Ch. 13 Social Interaction

Cooperation

Behavior where individuals integrate activities to achieve goals that increase inclusive fitness of both

What 3 main contexts is cooperation observed in

• Male-female

• parent-offspring

• group cohesion

______ altruism does not exist

Indiscriminate

The risk of cheating is always present. How do organisms minimize cheating?

Limit cooperation to known individuals; Honest evidence of need by recipients, and ability to provide by donors

Indirect benefits

Cooperators sufficiently genetically related that any inequities in direct benefits or costs are compensated for by indirect benefits through genetic effects

Kin altruism

an evolutionary strategy where individuals risk their own safety or reproductive success to benefit genetic relatives

Greenbeard altruism

an evolutionary theory where a gene causes a recognizable trait (the "green beard"), permits recognition of that trait in others, and triggers preferential altruistic behavior toward those individuals

Direct Benefits

Ignores genetic similarities; Assumes all parties get a net direct benefit from cooperating

Mutualism

direct benefit models; a type of symbiotic relationship where two different species interact, and both partners benefit from the association, increasing their survival or reproduction

Bi-product Mutualism

donor behaves selfishly, and inadvertently benefits the recipient

Investment Mutualism

specialized concept where one individual incurs a cost—an "investment"—to send a signal or provide a service that benefits both itself and the receiver, leading to a long-term, mutually beneficial relationship

Mutualism consider a task with a fixed _____, and a fixed _____-

investment (cost); benefit

Risk in mutualism

Will cost be shared equally between cooperating members? Actors and cheaters get same benefit...so tempting to cheat.

Synergism

organisms gain greater benefits through cooperation than they would through the sum of their individual efforts

In Synergism, total benefit is _____, so….

asymptotic ; so some intermediate number of individuals maximizes total benefit

Reciprocity

Donor expends costs now, with expectation of payback from recipient later(think bat example)

____ ESS is never used for cooperation, instead you get…

Pure; Stable mixture of actors/cheater, Unstable systems, cycling through different weightings of the two strategies

In reciprocity _____ must (typically exceed ____

Benefit; cost

In reciprocity, _____ _____ must occur to provide net benefit to participants

sufficient interactions

Regardless of ESS, individuals must be highly selective when choosing partners to cooperate with. ______ of appropriate partners is critical.

Recognition

To aid in recognition, individuals may use:

• Spatial location

• Familiarity

• Phenotype matching

Recognition – Spatial Location

a cognitive process that enables the identification and memory of where objects or events are located within an environment

Spatial Location is useful if

odds are good that only the target will be in a location

Recognition – Familiarity

Learning specific characteristics of other individuals or groups like complex signature scents, calls, or badges.

In familiarity _____ _____ may lead to errors.
Cheaters/parasites may capitalize on this.

Memory saturation

Recognition – Phenotype matching

Identifying genetic similarity