新研究重新探索斑马条纹背后的奥秘

很长一段时间以来，科学家们一直试图弄明白斑马的身上为什么有条纹，以及这种独特的黑白图案到底是如何帮助它们抵御潜在的掠食者的袭击。早期的博物学家就此提出了 “运动眩晕” 理论，但科学家们发现，动物运动时的保护机制可能另有原因。

It's something that's puzzled biologists for over a century. You might think if you're trying to avoid being hunted down and eaten, that sporting a striking black and white pattern isn't exactly the best way to do it.

这是困扰了生物学家一个多世纪的难题。你可能觉得，如果在试图避免被捕捉并被吞食的命运，那一身醒目的黑白图案可不是最好的办法。

But early naturalists thought otherwise. They put forward the theory of 'motion dazzle', believing that it's hard for predators to estimate the speed or direction of patterned prey while it's running.

但早期的博物学家却不这么认为。他们提出了 “运动眩晕” 理论，认为掠食者很难估计身上有图案的猎物在奔跑时的速度和方向。

And somewhat in the spirit of that, dazzle patterning was used on ships in the First World War to help them evade being spotted. But can this really be the case?

本着这一认识，在第一次世界大战中，令人眩晕的图案被应用于船只上，使其不易被发现，但这样做真的有效吗？

It's counter-instinctive, perhaps. And scientists in Exeter have been taking a much closer look. They've been testing the theory using a touch-screen game called Dazzle Bug. That's where you have to catch a rectangular bug, but it keeps changing its pattern in an effort to stop you doing so. What the scientists found was that even when they were moving, the bugs still tended to lose that clear patterning.

这个理论也许与我们的直觉相反。对此，英国埃克塞特的科学家们进行了更为仔细的研究。他们用一款名为 “眼花虫（Dazzle Bug）” 的触屏游戏来测试 “运动眩晕” 理论。游戏中，玩家需要捕捉一条长方形的虫子，但这条虫子会不断改变它身上的图案，以防被玩家捉到。科学家们发现，即使在移动过程中，这些虫子仍然容易失去醒目的图案。

It's the strongest evidence yet against the 'motion dazzle' hypothesis. And as a consequence, the scientists suggest that protection in motion may rely on a completely different mechanism. Where that leaves the zebra is anyone's guess. But while the results may raise more questions than they answer, it does reinforce the idea that even for scientists, nature is a constantly moving target.

这是迄今为止反驳 “运动眩晕” 假说的最有力证据。因此，科学家们认为，如何在移动的时候保护自己可能依赖于一种完全不同的机制。斑马身上的条纹该如何解释，谁也说不准。尽管研究结果引出的问题可能比它们给出的答案多，但研究确实进一步证实了这样一个观点：即使对科学家来说，大自然也是一个变幻莫测的研究对象。