众所周知，词汇是
red herring 分散注意力的东西
释义
If you say that something is a red herring, you mean that it is not important and it takes your attention away from the main subject or problem you are considering.
例句
The politicians often put out such red herrings to avoid the poverty issues.
GRE
As for the left-eyed and right-eyed flatfish, their difference, however striking, appears to be an evolutionary red herring.
至于比目鱼究竟是朝左还是朝右，不论其区别有多么令人吃惊，似乎仅仅是进化史上无关紧要的东西。