我们本以为这是再简单不过的进化选择了：当药物杀向全体细菌时，总有那么几个幸运儿，基因突变了，小命保住了，它们可以活下来继续繁殖下一代，而剩下的那些倒霉蛋就从此命归黄泉了。

The accepted scenario was a simple case of evolutionary selection. In a bacterial population exposed to a killer drug, a few lucky individuals might have a genetic mutation that kept them alive.

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