The  EVOLUTION  of  MORALITY IMAGE 24A   
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Concept/Content image scoring / cleaner wrasse (Labroides dimidiatus)
Information caption Organisms may benefit from social information, which allows them to regulate the occurrence of cheating. That is, they may learn how other individual organisms behave whether they are trustworthy cooperators, say and to act accordingly. For example, one small cleaner fish (Labroides dimidiatus) has a mutualism with large fish. The small fish eat parasites on the large fish. Occasionally, however, they "cheat" and feed on the host's mucus or nip a bit of its flesh. Other potential host fish (or "clients"), however, can observe such behavior. Such host fish show a preference for cleaner fish that are demonstrably "honest." Accordingly, cleaner fish cheat less when bystanders are present (Bshary and Grutter 2006). Social "eavesdropping" also seems to keep defection from cooperation in check.
Inquiry caption What other ways might organisms regulate the occurrence of cheating? Here is the small cleaner fish Labroides dimidiatus, which has a mutualism with large fish. The small fish eats parasites on the large fish. Occasionally they "cheat" and feed on the host's mucus or nip a bit of its flesh. Other potential host fish (or "clients"), however, can observe or "eavesdrop" on such behavior. How might this affect the dynamics of cheating and "honest" reciprocity?
In fact, host fish show a preference for cleaner fish that are demonstrably "honest." Accordingly, cleaner fish cheat less when bystanders are present (Bshary and Grutter 2006). The use of social information to evaluate other organisms' behavior patterns is known as image scoring.
Reputation can matter, it seems. Cooperation can be guided by status, or social information, rather than instances of direct reciprocity. Indirect reciprocity can evolve in a group with image scoring (Nowak and Sigmund 1998, 2005) and can also effectively solve the problem of the tragedy of the commons (Milinski et al 2002).
Target Concept: Organisms may benefit from social information.
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