazing at higher-ups, watching and listening.
Sociolinguistic behavior by higher-ups
Seizure of the floor and use of aggressive verbal intimidation. (disparaging humor and criticism).
Given the ‘floor’ and permitted long pauses. Uses self-deprecating humor.
Mimicry by lower status
No preferential mimicry
Preferential mimicry of higher ups.
Proximity management by lower status
Avoidance of higher-ups; keeping distance to avoid random aggression.
Approach to higher – ups; maintenance of proximity to higher ups.
Diminutive body position, shoulder slump, crouching and gaze aversion.
Attention to prestigious open-body position.
Expansive body position, expanded chest, wide stance, arms wide
Similar to dominance display except muted. Less expansive use of space.
Lower – Status
Fear, shame, fear-based respect
Admiration, awe, admiring respect
Hubristic pride, arrogance
Authentic pride, tempered arrogance
Social behavior by higher-ups
Aggression, self-aggrandizement, egocentric
Prosocial, generous, and cooperative
Higher-ups have greater fitness in small-scale societies.
Higher-ups have greater fitness in small-scale societies.
124 – Dominant individuals ted to be overbearing, credit themselves, use teasing to humiliate others, be manipulative. Prestigious foks are self-deprecating, attribute success to teams and tell jokes.
IMITATION, ATTENTION, and MIMICRY
124 – Lower – status individuals preferentially attend to and imitate prestigious individuals, but not dominant ones.
125 – Larry King imitated Bush, but not Dan Quayle.
126 – We do have the Paris Hilton effect due to all this. People who are famous for being famous.
STATUS DISPLAYS AND EMOTION
Dominants glare at others.
127 – Photos show a blind and sighted judo player make the same pride displays.
WHY PRESTIGIOUS PEOPLE ARE OFTEN GENEROUS
During the early centuries of Christianity, St. Ambrose worked to make giving to the poor admirable. Rich Christians began to compete for who could give the most.
129 – Why do prestigious individuals take the lead in giving? They can increase the overall prosociality of their local group or section of the social network. If low prestige people do so, no one follows.
130 – Sometimes the link is so tight that giving becomes a marker of prestige.
In the lab, if the gold starred prestige person gave more, so did the lower person. But, they only did so when they thought low prestige players would follow this action.
PRESTIGE AND THE WISDOM OF THE AGES
132 – Accumulated knowledge explains why the elderly are prestigious in most, if not all, traditional societies.
It’s also why most other animals don’t respect their elderly.
133 – But in a time of rapid change, the young get more respect (see the West).
MENOPAUSE, CULTURE, AND KILLER WHALES
133 – Older people knowing more, means that natural selection should extend our lives. This is why nearly only humans live well beyond their reproductive years.
134 – Evidence is just starting to be gathered, but it seems folks with grandmothers are more likely to survive.
135 – Killer whales and elephants live decades beyond their reproductive years.
It seems that killer whales are really good imitators. Moms teach the young how to beach themselves and rescue them when they get stuck.
Older matriarch elephants are better at identifying predators.
LEADERSHIP AND THE EVOLUTION OF HUMAN SOCIETY
137 – In egalitarian societies prestige lays a crucial foundation for politics and economics.
138 – Many modern institutions also promote those of status. The Jewish Sanhedrin Court has the lowest member members speak first. Otherwise, they may not speak at all. Our US Supreme Court goes the opposite way.
IN-LAWS, INCEST TABOOS, AND RITUALS
141 – In tribes, cousins sometimes get labeled as ‘brothers’ and ‘sisters’ but they know the difference. You can be touched by your real sister, incidentally, but not by a cousin (temptation is real).
142 – Dawkins and Pinker exclusively promote kin selection and reciprocal altruism as the basis of cooperation.
143 – But culturally constructed norms greatly augment our innate proclivities.
SOCIAL NORMS AND THE BIRTH OF COMMUNITIES
Cultural learning means that it’s possible for people to acquire notions of how people should behave, both toward others and even in purely nonsocial situations.
144 – When people imitate prestigious folks, this
turns to norms. This is
backed up with mathematical models.
Gossip helps create such norms. And, such norms tend to remain stable
even when they help neither the group nor the individual.
(examples include cliterectomy and eating brains at funerals).
145 – Third party monitoring and the emotion of disgust help.
FROM KIN TO KINSHIP
Marriage norms and customs bolster this flimsy pair bond instincts.
146 – 85% of human societies permit polygamous mating.
Marriage institutions include who can marry whom, how many partners, inheritance rights and legit heirs, where the couple will live and rules regarding sex outside of the pair bond.
Most all societies have social norms that regulate the wife’s sexual fidelity, but about one quarter also regulate the husband.
147 – The community elongating the bond also connects him to ‘affines’.
Babies are often named after grandparents on the father’s side. This balances out paternity uncertainty.
148 – Sharing similar names increases liking for people and their willingness to help.
150 – Some few societies have little pair bonding. They develop other institutions, like taking care of your sister’s kids. And, shaming those who are jealous.
FROM INCEST AVERSION TO INCEST TABOOS
152 - Unlike most other primates, human brothers and sisters form long and enduring social bonds. This even though they may be in different tribes via women leaving. And, the sibling category gets generalized to my ‘brothers and sisters’, though all know the difference.
154 – So, these are not just kin selection, but bonds culturally reinforced. This suggests that stripped of our cultural bonds we aren’t nearly as cooperative or communal as we might seem.
SOCIALITY AND COOPERATION AMONG HUNTER - GATHERERS
155 - Hunter gathering groups are renowned for their cooperation. A chart shows, that even in small tribes, we’re related to very few folks. This means about ¾ of band relationships are based on something besides genetic relatedness.
156 – 2/3rds are spouses and affines. Marriage norms therefore create over half the ties in adult relationships within a band.
The remaining quarter are still referred to with kinship terms.
157 – Food sharing is also governed by norms and ‘cultural technology.’ It is often given to a 3rd party to distribute. Because they didn’t do it, they may be more objective about sharing.
It is often taboo for the animal killer to eat certain parts.
158 – These are not just for avoiding disease. They rarely violate the taboo so it would have no effect. Also, we already don’t eat meat with pathogens.
159 – If people question the taboo, they will be met with vivid counter examples.
People bind against external forces of evil and they bind together on an intimate social level with rituals.
160 – Recent systematic measurements of rituals’ impact show the strength of:
1) Synchronous singing and dancing or other movements (marching);
2) collaborative music making;
3) extreme physical exhaustion;
4) feeling of a common fate;
5) shared experiences of terror or danger;
6) supernatural or mystical beliefs;
7) causal opacity or lack of instrumentality (ie people don’t know why something must be done a certain way, but they know it must!)
Those who sang along and moved together to the Canadian national anthem gave more to a shared project, than those who only did one or the other simultaneously.
161 - The terror of initiation rites bonds people well and so is near universal. And participants are scared!
THREAD IN THE FABRIC OF SOCIAL LIFE
162 – In many foraging societies, band membership is quite fluid. If people wish to leave, they can find kin in nearby groups to take them.
163 – By contrast chimps kill outsiders.
Who helped tribe folk when ill? Family and affines will. But, they are about 15 - 20 % of those you meet. And affines were 50% more likely than others to have given food. Fake relations like ‘God parents’ helped too. People have more cultural relations than actual ones.
Men in rituals relationships help too. And, these are ABSENT in primates. So
this explains a lot about cooperation.
And these cultural relationships can extend across tribes.
165 – These norms work even though people don’t understand why they exist and, we’ll see, they probably work better because we don’t know.
INTERGROUP COMPETITION SHAPES CULTURAL EVOLUTION
166 – When followed, over 9 years, a chimpanzee troupe made 114 border patrols and killed 21 members of other troops.
The estimates are that about 3/4 s of the chimpanzees in other groups can expect to be murdered by a patrol before turning 50. And the raiding troup expanded their territory by 22.3% in 9 years.
167 – When we started to differentiate culturally, we were probably already living in stable groups. Many rituals, etc, seem designed to harness our social instincts. How could they have been started?
Intergroup competition may explain some of it. Consider five forms of intergroup competition:
1) War and Raiding:
This can drive out or assimilate those without norms.
2) Differential group survival rates without conflict.
(168) shocks like drought might exterminate or disperse those without norms.
3) Differential migration:
Many individuals will be more likely to immigrate into successful groups.
4) Differential reproduction:
5) Prestige-biased group transmission:
People follow those who are successful in successful groups.
169 – Over time, combinations of these intergroup processes will aggregate and recombine different social norms to create pro-social groups.
Prosocial means behaviors that lead to success in competition with others (NOT good or better). Labelling out-groups as non-humans is not better. But, it works better.
HOW OLD IS INTERGROUP COMPETITION?
There are many cultural evolutionary forces that do not favor pro-social institutions.
170 – When there is no intergroup competition, people will be more inclined to seek out their own advantage within the tribe.
Chimps killing 4% to 13% of outgroups, intergroup competition likely started prior to cultural evolution and may have thus formed norms right away.
171 – 70 – 90 % of hunter – gatherers had continuous (every year) or frequent (once every five years) warfare. And, it seems deaths from said conflict were 13 – 15%. This is in line with chimp estimates.
The territory gained and lost seems to have averaged 16% a generation (25 years).
172 – Varying weather means Paleolithic conflict may have been even more than our data suggests. An analysis from California shows that in 7,000 years there was more violence when the weather was unstable.
173 - When one New Guinea group David Boyd studied was beating all others, another group just decided to take all of their norms. This though the practices did not necessarily have a logical connection to success.
174 – This makes sense “Since we humans are terrible at designing institutions from scratch.” This copying of institutions and rituals seems to be common place. Sometimes, less successful groups would pay the more successful to teach them.
175 – Cross cultural data shows warfare is associated with the presence of more terrifying and costlier rites for males.
176 – Much of the evidence we have about one group taking over another is farmers taking over a tribal group. This hurts our evidence of competition being key in spread. Let’s look at Australia when whites arrived.
THE PAMA-NYUNGAN SPREAD
180 – The data herein suggests either differential reproduction or violent conflict, prestige biased group transmission and differential migration.
THE SPREAD OF THE INUIT AND THE NUMIC
By sharing his wife an Inuit could cement a beneficial relationship and a bond between his and the man’s children.
181 – Differential extinction likely played a role.
Gathering over large areas would favor groups that could still maintain bonds, though dispersed.
183 – Neanderthals also appear to have been copying newcomers from Africa, suggesting prestige-based group cultural transmission.
Overall the evidence indicates that violent and non-violent intergroup cooperation has been important.
186 - When 3 – year olds watch a teddy bear do actions, they protest against others doing ‘aberrant’ actions.
They do this without direct teaching. They know to judge aberrant behavior. No adult ever reprimands.
187 – Our ancestors would have been increasingly molded by norm acquisition pressures.
189 – This has driven self-domestication via a norm psychology that has several components:
1) We assume the world is rule governed, even if we don’t yet know the rules. This means we assume that others behavior is rule governed and contains norms.
2) When we learn norms, we partially internalize them as goals in themselves. This means our instincts match that the society wants.
Kids in the experiment assume there are norms and get angry when they are violated.
190 – A generosity experiment showed people spontaneously imitate models. They repeat statements by a model. They say why they give to the poor in the words others use. Third, the behavior is stable for weeks or months in retests. Fourth the kids impose the same behaviors and ideals on others.
The kids are not just learning to be generous in a general sense, they are getting norms for the specific task / situation.
HOW ALTRUISM IS LIKE A CHILI PEPPER
Here we look at the Prisoner’s dilemma, the Ultimatum game, and the Dictator game.
191 – In the Ultimatum game you have $100 and must propose a division to another who can accept or reject.
192 – Chimps never reject in the ultimatum game. In Western societies people offer half.
In the dictator game, you give whatever you want and people
can’t reject it. Most
western adults continue to hive half. That is because we have large societies wherein people
do impersonal norms.
In small scale societies, people do not offer much. They lack the social norms for monetary exchanges with strangers.
However, in repeated trials, lab specific norms emerge.
193 – In the Public Goods game, people only interact
once. People do best if everyone
is generous. But, if you withhold,
you may do best as an individual and all others cooperate. You are given $4 dollars
and must contribute. Whatever goes
in the pot is doubled and then distributed equally among all four.
194 – The more rapidly people decided the more they contributed. The gut instinct is cooperative.
195 – When placed under time pressure, folks from some societies get angry and reject offers quickly. This shows negative emotional reactions are our automatic and unreflective response to norm violations and norm violators.
In the ultimatum game, people in small societies don’t expect people to pitch in half and don’t punish those who don’t.
AND IN THE BRAIN
196 – Neurologically, people like to comply with norms and punish violators. We are built to be norm followers.
WHY SPOTTING POTENTIAL NORM VIOLATIONS IS EASY
198 – Shame evolved from subordination signals. Shame and proto-shame have the same behaviors.
Shame displays reaffirm acceptance of the local social order.
199 – These psychological adaptations evolved by the spreading of intergroup competition because they: a) suppressed the harming of the community; b) prescribed equitable treatment to peers; c) established enduring status relationships.
Infants like puppets who help people and don’t like those who hinder people. BUT by 8 months, babies prefer puppets who hurt anti-social people.
NORMS-CREATED ETHNIC STEREOTYPING
200 – Whereas Chimps kill strangers, we can welcome them if we have established community via relevant symbols and greetings. This allows us to navigate a world of our own creation. If we have the right norms, we can interact. If not, problems ensue.
201 – But social norms are tricky because they are often hidden until it is too late. You may fall in love with an African and only learn later that he’ll circumcise your daughter.
We have observable markers for that reason. Tattoos and dialect. This shows if the person is likely to share your norm.
Children preferentially learn tool use and food preferences from those who share their language or dialect.
202 – Children would rather interact with those who share their language and their mother’s dialect by 10 months.
People in Michigan try to imitate Chaldeans for this reason .
203 – Children punish puppets who share their accents more than those who don’t.
204 - They favor them and subject them to more norm enforcement.
A) Intergroup competition will favor the spread of any tricks for expanding what a tribe member perceives to be their own tribe. They create quasi tribe for this reason:
B) Not all groups are equally salient. Civil wars strongly trace to ethnically or religiously marked differences and not to class, income, or political ideology.
C) our thinking about race actually evolved to parse ethnicity, not race. Ethnicity being culturally transmitted markers and race morphologically genetically transmitted.
205 – This has been seen in studies wherein accent trumps racial differences when children choose who to be friends with. Even weaker cues like dress can sometimes trump racial cues.
But, the tendency of children and adults to preferentially learn and interact with those who share their racial markers (mistaken for ethnicity) probably contributes to the differences between racially marked groups, even in the same neighborhood.
WHY KIN-BASED ALTRUISM AND RECIPROCITY ARE
SO STRONG IN HUMANS
206 – Humans help relatives more often than other mammals. We get half-siblingsand they don’t.
Social norms contribute to kin-based altruism. For reciprocity, the effect
of social norms may have been even stronger. For example, in New Guinea my failure to offer my
sister as a wife for yours would greatly increase the chance that I’d later be
found guilty of witchcraft and then executed by the community!
WAR, EXTERNAL THREATS and NORM ADHERENCE
207 – Michael Gilligan found people from communities that had war violence (in Nepal) shared more in the Public Goods Game. This is the effect of strengthened norms. This came from new, post-war, organizations.
208 – Why would war have pro-social effects? Gene culture, co-evolution likely favored solidarity in times of trouble. This means cues of intergroup competition should promote greater solidarity and identification with one’s group.
209 – Studies showed war has its maximum impact on
sociality from 7 to roughly 20 years of age. It sharpens egalitarian norms for
the ingroup. And, the effect
endures for at least a decade after the conflict.
It does not impact sharing with distant strangers (not involved in the conflict).
210 - Those outside of this age showed a very small increase. So perhaps WW II did create the greatest generation.
OUR COLLECTIVE BRAINS
211 - When an epidemic killed its Inuit’s eldest members, they lost the ability to make many artifacts. The population declined until they met another Inuit group.
212 – Our power is in our collective brains. We cannot recreate things individually.
213 – More minds create more lucky errors.
214 – If you want cool technology, it is better to be social than smart. As our species became domesticated, we learned to learn.
TO THE LABORATORY!
215 – In one group, 5 modeled a behavior. In another, only one.
216 – In the 5 teacher group, participants looked at one the most, but learned from all. This can create ‘innovations’ without ‘invention,’ via recombining.
In larger tested groups, those who could learn from more models evolved better arrowheads.
SIZE AND INTERCONNECTEDNESS IN THE WORLD
217 – In a survey, islands with larger populations and more contact with other islands had both a greater number of different fishing tool types and more complexity.
218 – This holds for orangutans too!
THE TASMANIAN EFFECT
219 – When they shrunk in population, some information was lost every generation, because copies are usually worse than the original.
222 – The Tasmanians were cut off from the mainland by rising seas for 8 – 10 thousand years.
TASMANIA IN THE LAB
223 – Again when there are fewer models, technology degenerates.
224 – Again, our sociality is increased by norms and cultural technology, like rituals and ceremonies. The point is, “If intergroup competition is favoring sophisticated tools and weapons, it has to favor the social norms and institutions that can sustain a larger collective brain – technology and sociality have to coevolve.”
CHIDREN VERSUS CHIMPS AND MONKEYS
In a task, kids way outperformed Chimps. The kids who did better imitated others, and received instruction more often. The chimps never taught or did altruistic giving.
INNATELY DUMBER THAN NEANDERTHALS?
He asked hi class to rate the intelligence of toolmakers by looking at tools. But, that is not possible. It depends on group size.
226 – In primates, the strongest predictor of cognitive abilities is brain size. Thus it is not implausible that we were dumber than the bigger brained Neanderthals.
We may have been a touch dumber but had larger collective brains. Perhaps we had longer adult lives. Due to ice – age Europe and changing ecological conditions , Neanderthals lived in smaller scattered groups.
227 – In fact, they may have needed bigger brains to compensate for the lack of communal learning.
228 – Bows and arrows may have emerged 70,000 years ago. But, upon European contact, there were none in Australia.
TOOLS AND NORMS MAKE US SMARTER
229 – There has been genetic evolution, but lets put genes aside and consider them fixed. Only chimps in larger groups figured out ‘honey dipping.’
Australia also had no tools using compressed air, such as blow darts.
230 – Thus they had no models of technology to recombine. The abacus makes people better math solvers. They can even do it when there is no abacus present.
And when we use spoken numbers, we too rely on cultural artifacts.
COMMUNICATIVE TOOLS WITH RULES
231 – How language came about has long fascinated folks. It seems to come from long-term cumulative cultural evolution. And this pushed genetic evolution.
232 – “These genetic evolutionary pressures were powerful, shaping both our anatomy and psychology: they pushed down on our larynx to widen our vocal range, freed up our tongues and improved their dexterity, while whitened the area around our irises (the sclera) to reveal our gaze direction, and endowed us with innate capacities for vocal mimicry ad with motivations for using communicative cues.”
Remember, language was merely one element in a broad and synergistic process of culture-gene co-evolution. We gained and lost linguistic tools, just like Tasmanians.
233 – Linguists have assumed that all languages are equally complex, but it isn’t true.
COMMUNICATIVE REPERTOIRES CULTURALLY ADAPT
Fetuses begin acquiring elements of the sounds and rhythms of the language spoken by the mother, even before birth. Infants watch tongue and mouth movements.
At the end of the 1st year, children interpret pointing as a request to aim their attention. They use the same cues of competence, reliability, and ethnicity, (dialect) that are later used for learning about tools, practices, and social norms.
234 – We have gestures, body positions, facial expressions and vocalizations in addition to language.
SIGN AN WHISTLE LANGUAGES
235 - Signs and gestures are not a sideshow. Fully fledged sign languages were common among hunter-gatherers, both in Australia and North America. Plains standard sign language was used between tribes.
236 – Sign languages occur mostly in populations that had ritual restrictions on speaking for many months or years.
237 – These languages are neither complex nor iconic. In people with large territories, whistles are often used to communicate.
238 – Sonority decreases airflow and is in vowels like ‘a’. and the lowest in stops like ‘t’.
Languages in warmer climates rely more heavily on sonorant sounds, like N, L and R. In colder climates, less sonorous vowels, such as the ‘I’ in deep. Forests have less sonority.
239 – Such factors account for 4/5ths of the variance in sonority.
CULTURALLY EVOLVING COMPLEXITY, EFFICIENCY,
To spread, languages need to be learnable.
240 – So it is effected by population size, social networks, ethnicity, stratification, technology (writing), and institutions (formal schools).
Many languages have 3 – 4,000 words. English 17 year olds have 60,000 words. Professors have 73,000.
English has 11 colors; Korean 14; many only 2 or 3 (light
241 – Homer and the Vedas only have a couple of colors. This is not genetic, it is to do with cultural abilities.
242 – But, Western children now master color at an earlier age than generations past. This suggests cultural evolving to be better at transmitting this information.
243 – Our vocabularies and IQs have been increasing for a half a century. He explains the Flynn effect via vocabulary. This comes from increased verbal job requirements.
Words are like other parts of the culture, they expand with the increased collective brain. And may give us new cognitive abilities and raise our IQ.
244 – Languages vary greatly n the number of phonemes they have. But why? Databases show languages with more speakers tend to have more sounds. They have more phonemes and shorter words.
ROUTES TO GRAMMATICAL COMPLEXITY
245 – We can understand a story in headline – ese. We get bsics if temporal. But, grammatical complexity can evolve around that. This comes from hijacking concrete words and then bleaching them of their meaning and then honing them down.
246 - This process is called grammaticalization.
Concrete is now an adjective, for example.
247 – These spread as successful communicators, increase efficiency or expressiveness.
248 – In early languages they don’t have subordinate clauses. This makes them ponderous to read.
In larger populations with heterogeneous speech communities, we get simpler grammar.
CULTURALLY EVOLVED TO BE LEARNABLE
Like tools fit our hands, language fits our brains. Languages that are hard for children to learn got screened out in the competition.
As vocabularies increased there was added pressure for regularity and grammar emerged. – ed as the past got added, regularly.
250 – You have irregular verbs, but only on words that get used frequently so they can be memorized. Cultural evolution is why languages are easy for kids to learn.
THE SYNERGIES OF MANUAL SKILLS, NORMS, GESTURES, AND SPEECH
251 – Genes pushed our larynx down to widen our vocal range. It drove our neocortex down into our spinal chords to improve the dexterity of our hands and tongues and widened our sclera, and endowed us with a facility for mimicry.
If tools were driving some of this evolution, then language would have gotten a free ride.
Outside of some birds, who have the same brain set up, mimicry is rare in nature.
252 – There would have been a lot of pressure for using verbal gestures to communicate to free our hands for using tools, cooking, communicating at night, etc.
Apes watch the orientation of heads, whereas human infants watch eyes.
253 – Motherese. With only language, it is unsure where these abilities might have come from. They make more sense as a part of a co-evolutionary suite.
Complex tools are assembled sequentially, hierarchically, and sometimes, recursively, just like modern languages.
Grammar is similar to spear building. Food processing too involves sequential protocols with subcomponents, which must be done in order.
254 – In competing with chimps we only win when the behavior being copied has a hierarchical nature. Language could ride on such structures and then get better as cultural selection honed them.
GENES AND BRAINS FOR LEARNING COMPLEX SEQUENCES
FOXP2 codes for procedural and motor learning.
255 – Language and tools (manual actions) involve overlapping brain regions.
The differences seem trivial: language does auditory regions, tool use, motor regions. Brain regions once thought specific to grammar now turn out to be used for sequential, hierarchical procedures generally.
The spread of non-tonal languages like English and Spanish seems to have favored two newer genes. We only use pitch to indicate mood or emphasis or feeling. Chinese don’t have them.
256 – Any baby can learn any language, TO BE CLEAR (he says), but it might be more difficult for some than others.
CULTURE, COOPERATION, AND
WHY ACTIONS SPEAK LOUDER THAN WORDS
People say language is THE Rubicon that separates us from other animals. There are problems with this view.
a) it underestimates how much cultural transmission and evolution can happen without language. Fire, info on dangerous animals, edible plants, cooking, died even social norms can happen without language.
b) language itself is a cultural artifact so it cannot cause culture.
c) Language can cause lying deception and exaggeration.
257 – If C is not addressed it would seriously limit language’s spread. If others are tricking me, I can ignore them and language will go away. So, language alone cannot be the big spur to human cooperation. Reputations were needed prior to language for it to take off and social norms against lying.
258 – This could have been countered by CREDs (Credibility Enhancing Displays). These explain why religious leaders take vows of poverty.
SUMMARY: 7 points
1) Languages are packages of cultural adaptations. They are thus subject to cultural evolution.
2) They will evolve to be learnable.
3) The size and interconnectedness of populations sustains larger vocabularies.
4) Modern languages and the ones they evolved from likely look quite different.
5) It endows us with new abilities.
6) They create intense genetic pressures.
7) Understanding language’s evolution requires putting it in the broader context of culture-gene coevolution of tools, skills, and social norms.
ENCULTURATED BRAINS AND HONORABLE HORMONES
260 - To read these words you are using a culturally constructed network centered in the left ventral occipital temporal region of your brain. If damaged, people lose their literacy, but retain other cognitive function.
The more you read the more specialized your brain is for reading.
261 – The letter box, where we see letters, is between face recognition and one focused on objects. It also thickens the corpus callosum.
The rewiring gives people: 1) longer verbal memories; 2) broader brain activation to spoken words; 3) a greater awareness of the sounds that make up words.
Skilled readers, though, are often worse at recognizing faces. In fact, asymmetrical face recognition mechanisms being on the right side of the brain, may be because reading pushed it there.
These are biological modifications, but not genetic ones. They come from thousands of years of cultural evolution.
262 – They seem to take advantage of dedicated sensitive brain regions, such as for recognizing faces.
263 – This is a kind of biological evolution, it just isn’t genetic.
WINE, MEN AND SONG
265 – If one sort of female is rated high by someone, then men tend to generalize the esteemed characteristics. Average ratings from others are important.
266 – Brain scans show people enjoy wine more when it is told it is expensive. This is funny as Americans with no training actually like cheaper wines.
MODIFYING THE HIPPOCAMPUS BY DRIVING IN LONDON
267 – Cabbies have better special memories, but are worse at recognizing complex geometric figures. Our brains are specialized for the the skills and demands of the worlds which we inhabit.
268 – This realization informs the emerging field of cultural neuroscience.
Educated westerners have an inclination for and are good at focusing on isolated objects and abstracting properties.
Asians are better at guessing the relative length of a line segment.
This requires more effort in westerners.
269 – He stresses that, “In this case, however, genes play at most a tiny role, and I suspect no role.” Acculturated Asians seemed to take western brain patterns.
271 – Here he goes over the Culture of Honor study
where those from the South have more stress hormones at being bumped. Recently this has been used to argue
why the South has twice the murder rate of the North.
The South had deep immigration from Scotch – Irish. But these parts of Britain have no higher rates of crime.
272 – He thinks this only reflects weak institutions in the South. He speaks not of epigenetics. And, does not consider super fast genetic evolution could have happened.
CHEMICALLY INERT BUT BIOLOGICALLY ACTIVE
273 – Placebos are effective. Drugs are more effective if you believe in them. Placebos for ulcers work twice as well in Germany than Denmark.
274 – People who take their medicine get better, but it isn’t only due to the medicine.
275 – Self – regulation, which can be improved through religious rituals, can extend your life.
IT HURTS SO GOOD
276 – Cultural learning reduces pain. And, electroskin galvanizing tests show it does not just do so subjectively. It actually reduces physiological reactions to shock.
THE BIOLOGICAL POWER OF WITCHCRAFT AND ASTROLOGY
A ‘nocebo’ is the opposite of a placebo. It is when the patient has an expectation of getting worse.
Sorcery and the ‘evil eye’ go from Chile to the Middle East. Those holding witchcraft beliefs could induce illness in their bodies.
278 – Chinese – Americans who believe they have a birth year that predisposes them to illness die earlier.
WHEN WE CROSSED THE RUBICON
280 – There is no reason to believe that when we became a cultural species was any particular moment.
“With low quality imitative abilities, error – prone copying, social intolerance, (281) and little or not teaching, accumulating and sustaining cultural adaptations would have been very delicate in the early days. So when were the early days?”
4 Million years ago, we walked on two legs with a brain somewhat larger than a chimpanzee. These were the Australopiths.
282 – They had larger brains than any ape. They stood so could carry tools.
About 3.4 million years ago, we get stone tools to scrabe meat off a cow / horse type deal. Probably, australopith, the thumb had lengthened and the fingertips widened. Muscle attachments show a stronger thumb.
283 – 2.6 million years ago the first stone tools appear. Not just stones used as tools, but stones crafted. Apes cannot make tools this complicated.
284 – 285 There is evidence relative to the beginnings of cumulative cultural evolution.
Interestingly, it says 1.8 million years ago we have Homo erectus in Asia and the caucuses.
2.3 million years ago we see some development in Broca’s area.
2 million years ago we get tools made by right hand folks (90% were right handed).
1.7 million years ago we get a narrowing of the pelvis and smaller teeth.
288 – These tools, (see 283 above) would have been very hard to figure out individually. So they might have been cumulative cultural products.
They could, though, be reinvented occasionally and spread locally.
289 – There is a back and forth of progress. But, improvements are fuzzy from 1.9 – 2.6 million years ago.
1.8 million years ago is the genesis of what he is simply calling Homo Erectus in Asia, Africa and Europe.
Their barrel shaped rib cage like us. So this suggests a smaller guts to process food and so probably processed food.
290 – A good case could be made that Erectus had some control of fire and cooked. And there is good evidence by 800,000.
In Africa Homo Erectus emerges at the same time as new large stones. It takes modern humans hundred of hours to learn to process tools as they did.
The shoulder and writsts of Homo erectus changed to. This means good throwing ability. And people who practice are better throwers. People who don’t practice, like girls, don’t throw well. So practice is a tradition.
291 – Erectus had many adaptations for distance running. A large butt, narros hips, better heat loss from the head, and long legs.
292 – By 1.4 million years ago, the middle finger had lengthened to look like ours which gives a precision grip and reinforces the whole hand and wrist.
293 – About 900,000 years ago, the pace of environmental fluctuations picked up.
In Gesher Benot Ya’aqov, about 750,000 years ago, we have extensive remains of hearths and stone tool manufacturing and food processing.
294 – By 300,000 years ago, the brain had expanded so much that we can call it a new species. Homo erectus becomes Homo heidelbergensis. Again, Gesher Benot Yaaqov provides evidence.
295 – Heiidelbergensis seems to have had ears calibrated like humans to speech sounds. Tools drop in and out of the record and don’t make an enduring appearance until 100,000 years ago. But this is what you’d expect from delicate cultural learning.
297 – Why us and not other species? Well, the riddle may come from the ‘start – up problem.’
Cultural evolution and bigger brains can facilitate a lot. But, at first there won’t be much to acquire. What there is will be so simple, you can learn it alone.
Natural selection would then invest in increasing individual learning abilities. This would increase social learning by some degree as a by- product.
TWO INTERTWINED PATHWAYS CREATE A BRIDGE
If we could expand the cultural repertoire without expanding brain size, this would be an onramp. Or, we could also lower the cost of larger brains.
LARGE, GROUND-DWELLING PRIMATES
PRODUCE BIGGER CULTURAL ACCUMULATIONS
299 – On the ground individuals can have both hands free. Also, on the ground you have access to more individuals, (not blocked by trees).
Captive orangutans spend more time on the ground in captivity than they do in wild. And, they make more complicated tools and use them more.
300 – A move out of the trees was underway by 5 million years ago. By 4.4 million definitely, but with smaller brains.
PREDATION FAVORS LARGER GROUPS,
WHICH FAVOR GREATER CULTURAL ACCUMULATIONS
The number and variety of large carnivores was then about twice the level of today.
302 – Faced with increased threats, mammals often respond by forming larger groups. Apes, disperse under such pressures. If we resisted this, it would have given us access to many more individuals.
SHIFTING ENVIRONMENTAL CONDITIONS FAVOR MORE SOCIAL LEARNING
Math models show unstable environments create more social learning compared to individual learning. About 3 million years ago instability increased and this continued till about 10,000 years ago.
303 - This would have helped us and many others, so it doesn’t – alone – say ‘why us.’
THE SOCIALITY – CARE PATHWAY
The obstacle is that if we get more cultural repertoires, we need bigger brains. This means more time in gestation and lactation. So mom needs more calories and spacing between births.
Chimp moms nurse for 5 – 6 years and so need that much time between births. Needing more years to mature, requires longer generations. This makes us more vulnerable to environmental and other sources of ruin.
The work around? Others help mom.
PAIR-BONDING, SOCIAL LEARNING, AND FAMILIES
304 – I n many species males make dominance via violence. And, this predicts long-term fitness. But, the payoff declines as group size grows. It means fighting off more and more males and keep track of more females.
The large Ngogo chimp group seems to be hedging towards pairs.
305 – In chimps females migrate into other groups. They get foraging tips from a male elder, (who got it from his mother). So the male has local cultural knowledge to pass on.
Chimps use, ‘who is hanging around mom’ to sort of intuit who is family.
306 – Sons aren’t so interested in mothers in chimp culture. The hangs around mom rule can also hip men to who is mother of offspring. Younger brother may then hang around older brother and we have the start of families.
Concealing ovulation makes men need to be around ‘their women’ more consistently.
307 – Social learning leads to cultural learning, which increases the amoung of social learning.
HELP FOR MOTHER AND THE DIVISION OF INFORMATION
307 – Alloparent care refers to situations in which individuals besides mom help care for offspring.
308 – A search of 8 small-scale communities showed mothers do only about half of the childcare. Ape mothers do 100%. Of course, alloparenting allows for cultural transmission. And, families of prestige may get even more alloparenting.
309 – In one society a small girl was scolded, till nearly ostracized, for not helping a mother with her baby. This norm is why more distantly related and unrelated folk do 20 – 30 % of child care in small-scale societies.
310 – social learning and pair-bonding and alloparenting may explain the gendered division of labor as a division of information.
Gene culture co-evolution will mean that eventually girls will be more interested in girl stuff, etc. And, we already saw that girls pay more attention to women. Boys like projectiles – 6 month old boy infants are more into patting balloons than girl infants.
THE BEGINNING OF TRIBES
311 – When women migrate to another tribe, this facilitates the flow of information. It may, also, eventually reduce between group tensions and start a larger group. So waterholes, may be able to be shared.
312 – So there is an intersection of the know-how and sociality pathways.
WHY LIVING APES HAVEN’T CROSSED THE RUBICON
Gorillas pair bond, but live in single-family polygamous units. They are too small for cultural evolution.
313 – Chimps really only have access to mom as a role model (90% of the time).
Alloparenting allows mom to have more children. This allows a massive increase in brains, increasingly selected for their cultural learning abilities.
A NEW KIND OF ANIMAL
314 – Major transitions happen when less complex forms of life combine to make more complex forms. For example, individual molecules join to become chromosomes. Our transition represents a new kind of animal.
315 – The standard picture is that 50,000 years ago, or so, genetic evolution stops and cultural evolution takes over. The rest is only history. The flow is genes, make psychology, which makes culture. Culture is then recent.
316 – These fail to recognize that cultural evolution has been the central force driving human genetic evolution for hundreds of thousands of years. [italics in the original].
Many aspects of our physiology and anatomy make sense only as genetically evolved responses to selective pressure created by cultural evolution.
WHY ARE HUMANS UNIQUE?
317 – Having crossed the Rubicon, we can’t go back.
318 – Even hunter gatherers are dependent on large amounts of cultural knowledge. And most human societies have bodies that make group-level decisions. We’re being gradually shaped into superorganisms.
WHY ARE HUMANS SO COOPERATIVE COMPARED TO OTHER ANIMALS?
319 – Natural selection shaped our psychology to make us docile, ashamed at norm violations, and adept at acquiring social norms. This is the process of self domestication, where genes must survive in a world of pro-social norms.
These include constructed norms that harness our kin psychology, pair-bonding instincts, and incest inversion to weave expanded kinship networks that include affinal relatives, and classificatory brothers and sisters.
320 – Threats from reputation damage now loom large. But for flexibility, we see different norms upheld and cultural diversity.
WHY DO WE SEEM SO SMART COMPARED TO OTHER ANIMALS?
321 – If we used the same scale, the average IQ in 1815 would be below 70.
322 – Individual genius is no longer the driver. Many discoveries are made simultaneously by several folks.
Norms and rituals make this ‘group’ possible. Tribes have culturally constructed relationships, not genealogical, to make their larger groups.
323 – We can reverse engineer our tools and this is the beginning of a causal model. The causal model didn’t cause fancy tools; it is an after thought to improve cultural transmission. The tools drove causal thinking.
The number of folks in the pyramid determines how high the pinnacle.
IS ALL THIS STILL GOING ON?
Yes, it has only accelerated.
324 – We now have institutions that run our groups, like laws and courts. And religious high-gods help too. These required Credibility Enhancing Displays (CREDs).
Social norms, like a single wife, emerged. Monogamous marriage may have increased because it suppressed male-male competition within societies, which reduced crime, violence and rape, while increasing infant health and male investment in children.
Larger societies had more technology.
325 – So 1500, AD, Eurasia had the largest tool kit and New Guinea not so much. And, now interconnectedness is growing it. Especially as we interconnect people at the knowledge frontier.
It’s not the individuals, but the number of them.
326 – The internet is only hampered in joining us by language barriers. Can prosocial norms be maintained there?
HOW DOES THIS CHANGE HOW WE STUDY HISTORY, PSYCHOLOGY
ECONOMICS, AND ANTHROPOLOGY?
327 – First, we must realize that, even if not genetically different, “people who experience very different institutions, technologies, languages and religions, just to name a few domains, will be psychologically and biologically different.”
Growing up in different cultures alters our ‘visual perception, fairness motivations, patience, responses to honor threats, analytic thinking, tendency to cheat, frame dependence, overconfidence, and endowment biases.”
Men’s testosterone drops when they are married in a monogamous society. In polygamous societies, many poor men cannot get married, because the high-status men may have 3 wives, so their crime rates go up. And, married men in polygamous societies may still be chasing new brides. So their testosterone may not go down.
What has reading done to brains?
CAN THIS HELP US BUILD STUFF?
328 – We thought Iraqis would just adopt our culture like an adopted car.
Aiming to eradicate social evils, public health specialists have long stressed “education.” Norms are more important than facts.
329 – 8 Insights from this book:
1) We are adaptive cultural learners who look to cues of prestige, sex, dialect, and ethnicity to attend to items like food, sex, danger, and norm violations, especially under stress.
2) (330) But we aren’t suckers. We demand Credibility Enhancing Displays (CREDs) to avoid being cheated and turn martyrs into cultural transmitters.
3) We seek status, but that which garners prestige changes.
4) Social norms often come with internalized motivations and ways of seeing the world.
5) We are biased towards certain norms. For example, loving strangers is a harder sell than loving your children. Rituals also tap into our psychology.
6) Innovation depends on the spread of collective brains, which social norms, institutions and psychologies spread.
7) Societies have different norms, institutions, languages, etc. They do not readily adopt other’s formal institutions without changing them.
8) We are bad at intentionally designing institutions. Until we’re better, we should do ‘variation and compete’ to get good institutions.