为什么全人类都在悄悄往左走？科学家至今没有答案

🗞 标题导读

📖 原文与参考译文

Put a small crowd of people in an open space and ask them to walk around, and something odd happens. They do not move as randomly as you might think. Again and again, in experiments in Spain and Japan, groups of pedestrians began drifting counterclockwise, as if an invisible current had started to pull them around the room. The effect was consistent time and time again. In one early set of trials, 32 out of 33 groups showed the same counterclockwise tendency.

"When analyzing the experiments, my colleagues realized by chance that in 32 out of 33 experimental trials, as people moved and turned, they noticeably preferred to turn counterclockwise," said Claudio Feliciani, a project associate professor at the University of Tokyo. "This was completely unexpected as, at least instinctively, when people walk around randomly, you imagine people turn as their needs suit them, with little sign of an overall preference. But there was a definite, measurable tendency for people to turn counterclockwise over clockwise, all things being equal."

The researchers kept narrowing the possibilities. They analyzed children in a Japanese nursery school during a free-running activity. The counterclockwise motion appeared even more strongly there. The children, about 5 years old, often moved in a stable vortex-like pattern, with most of the group circling in the same direction. Young children have had less time to absorb adult conventions about walking routes, sports tracks or public-space etiquette. It does not prove the bias is innate, but it weakens the case that culture alone explains it. The researchers also surveyed 168 people in Spain to see whether an unwritten social rule might exist. The responses did not reveal a clear norm favoring counterclockwise movement. If anything, many respondents expected clockwise motion.

More than 200 people walked alone, one at a time, inside an enclosure. Their paths still showed a counterclockwise bias. This latter result is perhaps the most telling. It suggests the effect does not require a crowd. A crowd can make the pattern easier to see, but the source appears to lie in individual movement. The cause remains unknown. "It likely does not come from the eyes, because we tried to patch people's left or right eyes and the bias was still there," Feliciani said. "And some people asked us if it might be large-scale phenomena like the Coriolis force or Earth's magnetic field, but this seems unlikely given what we have managed to point to so far." The authors suggest that subtle biomechanical or neurological asymmetries may be involved.

📚 核心词汇

🔍 长难句语法拆解

句子一

Young children have had less time to absorb adult conventions about walking routes, sports tracks or public-space etiquette.

1. 现在完成时 have had：表示「截至目前所拥有的时间较少」，与过去时「had less time」相比，强调的是一种持续到现在的状态，而非单次过去事件；
2. 不定式作后置定语 to absorb：修饰 time，表示「用来吸收……的时间」，相当于 time that is spent absorbing；
3. 并列名词短语 walking routes, sports tracks or public-space etiquette：三个短语并列作 conventions 的同位修饰，对应「行走路线惯例、运动跑道惯例、公共场所礼仪惯例」，注意 etiquette 不可数；
4. 隐含逻辑：这句话在说，幼儿逆时针偏向反而更强，是因为他们还没被文化规范「矫正」过——这是一个以「相对剥夺」（less time）作为论据、为「天然倾向」辩护的推理句。

句子二

It suggests the effect does not require a crowd. A crowd can make the pattern easier to see, but the source appears to lie in individual movement.

1. 形式主语 It 指代上文整段实验结果，这是科学写作中极常见的前指（backward reference）结构；
2. 使役动词结构 make + O + adj. = make the pattern easier to see，注意 adj. 后接不定式 to see 构成「形容词 + 不定式」形式，表示「让规律变得更容易被观察到」；
3. appear to do 表示「看起来/似乎」，是学术写作中常用的「限定语气」（hedging language），比直接断言 the source lies in... 多一层不确定性——作者诚实地承认这是推断而非已证之事；
4. lie in 固定短语，意为「根源在于，在于……之中」，注意不要与 lie（说谎）混淆，此处是不规则动词 lie-lay-lain（躺/位于）的第三人称单数现在时形式。

延伸思考： 你现在就可以做个小实验——在一片空地上随意走几圈，看看自己最终是逆时针还是顺时针转了。如果你也向左偏，那你不过是在重复人类几百万年演化写进身体里的某个神秘程序。科学家最诚实的一句话也许是文中 Feliciani 说的那句："This was completely unexpected."——真正好的科学，永远从「意想不到」开始。