The cognitive challenges of cooperation in human and nonhuman animals

Cooperation is widespread in nature, occurring in every taxa on Earth. Nevertheless, the contexts in which cooperation occurs — and the forms it takes — vary widely. In this Review, we outline how cooperation can evolve in nature and the cognition needed to support cooperation in different scenarios. We argue that the cognitively simplest forms of cooperation are those where an organism does not need to recognize interaction partners individually and that do not depend upon individuals keeping track of their partners’ actions and making contingent return investments. These simpler cooperative interactions occur most frequently among kin and among interdependent interaction partners and are relatively common in non-human animals. Conversely, cooperation involving individual recognition of interaction partners and where benefits depend upon contingent responses levy greater cognitive demands and occur in non-human animals only in limited contexts. The cognition needed to support cooperation in its multifaceted forms varies in different scenarios. In this Review, Melis and Raihani argue that whether individuals must recognize interaction partners and whether cooperative interactions need investment repayment can differentiate the cognitive demand posed.