Social psychology II
1. Evolutionary psychology
Altruism and natural selection: an evolutionary perspective on human nature
Natural selection and behaviour
- Evolutionary psychology: investigates the evolutionary origin of behaviour and
consequences of current psychological mechanisms
➔ Darwin: the origin of species = theory of natural selection → survival of the fittest: better
adaptation to environment → better fitness (= transferring next-generation genes)
➔ Primary interest: evolution of physical features
➔ Modern Darwinians:
• Primary interest: evolution of behaviour
• Evolutionary perspective on human nature:
➢ Universal characteristics: these successful characteristics provide such an
evolutionary advantage, that they spread throughout the population and become
typical for all mankind (bipedalism, universal psych features/characteristics)
Altruistic behaviour
- = helping others although it may be detrimental to your own fitness <->? Natural selection=
seemingly selfish process
- Explanation?: universal need to belong
➔ Social anxiety as an adaptation to prevent exclusion from group
Inclusive fitness and kinship
- = your personal reproductive success + the effects you have on the reproduction of your
genetic relatives, weighted by the degree of genetic relatedness
➔ Twins, parents, siblings, other relatives,…
- Better fitness (of next generation) by helping (genetic) relatives
➔ This implies:
• One takes risks for genetic relatives
• The higher the genetic relatedness, the higher the risk one takes dia10+11
➔ Conclusion:
• Who we help in different situations is predictable from an evolutionary perspective
• Strong evidence for the inclusive fitness theory
Reciprocal altruism
- Why do we help unrelated indiv?
- “I help you when you help me” only possible if:
➔ The person being helped can be recognized later
➔ Deceivers can be punished: cheaters are excluded
- In the end, helping increases fitness!
Sexual selection and sex differences in behaviour: an evolutionary perspective on sex
differences
Sexual selection and parental investment
- Sexual selection = the selection of, and different access to, sexual partners
- Forms of sexual selection/competition:
➔ Intrasexual competition: winner passes on more genes (male competition)
➔ Intersexual competition: choosing a mate based on their preferences (female choice)
- Parental investment theory (Trivers):
, ➔ Sexes differ in terms of time and effort spent in raising offspring (pregnancy, feeding,
protecting,…)
• Women invest more in raising offspring
• Men invest only in their seed
- Prediction: the sex that invests less in raising offspring will prefer having more (sexual)
partners dia16+17
- Prediction: the sex that invests less in raising offspring will be less selective in choosing
partners dia18+19
➔ Conclusion: men are less selective in choosing partners + choose more partners
Mating preferences
- Prediction:
➔ Men are looking for a partner who is young and physically attractive (~sign of fertility)
➔ Women are looking for a partner who can provide material support (good financial
prospect)
• Women long for a partner who is ambitious and industrious
➔ Confirmed in 37 cultures
• Structural powerlessness hypotheses: alt explanation for the difference: men are
associated with the role of breadwinner/money maker, women are financially
dependent on their man (gender roles)
• When women have a higher income/SES, they place even higher importance to
financial means/SES in men
- Both sexes want a physically attractive partner:
➔ waist to hip ratio dia26-28
➔ symmetry as a marker of “good genes”
• <-> fluctuating asymmetry: the degree to which an individual deviates from perfect
bilateral symmetry → shows “bad” genetic quality or development issues
Young men: risk and violence
- Cross-cultural observation: homicide by men on other men
➔ Evolutionary explanation: sexual competition
• Female choice (certainty about motherhood/larger parental investment)
• Men have to compete to gain “sexual access” (intrasexual competition among men)
→ more aggression, more risks dia30
Cuckoldry and jealousy
- Father: fundamental doubt about paternity
- Mother: no doubts about motherhood
- Cuckoldry = a man raising his wife’s child by another man
- Prediction: men and women will differ in the value they place on cues that trigger jealousy
➔ Men: more distressed by sexual infidelity
➔ Women: more distressed by emotional infidelity
➔ Confirmed, also with physiological measures
• Both sexes react distressed by both options!
• Forced choice: strong sex differences in line with the evolutionary expectations
- Women avoid loss of material help and assistance (emotional infidelity)
- Men avoid cuckoldry/responsibility for false fatherhood (sexual infidelity)
- Cross-cultural finding!
,2. Social interaction and dilemmas
How does a collective work?
Introduction
- Hobbes: “how are collectivities able to function if humans tend to be primarily concerned
with pursuing their self-interest?”
- Adam Smith: if everybody pursues self-interest, society will benefit as an unintended
consequence therefore conflicts between self-interest and collective interest do not exist ><
an everyday reality!
- Reward activates the orbito-frontal cortex and the ventral striatum (nucleus accumbens)
- Traditional theories:
➔ Assumption: humankind is rationally self-interested
➔ Early formulations of the game theory and social exchange theory
• Later on: human behaviour is guided by broader considerations than direct self-
interest alone
- Interdependence theory (Thibaut & Kelley):
➔ Interdependence structure:
• Situations in which personal outcomes are (partially or fully) determined by the
actions of others
Eg mixed-motive situations such as prisoner’s dilemma, social dilemma’s
➢ Conflict between personal goals and collective goals
➢ Selfish choice is usually most beneficial, although it brings a collective cost
Mixed motives
- Prisoner’s dilemma dia6-10
- Social dilemma’s:
➔ Social traps (resource dilemma): short-term advantages, but long-term costs
• Pollution, overfishing, global warming
➔ Social fences (public good dilemma): short-term costs, but long-term advantages
• Public healthcare public TV, public recreation & sporting facilities
• Indiv that don’t contribute still benefit (free riding)
➔ Indiv perspective (my gains and losses): cooperation is less likely in public good
dilemmas than in resource dilemmas
• Public good dilemma: immediate personal losses
• Resource dilemma: immediate (previous) benefits
➔ In-group perspective (our gains and losses): more cooperation in public good dilemmas
Structure of interdependence
- The interdependence structure of dilemmas is important
- Zero-sum situation: the gain for the one leads to an equal loss for the other (and vice versa)
➔ Strong conflict of interest! ; Strong tendency for conflict
- Win-win situation (both experts in different areas; both want to perform well)
➔ Strong tendency for cooperation
Beyond direct self-interest: transformation of situations
Transformation
- Interdependence theory (Kelley & Thibaut):
➔ Observation: the pursuit of direct (=immediate) self-interest often provides an
incomplete understanding of interpersonal behaviour
➔ Introduction of the concept “transformation”: going beyond direct self-interest, by
attaching importance to long-term outcomes, and/or outcomes of another person
, - Distinction:
➔ Given matrix: based on the pursuit of direct self-interest
➔ Effective matrix: takes into account broader preferences
- Dual-concern model: concerns about own outcomes and other’s outcomes
➔ Determine negotiation strategy:
• Problem-solving, inaction, yielding (=submissive), contending (=competing) dia15
Sources of transformation
- What leads indiv to go beyond direct self-interest?
- Interpersonal dispositions
➔ Social value orientation dia17
• Prosocial (=cooperative) orientation: seek to enhance joint outcomes and equality of
outcomes (self + other)
• Individualistic orientation: seek to enhance own (absolute) outcomes (self)
• Competitive orientation: seek to enhance own outcomes relative to others (self –
other)
• Prosocial indiv (cooperative orient):
➢ Make more cooperative choices (in prisoner dilemmas, social dilemmas,
negotiation situations, and social situations irl)
➢ Heterogeneous beliefs on humankind (some ppl are coop while others are
selfish)
➢ Elicit either coop or non-coop behaviour from others
• Anti-social indiv (individualistic and competitive orientation)
➢ Make more non-coop choices and behaviour
➢ Homogeneous beliefs on humankind (most ppl are selfish)
➢ Elicit non-coop behaviour from others, which strengthens their beliefs (cf self-
fulfilling prophecy)
• Mere ownership effect: ppl who own a good tend to evaluate it more positively/more
valuable than ppl who do not
➔ Trust, and by extension agreeableness
• = general belief in honesty and cooperative intentions of others cf facet of
agreeableness
➔ Long-term vision
➔ Other individual differences: cooperation in social dilemmas is higher when:
• Low in narcissism, low in envy, high in need to belong
➔ Where do these interpersonal dispositions come from?
• Nature: genetic influences, temperament
➢ Strong evidence that personality traits are heritable
➢ Meta-analysis: 40-55% of variance in adult personality traits is due to genetic
influences
• Nurture: social interaction experiences
➢ Importance of social learning processes: more prosocial orientation with
children from large families, more prosocial orientation with increasing age
- Priming
➔ Priming an interdependent mindset (“group, together,…”) promotes cooperation, BUT if
the person has a prosocial orientation, it is better to prime a self-mindset (“indiv
independent”) which can activate their existing prosocial values
➔ Priming competence or “smart” behaviour:
1. Evolutionary psychology
Altruism and natural selection: an evolutionary perspective on human nature
Natural selection and behaviour
- Evolutionary psychology: investigates the evolutionary origin of behaviour and
consequences of current psychological mechanisms
➔ Darwin: the origin of species = theory of natural selection → survival of the fittest: better
adaptation to environment → better fitness (= transferring next-generation genes)
➔ Primary interest: evolution of physical features
➔ Modern Darwinians:
• Primary interest: evolution of behaviour
• Evolutionary perspective on human nature:
➢ Universal characteristics: these successful characteristics provide such an
evolutionary advantage, that they spread throughout the population and become
typical for all mankind (bipedalism, universal psych features/characteristics)
Altruistic behaviour
- = helping others although it may be detrimental to your own fitness <->? Natural selection=
seemingly selfish process
- Explanation?: universal need to belong
➔ Social anxiety as an adaptation to prevent exclusion from group
Inclusive fitness and kinship
- = your personal reproductive success + the effects you have on the reproduction of your
genetic relatives, weighted by the degree of genetic relatedness
➔ Twins, parents, siblings, other relatives,…
- Better fitness (of next generation) by helping (genetic) relatives
➔ This implies:
• One takes risks for genetic relatives
• The higher the genetic relatedness, the higher the risk one takes dia10+11
➔ Conclusion:
• Who we help in different situations is predictable from an evolutionary perspective
• Strong evidence for the inclusive fitness theory
Reciprocal altruism
- Why do we help unrelated indiv?
- “I help you when you help me” only possible if:
➔ The person being helped can be recognized later
➔ Deceivers can be punished: cheaters are excluded
- In the end, helping increases fitness!
Sexual selection and sex differences in behaviour: an evolutionary perspective on sex
differences
Sexual selection and parental investment
- Sexual selection = the selection of, and different access to, sexual partners
- Forms of sexual selection/competition:
➔ Intrasexual competition: winner passes on more genes (male competition)
➔ Intersexual competition: choosing a mate based on their preferences (female choice)
- Parental investment theory (Trivers):
, ➔ Sexes differ in terms of time and effort spent in raising offspring (pregnancy, feeding,
protecting,…)
• Women invest more in raising offspring
• Men invest only in their seed
- Prediction: the sex that invests less in raising offspring will prefer having more (sexual)
partners dia16+17
- Prediction: the sex that invests less in raising offspring will be less selective in choosing
partners dia18+19
➔ Conclusion: men are less selective in choosing partners + choose more partners
Mating preferences
- Prediction:
➔ Men are looking for a partner who is young and physically attractive (~sign of fertility)
➔ Women are looking for a partner who can provide material support (good financial
prospect)
• Women long for a partner who is ambitious and industrious
➔ Confirmed in 37 cultures
• Structural powerlessness hypotheses: alt explanation for the difference: men are
associated with the role of breadwinner/money maker, women are financially
dependent on their man (gender roles)
• When women have a higher income/SES, they place even higher importance to
financial means/SES in men
- Both sexes want a physically attractive partner:
➔ waist to hip ratio dia26-28
➔ symmetry as a marker of “good genes”
• <-> fluctuating asymmetry: the degree to which an individual deviates from perfect
bilateral symmetry → shows “bad” genetic quality or development issues
Young men: risk and violence
- Cross-cultural observation: homicide by men on other men
➔ Evolutionary explanation: sexual competition
• Female choice (certainty about motherhood/larger parental investment)
• Men have to compete to gain “sexual access” (intrasexual competition among men)
→ more aggression, more risks dia30
Cuckoldry and jealousy
- Father: fundamental doubt about paternity
- Mother: no doubts about motherhood
- Cuckoldry = a man raising his wife’s child by another man
- Prediction: men and women will differ in the value they place on cues that trigger jealousy
➔ Men: more distressed by sexual infidelity
➔ Women: more distressed by emotional infidelity
➔ Confirmed, also with physiological measures
• Both sexes react distressed by both options!
• Forced choice: strong sex differences in line with the evolutionary expectations
- Women avoid loss of material help and assistance (emotional infidelity)
- Men avoid cuckoldry/responsibility for false fatherhood (sexual infidelity)
- Cross-cultural finding!
,2. Social interaction and dilemmas
How does a collective work?
Introduction
- Hobbes: “how are collectivities able to function if humans tend to be primarily concerned
with pursuing their self-interest?”
- Adam Smith: if everybody pursues self-interest, society will benefit as an unintended
consequence therefore conflicts between self-interest and collective interest do not exist ><
an everyday reality!
- Reward activates the orbito-frontal cortex and the ventral striatum (nucleus accumbens)
- Traditional theories:
➔ Assumption: humankind is rationally self-interested
➔ Early formulations of the game theory and social exchange theory
• Later on: human behaviour is guided by broader considerations than direct self-
interest alone
- Interdependence theory (Thibaut & Kelley):
➔ Interdependence structure:
• Situations in which personal outcomes are (partially or fully) determined by the
actions of others
Eg mixed-motive situations such as prisoner’s dilemma, social dilemma’s
➢ Conflict between personal goals and collective goals
➢ Selfish choice is usually most beneficial, although it brings a collective cost
Mixed motives
- Prisoner’s dilemma dia6-10
- Social dilemma’s:
➔ Social traps (resource dilemma): short-term advantages, but long-term costs
• Pollution, overfishing, global warming
➔ Social fences (public good dilemma): short-term costs, but long-term advantages
• Public healthcare public TV, public recreation & sporting facilities
• Indiv that don’t contribute still benefit (free riding)
➔ Indiv perspective (my gains and losses): cooperation is less likely in public good
dilemmas than in resource dilemmas
• Public good dilemma: immediate personal losses
• Resource dilemma: immediate (previous) benefits
➔ In-group perspective (our gains and losses): more cooperation in public good dilemmas
Structure of interdependence
- The interdependence structure of dilemmas is important
- Zero-sum situation: the gain for the one leads to an equal loss for the other (and vice versa)
➔ Strong conflict of interest! ; Strong tendency for conflict
- Win-win situation (both experts in different areas; both want to perform well)
➔ Strong tendency for cooperation
Beyond direct self-interest: transformation of situations
Transformation
- Interdependence theory (Kelley & Thibaut):
➔ Observation: the pursuit of direct (=immediate) self-interest often provides an
incomplete understanding of interpersonal behaviour
➔ Introduction of the concept “transformation”: going beyond direct self-interest, by
attaching importance to long-term outcomes, and/or outcomes of another person
, - Distinction:
➔ Given matrix: based on the pursuit of direct self-interest
➔ Effective matrix: takes into account broader preferences
- Dual-concern model: concerns about own outcomes and other’s outcomes
➔ Determine negotiation strategy:
• Problem-solving, inaction, yielding (=submissive), contending (=competing) dia15
Sources of transformation
- What leads indiv to go beyond direct self-interest?
- Interpersonal dispositions
➔ Social value orientation dia17
• Prosocial (=cooperative) orientation: seek to enhance joint outcomes and equality of
outcomes (self + other)
• Individualistic orientation: seek to enhance own (absolute) outcomes (self)
• Competitive orientation: seek to enhance own outcomes relative to others (self –
other)
• Prosocial indiv (cooperative orient):
➢ Make more cooperative choices (in prisoner dilemmas, social dilemmas,
negotiation situations, and social situations irl)
➢ Heterogeneous beliefs on humankind (some ppl are coop while others are
selfish)
➢ Elicit either coop or non-coop behaviour from others
• Anti-social indiv (individualistic and competitive orientation)
➢ Make more non-coop choices and behaviour
➢ Homogeneous beliefs on humankind (most ppl are selfish)
➢ Elicit non-coop behaviour from others, which strengthens their beliefs (cf self-
fulfilling prophecy)
• Mere ownership effect: ppl who own a good tend to evaluate it more positively/more
valuable than ppl who do not
➔ Trust, and by extension agreeableness
• = general belief in honesty and cooperative intentions of others cf facet of
agreeableness
➔ Long-term vision
➔ Other individual differences: cooperation in social dilemmas is higher when:
• Low in narcissism, low in envy, high in need to belong
➔ Where do these interpersonal dispositions come from?
• Nature: genetic influences, temperament
➢ Strong evidence that personality traits are heritable
➢ Meta-analysis: 40-55% of variance in adult personality traits is due to genetic
influences
• Nurture: social interaction experiences
➢ Importance of social learning processes: more prosocial orientation with
children from large families, more prosocial orientation with increasing age
- Priming
➔ Priming an interdependent mindset (“group, together,…”) promotes cooperation, BUT if
the person has a prosocial orientation, it is better to prime a self-mindset (“indiv
independent”) which can activate their existing prosocial values
➔ Priming competence or “smart” behaviour:
