My guess is that there's nothing quite that specific in our evolutionary past. But rather, if you're looking for an evolutionary explanation, you might say that most organisms are neo-phobic -- that is, they're a little scared of stuff that's new and different.
我的猜测是， 从人类的进化史上看 从来没有任何东西是特定的。 然而，如果你去寻找 一个进化论的解释，你也许会说 绝大多数物种都有一种“恐新症” ——就是说，他们害怕 新的、不一样的东西。