时差N小时:有用的阑尾

Dear a moment of science: I used to think that theappendix is useless, but now I'm hearing that the appendix actually does serve a purpose. So,which is it?

亲爱的科学时刻：以前我觉得阑尾是无用的，但最近我听说阑尾实际上也有用途。那么，哪种说法是对的。

Yale: Great question. It's true that for a long time scientists thought that the appendix didn'treally serve a purpose. But a few years ago a study showed that the appendix in fact plays animportant role. It's a sort of hangout for useful bacteria needed to help us digest food. After abad case of diarrhea, when most of the bacteria in our guts is washed out, the appendix sendsa fresh batch in to take over.

雅艾尔：这个问题好。的确，很长时间以来，科学家们认为阑尾没有什么用途。但几年前的一项研究显示阑尾其实扮演着重要的角色。消化道里有益细菌是阑尾的常客。腹泻严重时，我们体内大多数细菌会被冲走，阑尾则为消化道输送一批新的消化细菌。

Don: Right. And not only that, but a more recent study has found that the appendix has along and storied history. It's been around in animals including kangaroos, rodents and apes forat least eighty million years. In other words, it's fairly common in nature.

唐：对。不仅如此，一项近期的研究发现阑尾有一段漫长而颇负盛名的历史。在袋鼠、啃齿动物以及猿等动物身上流传了至少八千万年。换句话说，在自然界中这是很普遍存在的。

Yale: Now, it's true that in developed countries with modern sanitation, the human appendixhas less to do than it once did. In those places, where diarrhea isn't a major problem, theappendix isn't called upon all the time to do its thing. That's why when people in the UnitedStates and other developed countries have their appendix removed, they don't seem to missit.

雅艾尔：现在，发达国家具有现代的卫生设备，人类阑尾的作用就大不如从前了。在这些地区，腹泻并不是严重的问题，阑尾并不总是能发挥作用。这就是为什么在美国和其它发达城市，人们会切除阑尾，且并不留念它。

Don: But in places where drinking water and sanitation aren't as safe, the appendix plays alarger role in keeping people healthy.

唐：但是在那些饮水和卫生条件差的地方，阑尾在保护人类健康方面起着重要的作用。