Nowak, "Five rules for the evolution of cooperation" (Science, via PubMed Central)
3 korrents from this paper
In plain words
Natural selection should only reward selfishness, yet five simple conditions let cooperation evolve: relatedness, chance of meeting again, knowing reputation, having few neighbors, or many small groups. These rules show when helpers can still spread and build new levels of organization from cells to human societies. It derives one clear benefit-cost rule for each of five known mechanisms and unifies them in a shared evolutionary payoff framework.
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