Humans have richly interdependent social lives in which the outcomes of any single individual are strongly affected by the behaviors and outcomes of others in their social network [1]. In this context, humans cooperate to achieve objectives, resources, and outcomes that each individual could not achieve on their own. According to a biological perspective, humans cooperate to increase their ultimate outcome: reproductive fitness [2,3]. Due to the importance, intensity, and diversity of human cooperation (see Glossary) [4], this phenomenon has captured and sustained the attention of scientists across disciplines such as physics, biology, and the social sciences.
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