REPUTATION
WHY DO PEOPLE CARE ABOUT REPUTATION? Reputation: evaluation made by other people with regard to socially desirable or undesirable behaviors. Why are people so sensitive to social evaluation? Can we understand reputation from an evolutionary perspective?
COOPERATION & ALTRUISM psychological altruism a motivational state with the goal of increasing another s welfare Ethical altruism One has a moral obligation to promote the happiness/well-being of others even at the expense of one s own happiness/well-being biological/evolutionary altruism a social behavior counts as altruistic if it reduces the fitness of the organism performing the behavior, but boosts the fitness of the recipient of the behavior.
IS ALTRUISM AN EVOLUTIONARY DEAD END? Selfish Gene theory (Dawkins) Evolutionary Game theory Game theory with fitness rewards and punishments that then iterate over generations Fundamental findings: altruism is an evolutionary unstable strategy. A population of altruists can be invaded by selfish agents, who then drive down the proportion of altruists to 0
SO, HOW DOES COOPERATION EVOLVE? Forms of cooperation Mutualism both agents simultaneously receive benefit kin selection (Hamilton 1964) reciprocal altruism (Trivers 1971) Other forms of reciprocity (indirect, strong) Evolutionary Mechanisms Social selection Sexual selection Group Selection selection operates at the level of the group
LEVELS OF SELECTION
SOCIAL SELECTION Sexual selection refers to the subset of social competition in which the resource at stake is mates. And social selection is differential reproductive success (ultimately, differential gene replication) due to differential success in social competition, whatever the resource at stake. (West-Eberhard, 1979, p.158 )
NESSE Only humans, however, get major fitness benefits from exchanging multiple different resources with many other individuals with time delays that make defection a potential problem. Humans are, consequently, exquisitely sensitive to social rejection. Once fitness is significantly influenced by one s desirability as a social partner, individuals with the best displays of resources and generosity will get increasing advantages. What kinds of traits should we expect social selection to shape? It should shape traits that make an individual preferred as a social partner, including (a) high levels of resources (health, vigor, personal skills, powerful allies, status, territory, and other resources), (b) tendencies to share those resources reliably and selectively with relationship partners, (c) accurate intuitions about what others are seeking in a partner, and (d) strong motivations to please partners and other in-group members.
NESSE Social selection offers an explanation for the central role of display of resources and generosity in every culture. From potlatch ceremonies to conspicuous consumption (Veblen, 1899), they are often referred to as status displays, but they may increase fitness by attracting and keeping the best possible social partners. social selection shapes extreme vigilance about how others are judging you. This is not only to preserve reputation to maximize personal gain, but also because selection has directly shaped intense wishes to please others by acting in whatever ways will make one a preferred partner.
SEXUAL SELECTION Competition for reproduction Intersexual selection attractive to opposite sex (mate choice) Intrasexual selection (intimidating, defeating same-sex rivals) Sexual strategies: Short-term: good genes Long-term: genes, parenting, partners
SOCIAL SELECTION AND SIGNALING costly signaling a signal is so costly that only high health, high status, high condition animals can afford to produce it, the signal can remain evolutionarily reliable
FACIAL SIGNALS
FACIAL-WIDTH RATIO
BEHAVIORAL SIGNALING Observable behaviors have a signaling role Understanding of social norms Gifts mechanism for converting cash into reputation Dress historically highly regulated (Sumptuary Laws)
MORAL VIRTUES AS COSTLY SIGNALS Apart from physical appearance and social status, which traits most excite our romantic impulses? People often fall in love based on positive assessments of each other s generosity, kindness, honesty, courage, social sensitivity, political idealism, intellectual integrity, empathy to children, respectfulness to parents, or loyalty to friends.
ATTRACTIVE MORAL VIRTUES kindness: emotional responsiveness to the needs of others empathy: lovingness, affection, fondness, commitment, forgivingness, trust, and perspective-taking niceness: agreeableness and nonviolence honesty heroism
COURTSHIP AS MORAL OBSTACLE COURSE Courtship generosity conspicuous display
MORAL BEHAVIOR Morality through mate-choice model also has distinctive strengths and weaknesses that can explain some moral virtues especially those that show high sexual attractiveness, assortative mating, phenotypic and genetic variance, heritability, condition-dependent costs, conspicuous display in courtship settings, and young adult age peaks in display not to suggest that human morality is sexually motivated at the level of individual behavior. Evolutionary functions do not equal proximate motivations
WHAT ONLINE AD REALLY MEANS? SF, 26, seeks kind, generous, romantic, honest man single female, 26, seeks a healthy male of breeding age with a minimal number of personality disorders that would impair efficient coordination and parenting in a sustained sexual relationship, and a minimal number of deleterious mutations on the thousands of genes that influence the development of brain systems for costly, conspicuous, altruistic displays of moral virtue.
POTENTIAL SOURCES OF EVIDENCE Positive heritability Conspicuous courtship display Condition-dependent cost & positive correlations with other fitness indicators Comorbidity among vices & brain abnormalities Higher trait variance in males Young adult peak in trait expression
SIGNALING: ACTS VS. TRAITS Utilitarianism, deontology both focus on acts (decision rules) rather than underlying traits. Does signaling support Aristotle s notion of moral traits (virtues)? Evidence: perception of moral character
DELGADO ET AL. 3 players: Praiseworthy: English grad student and volunteer inner-city teacher who rescued a friend from a fire Negative: business grad student who has been arrested for trying to steal tiles of the space shuttle Columbia on an Internet site. Neutral: engineering students who narrowly missed a doomed flight but no moral information. In fact, all three were fictive and played at the same reinforcement rate.
The Trust Game Why study Trust? - Important in social interaction - Often trust is in contradiction with game theory irrational behavior - little is known about the neural circuitry of trust How to study Trust? - Interacting subjects in a dynamic social exchange - Unrestricted choice rich behavior - Large sample size - Synchronized brain activity
INVESTOR / TRUSTEE TASK
FMRI IMPLEMENTATION n = 140; players play for real money
TASK DESIGN
CAUDATE NUCLEUS
BRANDED CLOTHING Experimental manipulation branded vs. unbranded shirt Enhanced status perceptions Higher compliance (52.2% of the occasions, compared to 13.6% in the no-label condition) Social preferences (video job interview) branded subject more suitable for job, higher wage Charity donations (higher donations when solicitor wore branded shirt) Higher transfers in dictator game