Ostracism or social exclusion may be used to discipline disagreeable members and promote cooperation. However, ostracism can also be an unintentional side effect of people joining up with individuals they have previously had good experiences with, where the ostracizers are oblivious of their acts.

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Ostracism or social exclusion may be used to discipline disagreeable members and promote cooperation. However, ostracism can also be an unintentional side effect of people joining up with individuals they have previously had good experiences with, where the ostracizers are oblivious of their acts.