经济学人下载: 海洋生物的隐身斗篷 (1)

THE ocean is dark and full of terrors, and the black dragonfish is the darkest of them all.
海洋中充满黑暗与恐惧，黑色的深海龙鱼是其中最黑暗的生物。

Its surface, new measurements reveal, is as black as the blackest material known—the result of an abyssal arms race.
最新测量数据表明其表面和最黑暗的已知物质一样黑—这是深海军备竞赛的结果。

"The trick to being really dark is to control the scattering of light," says Sonke Johnsen of Duke University, in North Carolina, who studies the dragonfish.
“黑暗是为了控制光的散射”，北卡罗来纳州杜克大学研究深海龙鱼的Sonke Johnsen说道。

"You have to let light into a material and let it bounce around a lot."
“需要让光进入某种物质并让光反射出来。”

Black velvet, for instance, appears darker than other fabrics because photons (the particles of light) skip between its fine hairs and do not escape.
比如黑天鹅绒，看上去比其他纤维物质更加黑暗，因为光子（光的微粒）在细绒毛之间跳动且不会逃脱。

Similarly, Vantablack, the least reflective artificial material, traps photons in a forest of carbon nanotubes standing on their ends.
同样，Vantablack这种最不反光的人造材料将末端碳纳米管丛中的光子困住。

It absorbs 99.965% of visible light. Objects coated in it seem to disappear, leaving behind an inky silhouette.
它可以吸收99.965%的可见光。包裹在其表面的物体好像消失了，只留下漆黑的轮廓。

Karen Osborn of the Smithsonian National Museum of Natural History, in Washington, DC,
华盛顿州史密森尼国家自然历史博物馆的凯伦·奥斯本

noticed a similar effect when she tried to photograph deep-sea fish,
发现了一种类似的效果，当时她在拍摄深海鱼，

many of which are coated in a fragile black film that has to be removed before a picture can be taken. Under a scanning electron microscope,
其中很多都鱼都被盖上了一层脆弱的黑膜，在拍摄照片前需要把它拿下来。在扫描电子显微镜下，

she discovered that this film is made of millions of microscopic melanin granules shaped like drug capsules, capped by a thin gelatinous layer.
她发现这层膜是由百万个药物胶囊一样的微观黑素颗粒制成，这些黑色颗粒表面有一层薄薄的凝胶层。

The absorbing effect of the film is so great that instruments calibrated in the usual way cannot detect any light reflected from the fish at all.
薄膜的吸收效果很好，普通的仪器无法探测到鱼反射出的任何光。

Dr Osborn's attempts to measure the light inside an empty pitch black room yielded the same result.
奥斯本博士尝试在一间空旷漆黑的房间中测量光线，但结果也是一样。

Eventually, she and her colleagues worked out that the dragonfish reflects just one in every 2,000 photons incident upon it—an absorbance of 99.95%.
最终，她和她的同事发现深海龙鱼仅反射入射到其表面的1/2000的光—吸光度为99.95%。

Similar measurements hold true for a whole range of fishes brought up from the abyss.
类似测量值也适用于来自深海的各种鱼类。

In the deepest depths of the ocean, what light could these animals be trying to avoid?
在海洋最深处，这些动物是为了躲避什么光呢？

The photic zone, which is bathed in sunlight during the day, and starlight and moonlight at night, reaches down a few hundred metres.
透光层白天沐浴在阳光之中，夜晚沐浴星光和月光，透光层低达几百米。

Yet blacker-than-black fish are found much deeper than that. The black dragonfish, for instance, lives up to 2,000 metres beneath the surface.
但更黑的鱼生活在透光层之下。例如，黑深海龙鱼生活在水面两千米之下。