L7 Cooperation

Who introduced the payoff matrix?

Hamilton

What is the payoff matrix, and how it does it illustrate the cooperation problem

it categorises social interactions (actor, recipient) into mutualism (+, +), selfishness (+, -), altruism (-, +) and site (-, -)

Considering the payoff matrix, why should altruism “not evolve”, what is the downside of it?

the actor suffers a fitness cost while benefitting others, reducing own reproductive success

What individuals undermine cooperation

free riders

What is the free-rider problem in cooperation?

individuals who exploit cooperative benefits without contributing

Why does mutualism still face the free-rider problem, since both parties benefit?

individuals may attempt to minimize their own costs while maximizing benefits.

What is kin selection?

A mechanism where individuals help relatives to increase their inclusive fitness.

Who proposed inclusive fitness theory?

W.D. Hamilton

What is inclusive fitness?

the total fitness/genetic success of an individual’s genes

How to calculate inclusive fitness?

direct fitness (personal reproduction) + indirect fitness (helping relatives reproduce also pass on own genes)

What is Hamilton’s rule?

the analysis for altruistic behaviour as an act has a cost for the actor and benefits for the recipients

When does altruism evolve, according to Hamilton’s rule (equation)

c < r x b, where c = cost to actor, r = relatedness, b = benefit to recipient.

What does r represent in Hamilton’s rule?

the probability two individuals share an allele by descent

What is the “green beard effect” (though it is rare)?

Genes produce a trait, recognition of that trait, and altruism toward bearers of the trait.

What is the genetic relatedness between siblings?

Approximately r = 0.5.

Why is kin selection insufficient for explaining cooperation in large human societies?

Because many interactions occur between unrelated individuals (kind to nonkin).

Functional significance of kin selection in cooperation?

Promotes altruism toward relatives

According to natural selection, who are individuals expected to behave kindly towards

relatives, promote genetic selfishness

7 reasons why we are kind to nonkin

reciprocal altruism, mutualism, indirect reciprocity, generalised reciprocity, negative reciprocity, strong reciprocity, cultural group selection

What is reciprocal altruism, according to Trivers

direct form of reciprocity, individuals help others with the expectation that the favour will be returned in the future

What are 3 conditions required for reciprocal altruism?

Frequent interactions, ability to recognise individuals, and contingent behaviour.

What is mutualism?

Immediate benefits to both individuals without delay or reciprocity.

Why might mutualism be mistaken for altruism?

Because both parties benefit, but motives may be selfish.

What is indirect reciprocity?

expectation that the favour will be returned, not necessarily by the recipient but by someone else in the community

Two types of indirect reciprocity

downstream and upstream

What is downstream indirect reciprocity

helping others to build a reputation

What is upstream indirect reciprocity

helping others as a form of niceness

What is generalised reciprocity?

Altruism without expectation of return

What is negative reciprocity?

Punishment for harm done

What purpose does negative reciprocity fulfil

deters free-riders

What is strong reciprocity (two actions)?

Cooperate with others and punish non-cooperators

What is the benefit of strong reciprocity

helps to maintain social norms and cooperation within a group

What societies rely heavily on reciprocity?

Hunter-gatherers like !Kung San, Aché, Yanomamö.

What evolutionary human behaviour is reciprocity essential for

fair sharing of resources

What does the cultural group selection principle propose

that groups with altruistic tendencies will outperform less cooperative groups

What 3 cognitive demands does reciprocity impose?

Memory, recognition, and contingent decision-making.

What is game theory?

Mathematical framework for strategic decision-making in social interactions.

What is strategic decision-making

outcome for each participant depends on the choices of all involved

What are 2 processes involved in strategic decision making

rationality and utility

What is the assumption of rationality in game theory

that all players are rational and they know that all other players are rational

What is the assumption of utility in game theory

utility maximisation where players will consume a good to satisfy a desire

What is Nash equilibrium

a set of strategies where no player benefits from changing their strategy while the other players keep theirs unchanged

What is an Evolutionarily Stable Strategy (ESS)?

A strategy adopted by a population that is resistant to invasion by alternative strategies

What is the prisoner’s dilemma?

Game where defection yields greater personal short-term gain but mutual cooperation is the best collective outcome

What are the 4 outcomes (what is the acronym, when you fall?)?

TRPS

What is T in TRPS

temptation to defect (0 years, 20 years)

What is R in TRPS

reward for mutual cooperation (1 year, 1 year)

What is P in TRPS

punishment for mutual defection (5 years, 5 years)

What is S in TRPS

sucker’s payoff (20 years, 0 year)

What is the dilemma that involves a repeated game of game theory, allowing strategies to develop based on past interactions

IPD

What is IPD

Iterated Prisoner’s Dilemma

What is tit-for-tat (TFT) strategy?

Cooperate first, then copy opponent’s previous move; kind, retaliatory, forgiving.

What type of strategy is TFT

ESS

How does game theory apply to real-world cooperation problems?

E.g., climate change, resource sharing.

Functional significance of game theory?

Explains strategic behaviour and evolution of cooperation.

What is “cold cognition” in cooperation (+ 3 examples) ?

Reason-based processes

What is “hot cognition” in cooperation?

Emotion-driven processes influencing social decisions.

What role do emotions play in cooperation?

Serve as heuristics and “thermostats” to guide social behaviour

What is this table demonstrating

fortunes of others emotions

Positive feelings + positive feelings = ?

symhedonia

Positive feelings + negative feelings = ?

schadenfreude

Negative feelings + positive feelings = ?

jealousy

Negative feelings + negative feelings = ?

empathy

What is schadenfreude?

Positive feelings at others’ misfortune; can undermine cooperation.

What is symhedonia?

Positive feelings at others’ success; promotes prosociality.

What two feelings, according to the fortunes of others emotions, promote pro-social behaviour

empathy and symhedonia

What is the tragedy of the commons?

Overuse of shared resources leads to collective ruin

What is a public goods game?

An N-player prisoner’s dilemma testing cooperation in resource contribution.