Länk - Varför sker avchimpanisering?
This behavior of intentionally gathering together and going out to kill members of our own species is an extremely rare behavior. Humans do it. Chimps do it. There is some evidence that wolves and hyenas do it. But it's pretty much a human and chimp innovation. You have a very intelligent animal and a social animal. And when you're a social animal, all of the evolutionary pressures are toward living in a group. There are hierarchies. There are mechanisms for resolving disputes in nonlethal ways. That can all be summed up under empathy. But humans and chimpanzees, when they are fighting an out-group, have the ability to turn off the empathy. By turning that off, you dehumanize the enemy or dechimpize the enemy.
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