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This is Scientific American's 60-second Science, I'm Christopher Intagliata.

这里是科学美国人——60秒科学系列，我是克里斯托弗·因塔格里塔。

Deep in the Amazon lives one of the world's largest freshwater fish: the legendary¹ Arapaima. It tips the scales at hundreds of pounds, making it a coveted² catch for extreme anglers, like Jeremy Wade³ from the show River Monsters.

亚马逊河深处生活着世界上最大的淡水鱼之一：传说中的巨骨舌鱼。它重达数百磅，因此成为了电视节目《河中巨怪》里令杰里米·韦德等极限垂钓者梦寐以求的猎物。

(CLIP: River Monsters audio)

（音频片段：《河中巨怪》音频）

After a dramatically scored struggle, he catches one. It takes two guys to hold it up!

经过激烈斗争，韦德抓住了一只巨骨舌鱼。两个人才能把它抬起来！

(CLIP: "There it is. Look at that for a fish! Look at that massive female Arapaima; about 150 pounds.")

（音频片段：这就是巨骨舌鱼。快看这条鱼有多大！这只巨大的雌性巨骨舌鱼大概有150磅重。）

Speaking of scales, this giant fish has another superlative quality: "It has these very impressive armored scales on its body, which prevent penetration⁴ by predators⁵ teeth yet still makes the fish quite flexible and nimble in the water."

说到鱼鳞，这种巨型鱼还有一个卓越的特质：“它身上有防御性极强的鱼鳞，既可以防止被捕食者的牙齿咬穿，又能确保其在水中灵活敏捷地畅游。”

Robert Ritchie, a materials scientist at U.C. Berkeley. The predators he's talking about are piranhas. But the mighty⁶ Arapaima has them beat with its scales—one of the "toughest flexible biological materials," according to Ritchie's team.

加州大学伯克利分校的材料科学家罗伯特·里奇说到。他所说的捕食者是水虎鱼。但强大的巨骨舌鱼用鱼鳞击败了水虎鱼，据里奇团队介绍，巨骨舌鱼的鱼鳞是“最坚硬且最柔韧的生物材料”之一。

After subjecting the scales to stress tests and electron microscopy in the lab, they figured out the scales' secrets. For one, they have a hard, mineralized layer on the outside.

在实验室对巨骨舌鱼的鳞片进行压力测试和电子显微镜检查后，他们发现了鳞片的秘密。首先，鳞片表面有非常坚硬的矿化层。

"You need the hard layer at the surface to prevent the thing from penetrating⁷. But if the whole scale was made of this hard layer, it would just shatter, like if you tried to penetrate⁸ a piece of glass."

“表层要非常坚硬才能防止被穿透。但如果整个鳞片都由这种硬层构成，那在被刺后就会像玻璃一样破碎。”

And so the scale then has a layer of softer but tougher collagen on the inside—more resistant⁹ to cracking in a piranha's bite. Materials scientists have already figured out this trick—to build materials with a hard layer on the outside and a tough layer on the inside. But the secret of the Arapaima scales is how exquisitely¹⁰ they transition from the hard to the tough.

因此，鱼鳞内部有一层更柔软也更坚韧的胶原蛋白，能更好地抵抗水虎鱼的撕咬。材料科学家已经发现了这种诀窍，能做出外层坚硬内层坚韧的材料。但巨骨舌鱼鳞片的秘密在于它们如何精巧地从坚硬向坚韧过渡。

"We would love to do that in synthetic¹¹ materials; it's just very hard to make materials like that. Maybe 3-D printing in the future can do this. But nature does this rather cleverly because it builds materials from the bottom up, from the atoms and molecules¹² up to the macro scale."

“我们想把合成材料做成这样，但现在很难制造出这样的材料。也许未来的3D打印技术可以做到。大自然非常聪明地做到了这一点，因为其从原子结构到分子结构，再到宏观维度，自下而上地制造材料。”

Photos and details are in the journal Matter.

研究相关的照片和细节发表在《物质》期刊上。

So who cares about a fish's scales? Well, the Air Force Office of Scientific Research does—they funded the study—because Kevlar and other body armors are incredibly heavy. And this piranha-proof fish could be the key to a lighter¹³ load.

那谁会在乎鱼鳞呢？美国空军科学研究办公室就很关心，他们资助了这项研究，因为凯夫拉尔防弹衣和其他盔甲都非常重。而这种不怕水虎鱼撕咬的巨骨舌鱼可能是减轻负重的关键。

Thanks for listening for Scientific American's 60-second Science. I'm Christopher Intagliata.

谢谢大家收听科学美国人——60秒科学。我是克里斯托弗·因塔利亚塔。