The human body is an amazing machine that is more complex than any man-made device ever created. While many of the functions it carries out require little explanation, some things it does are more complex. For the most part, people have no idea why their body does these things, but scientists and researchers have investigated them and came up with simple explanations for the baffling everyday functions of our body.
人体是一架不可思议的机器，它可比任何人类发明的机器都要复杂。人体的许多功能都不用过多解释，但有些东西却比你想象的要复杂得多。很多时候，人们并不知道身体为什么会有这样的反应，科学家和研究者对此进行了充分调查，最后对我们身体那些令人困惑的日常反应给出了简单的解释。

10.Hiccups
10.打嗝

Everyone has hiccuped at some point in their life. However, the involuntary action usually comes and goes relatively quickly for the vast majority of people, meaning it is more of a nuisance than anything else. Although for some, it can become something of an issue. Charles Osborne, for example, had the hiccups for 68 years.
人的一生总会在某些时刻打嗝。对绝大部分人来说，这种不自主的行为都是来得快，去得也快，也就是说，这只是一个小小的麻烦事而已。但是，对有些人来说，它可能会变成一个很大的问题。譬如，Charles Osborne已经打了68年的嗝。
Scientists have never been able to completely understand why people hiccup, but they have proposed several theories. One of the most recent ones comes from Daniel Howes. He suggests that the hiccups may have evolved as a way for infants to expel air from the stomach so that they can more effectively suckle milk. The contraction of the diaphragm causes suction that forces air out of the mouth, allowing the infant to burp itself. Howes points to the fact that only mammals—the only type of animals that suckle milk—get hiccups and that they are much more prevalent in the young.
即使是科学家也没有完全明白人们为什么会打嗝，但是他们还是提出了一些理论。最新的研究是由Daniel Howes发表的。他表示，婴儿打嗝是将胃里面的空气驱逐出来的一种方式，以使胃部更有效地吸收母乳。横膈膜（位于肺和胃之间的肌肉，呼吸时起作用)收缩时产生的压力迫使空气从嘴巴中出去，也就形成了婴儿的打嗝现象。Howes指出，只有哺乳动物——所有的动物中唯一需要喝奶的，才会打嗝，而且打嗝现象在幼年时更加普遍。

9.Appendix
9.阑尾

The appendix has long been considered an organ that does more harm than good. Its function was a mystery, and it has a tendency to cause serious health problems in a number of people. Appendicitis can lead to severe pain, fever, and even death if it is left untreated after the appendix bursts.
阑尾在很长的时间里都被认为是一个害多益少的器官。它的功能简直就是一个谜，对很多人来说，它时常会造成严重的健康问题。阑尾炎会产生剧烈的疼痛、发烧，如果疾病爆发后不经处理，还可能导致死亡。
In 2007, after years of research, researchers finally discovered what's believed to be the actual use of the appendix. Rather than simply being a leftover organ from our evolutionary past, it was an important part of the immune system. According to the research team, the appendix provides a safe haven for bacteria that is needed in the gut. When illness or diseases such as dysentery wipe out the bacteria in the gut, the organ allows the bacteria to reenter the digestive system. It essentially keeps a backup of bacteria needed for the immune system to function.
2007年，经过多年研究，科研人员最终发现阑尾是真的有其实际作用的。它并不是人类进化过程中退化的器官，而是免疫系统中非常重要的组成部分。根据团队的研究成果，阑尾为那些对人体肠道有益的微生物提供了一个安全的避风港。身体不适或患疾病时，比如说，腹泻使肠道中的微生物被洗劫一空时，阑尾就能使那些幸存的微生物重新进入消化系统中。本质上是它保证了免疫系统对微生物的需要能够及时得到补充。

8.Tickling
8.挠痒痒

Every person has experienced being tickled at some point. While it can be pleasant at times, it is usually something that people dislike and try to avoid. This has never stopped people from trying to tickle others, though. That fact, combined with the response to tickling, is something that has perplexed thinkers for thousands of years.
每个人都会在一些时候被挠痒痒。虽然有时候会是件挺好玩的事情，但更多时候人们非常不喜欢它，会尽量避免。但是，这也从来没有阻止人们去挠别人痒痒。结合人们被挠痒之后的反应，这件事难免让思想家们困惑了几千年。
Previously, it had been thought that the reaction might be a panic response, similar to that triggered by a spider crawling on you. But Christine Harris, following numerous experiments, has suggested a more complex answer. According to Harris, tickling may be a system designed to help develop combat skills.She points to the fact that close family members or friends usually carry out that tickling in much the same way as play fighting. It causes the recipient to convulse and try to break free as quickly as possible, teaching the victim how to get away from an attacker without actually causing them any harm. Meanwhile, the fact that the recipients laugh and smile when being tickled encourages the tickler to carry on the action and to do it more frequently. This increases the value of the action as it is reinforced multiple times.
之前，发痒被认为是人体对于恐惧的反应，就如同突然有一只蜘蛛在你身体上爬行，发痒便一触即发。但是，Christine Harris在做了大量的实验后提出了更加复杂的解释。根据他的想法，发痒可能是人体用来提高战斗能力的系统。她指出，当亲近的家人或朋友挠痒痒时，都差不多是以一种打斗游戏的方式来进行。这会使被挠痒的人身体不自主的震动，并想尽快挣脱束缚，这也就教会了受害者们如何在保证不去伤害他人的前提下逃离攻击者。同时，被挠痒痒的人会大笑，这也是鼓励挠痒的人继续挠痒，并且更加频繁地做这件事。这也大大增强了这种行为的价值，因为多次以后，人们会更加剧烈地去挠痒痒。

7.Wrinkled Fingers And Toes
7.手指和脚趾在水中起皱

Spending a long time in the water will lead to fingers and toes becoming wrinkled. This bodily function has baffled researchers for decades, with very little evidence to say definitively what the cause of the reaction was. A leading theory had been that water caused the skin to swell, leading to the wrinkling effect.
长时间将手和脚浸泡在水中，会使手指和脚趾变得满是皱纹。这项身体机能困惑了科研者几十年，没有什么决定性的证据能解释产生这种现象的原因。一种前沿理论认为，水使皮肤发生膨胀，从而形成褶皱效果。
Scientists now believe they have come up with the exact reason. According to a number of researchers, the wrinkling is an evolutionary advantage that helps to increase grip in wet conditions. Experiments showed that those with wrinkled fingers and toes get a better grip on wet objects.Another study from Newcastle University theorized that the function might have helped our ancestors handle tools in rainy conditions or have steadier footing on a soaked floor, providing an advantage over others who did not get wrinkly fingers and toes from water.
如今，科学家们认为他们终于找到了准确的原因。根据一批研究者的调查，起皱现象是一种有益的进化结果，它能帮助人体握住表面湿滑的物体。实验表明，起皱的手指和脚趾能更好地服帖在湿滑的物体上。另外，英国纽卡斯尔大学的研究表明，这种机能利于我们的祖先在下雨的时候握紧工具，也能够在湿滑的地面上站得更稳，相比较那些在水中手指和脚趾不会起皱的动物而言，我们明显占有优势。

6.Lump In Your Throat
6.喉咙哽咽

Ever been really sad and felt a lump in your throat even though you knew for a fact that there's nothing physically there? That's a pretty common occurrence that happens to people when they get bad news or are on the verge of crying.
你是否曾有过因非常伤心而喉咙哽咽的情况？即使你知道自己的身体明明没什么问题。对于人们而言，在听到坏消息和几乎要哭出来的时候，这种情况经常发生。
The "lump in the throat" sensation is a consequence of the fight-or-flight response inbuilt in humans, which is induced when a person is put in danger or under intense stress. In these emotional situations, the body pumps blood and oxygen to the brain and muscles to allow it to react faster. This has the added effect of causing the heart to pump harder and for breathing to become more frequent. To facilitate this, vocal chords, known as the "glottis," expand to allow more air to pass through the throat. However, when a person tries to swallow, the glottis need to close. The muscles effectively work against each other, causing the "lump" sensation.
这种"喉咙哽咽"的感觉是人体"战斗或逃跑的反应机制"产生的结果，这种机制使得人在遇到威胁和处于强压的情况下，就需要立即决定战斗或逃跑。在人感到悲伤的情况下，人体会立刻将血液和氧运输到大脑和肌肉，以便我们能迅速反应。这也使得心脏的鼓动更加剧烈，呼吸动作更加频繁。为使这一系列过程顺利进行，发音器官，也称为"声门"，会迅速扩大，让更多的空气进入咽喉。然而，人们吞咽的时候，声门是需要关闭的，所以肌肉会有力地阻止声门的运动，从而形成"哽咽"的感觉。

翻译：李莹 来源：前十网