There’s a story we heard about a behavioral study in which five monkeys were put in a room with a banana hanging from the ceiling by a string. The only other thing in the room was a chair, which was
high enough that a monkey standing on the chair could reach the banana. There was also a way for the observing team to spray the monkeys with ice-cold water if they tried to stand on the chair to reach the banana.
A short time after the monkeys had been trying to get the banana and after all had been uncomfortably soaked, the monkeys started to get wise. They stopped climbing on the chair. The researchers would then remove one of the monkeys and bring a new one in. Whenever the new member would try to go for the banana, the others would prevent it from getting on the chair. After a period of rotations, all of the monkeys who were in the first round had been replaced, yet the remaining monkeys would prevent any newly introduced monkey from climbing on the chair, even though none had firsthand experience of being sprayed with the cold water.