Evolutionary Psychology: The New Science Of The Mind

My top 25 points:

1. Evolutionary psychology is the scientific study of the mind as a product of evolution. It seeks to understand how the human mind has been shaped by natural and sexual selection over thousands of generations.
2. Human nature is not a blank slate, but rather a set of evolved psychological mechanisms, designed by natural selection to solve the recurrent adaptive problems faced by our ancestors.
3. While natural selection is the primary factor in evolution, other causes of evolutionary change are sexual selection (mate preferences) and genetic drift (the favoring of a subset of the gene pool due to unique circumstances).
4. Classes of human problems

1. Survival and growth: reaching the stage at which the organism is capable of reproduction
2. Mating: selecting, attracting, and reproducing
3. Parenting: support the offspring until they can also reach the reproduction stage
4. Aiding genetic relatives: supporting those around us who carry our genes

5. Products of the evolutionary process

1. Adaptations: inherited and common to the whole population because they proved better at ensuring survival and/or reproduction (example: umbilical cord)
2. By-products: they have no functional designs and don’t (directly) solve any evolutionary problem (for example: belly button)
3. Noise: random effects produced by mutations and chance (for example: the shape of a person’s belly button)

6. Biggest misunderstandings about evolutionary psychology

1. Myth: Human behavior is genetically determined. Reality: genes interact with the environment
2. Myth: If it’s evolutionary, we cannot change it. Reality: we can change it, and one of the goals of studying evolutionary psychology is to gain more personal power over ourselves
3. Myth: Current mechanisms are optimally designed. Reality: no, they’re not. Evolution can be chaotic as it reacts to the environment.

7. We are aggressive in promoting and defending our interests; we can be and are brutal toward our kind. Among the more than 4,000 species of mammals, only two have been observed to form coalitions that kill conspecifics: chimpanzees and humans.
8. Sex and social dominance pervades our lives.
9. Humans evolved in groups and needed others to survive and reproduce. This prompted the evolution of motivations to seek the company of others, form social bonds, and curry the favor of others in the group.
10. Starting with Martin Seligman, for example, it became clear that humans can easily learn to develop certain types of fear, like snakes, but it’s difficult to make them develop other types of fear, like cars or electrical outlets. This shows the effect of evolution because snakes have been a threat since ancient times.
11. The Theory of Inclusive Fitness says an organism can also increase the reproduction of its genes by helping brothers, sisters, nieces, or nephews to survive and reproduce. One proven implication is that people will be more altruistic and helpful towards their kins.
12. Families are uncommon in the animal kingdom. Only 3% of mammals and birds form families. Two theories why families:
    1. families emerge when there is a lack of mating opportunities and
    2. families emerge when they can provide benefits to their offspring
13. Explanations for the puzzle of non-kin altruism

1. reciprocal altruism
2. indirect reciprocity: people benefit when others see them being altruists, and they gain a reputation as reciprocators
3. need-based transfer systems: risk pooling, a form of social insurance
4. costly signaling: increases reputation and status of the person showing altruism

14. Techniques to increase cooperation

1. Enlarge the shadow of the future: if people think you’ll be dealing with each other again, they’ll be more likely to cooperate
2. Teach reciprocity
3. Insist on no more than equity: when people know fairness is the goal, they’ll be more likely to trust and cooperate
4. Respond quickly to provocation: sends a signal you don’t tolerate exploitation
5. Cultivate a personal reputation as a reciprocator

15. There is mounting evidence that we evolved psychological adaptations to punish free-riders e.g. adaptations to enforce group norms, ostracizing those who violate social norms, status to those who contribute heavily to group goals, providing rewards to those who contribute etc.

16. How we tackled problems of survival

1. We dislike bitter and sour food because it’s likely to contain toxins
2. Neophobia: we have an innate dislike for new food because new food is potentially dangerous
3. Disgust is an evolved defense against disease
4. Adapted fears of life threats: snakes, spiders, heights, strangers.
5. Auditory bias: approaching sounds are perceived as louder than receding ones because of the greater danger of approaching threats
6. Darwinian medicine: fever, cough, sneezes probably shouldn’t be treated because they evolved to help us tackle diseases

17. Men tend to trust women more. This is because women have higher parental investment than men, so it is indeed more likely that women will take care of their own children.
18. Women tended to trust men less. Older men are far more likely than older women to remarry, and they might use their previous wife’s resources to attract a new mate and perhaps even start a new family.
19. Men in most cultures pursue extramarital affairs more than women do. Casual sex is a strategy more significant for men, than for women.
20. Three contexts for predicting parental behaviors

1. Paternity uncertainty (i.e. are the children mine?): This is one of the reasons why men generally invest less in children. Step-parents are more likely to beat, abuse, and ignore children who are not theirs. Women “remind” men that children look like them. Paternal grandparents invest less than maternal ones.
2. Alternative uses of the resources: Where can I get the biggest bang for the buck? My children’s or my sister’s? Nurturing or looking for another mate? Young women are more likely to kill their infants because they can produce more later on, under better conditions. Men high in status offer less parental care and ramp up their mating efforts.
3. Children’s ability to survive and reproduce: Ill and deformed children receive less help and are killed more often.

21. Why women adapted to be better nurturers

1. They are the primary caregivers
2. Better at decoding facial expressions, particularly negative ones
3. General reduction in risk-taking
4. Reduction in risk-taking when paired with babies

22. Why Parent-Child conflicts

1. Parents and children share 50% of their genes. But that also means they are 50% different, and that leads to potential conflict.
2. A child always gains in seeking more investment, while a parent might gain more by sharing their support among several children
3. Children will want more of their parent’s resources. Children seek to get more resources than their siblings.
4. Parents will want to give less than the child requests. Parents want to wean children sooner
5. Parents and offspring’s interests also diverge when it comes to the choice of mates. Children gain more from selecting a genetically superior partner because their offspring will inherit 50% of their genes. But parents only have 25% of their genes in common with their grandchildren, so they will gain more if their children select a partner that promotes their interest independently of genetic quality. Say, for example, a mate that will further their status and economic well-being.

23. Status, Prestige, and Social Dominance

1. Since the payoff for men is higher, men tend to seek status and prestige more than women do.
2. Service-for-prestige theory: Leaders provide key survival resources to followers by leading the group in more effective ways than anyone else could. In exchange, they receive social status and more mating opportunities.
3. Dominant men have more egoistic dominance acts, while dominant women have a higher incidence of prosocial dominance acts. Female dominance is more group-oriented.

24. Friendships

1. Men tend to prefer a larger number of less intimate friends and tend to spend less time nurturing their friendships.
2. In contrast to the psychological closeness and intimacy of women’s friendships, men tend to use friendships to achieve some common goal, such as cooperative hunting, cooperative defense, or coalitional warfare.

25. Summary

1. Buss criticizes the effort of cognitive psychology to hunt for “cognitive biases”, saying that they are not really biases but simply evolved shortcuts that work well for most of our evolution and most of our problems.
2. Evolutionary psychology should be the discipline that ties all the different branches of psychology together.