evaluating mechanism that support evolution of human cooperation [guest lecture]

recipe for success

the three Cs: cooperation, cognition, culture

• human cooperation is unique

food sharing patterns in primates

• unresisted transfer of food

  • widespread sharing

  • sharing with adults

  • sharing with offspring

  • no sharing

cooperation

cooperation largely limited to group members → kin and reciprocating partners

food sharing in other animals

chimpanzees transfer food to others but majority of it can be viewed as tolerated theft

• widespread food sharing is absent

humans share food generously

forager food sharing is extremely generous

• hawkes: Hadza hunters retain no more of their hunting income than anyone else

• wood and marlowe: people retain less than majority of income

sexual division of labor

• men target less reliable foods and those foods are shared more widely

human cooperation is a puzzle

• evolutionary puzzle

• social behavior of humans poses significant evolutionary puzzle

• one of enduring puzzles in bio and social sciences is origin and persistence of intraspeciifc cooperation and altruism in humans

• dictator game

evolution of cooperation — a mismatch

cooperation often occurs between anonymous strangers because we evolved in small, stable grps of mostly relatives

• burnham and johnson: predict that human cooperative mechanisms include design features that modulate behavior in non anon and repeated environ and those mechnaims impact on empirical level of cooperation even in anon and final interactions

the hazda

• 1000 identify

• social organization

  • live in camps

• economic/political organization: sexual division of labor, high levels of egalitarianism

why study hazda:

• cooperative grp living

• absence of external monitoring and regulatory strcutures

• opportunities for free riding

why study cooperation in hazda:

• creation story: most do not know, few claimed haine created earth

• after death: few claimed there is afterlife, few hazda discussed heaven

hazda cooperation

public goods game

• 4 sticks of honey; keep or donate

• similarly cooperative people connected

• generous hazda not necessarily more popular

• cooperators live with other cooperators

  • clustering of them

• cooperators preferentially form ties with each other

• cooperative behavior is socially influence

• no evidence for partner choice for cooperation

• cooperators not more popular

• cooperation is not table (no behavioral persistence)

• weak agreement on rankings of cooperative character traits

humanc ooperative behavior flexible and affected be one’s local social enviornment