Pattern (IMAGE) Rissho University Caption A typical pattern of time evolution of norms' frequencies and the cooperation rate generated by 'dividualism': Stern-Judging becomes extinct when cooperation has been achieved. The more tolerant a norm is, the higher the frequency of the normbecomes in the population. Credit Hitoshi Yamamoto Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.