The hundredth monkey effect is an esoteric idea claiming that a new behavior or idea is spread rapidly by unexplained means from one group to all related groups once a critical number of members of one group exhibit the new behavior or acknowledge the new idea. The behavior was said to propagate even to groups that are physically separated and have no apparent means of communicating with each other.[1]
Since it was first popularized, the effect has been discredited in many cases of research.[1][2][3][4][5] One of the primary factors in the spread of this concept is that many authors quote secondary, tertiary, or post-tertiary sources that have themselves misrepresented the original observations.[1]
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