在光线不存在的海洋深处,一群带有光吸收皮肤的鱼在黑暗中消失了。一组科学家发现,一些深海鱼的皮肤吸收的比99.95%of the light that hits them, making them appear ultra-black.
杜克大学和史密森尼国家自然历史博物馆的团队现在发现了至少16种超黑鱼类。这些鱼中的每一个都配有专门的皮肤,使他们可以在狩猎或藏在黑暗中逃避检测。
Karen Osborn, the co-author of thenew study, first became interested in the skin of these deepwater fish when she tried to photograph some specimens that had been brought back to the surface. “如何设置相机或照明都没关系 - 他们只是吸了所有的光线。”
She set up a Canon DSLR camera with four strobes then tested various lighting setups by taking lots and lots of photographs. Finally, she adjusted contrast and applied a high-pass filter uniformly across the images, the better to bring out the details.
她补充说:“多年来,我删除了数千种其他鱼的失败镜头,因为我无法在照片中提供细节。”“如何设置相机或照明都没关系 - 他们只是吸了所有的光线。我希望我现在有几个来说明这一点。”
Because sunlight does not reach more than a couple hundred meters beneath the ocean’s surface, most deep-sea creatures make their own light, called bioluminescence. Bioluminescent glows are used to attract mates, distract predators and lure prey.
They can also expose nearby animals–foiling a predator’s stealthy approach or shining a beacon on potential prey–unless those animals have the right camouflage. “If you want to blend in with the infinite blackness of your surroundings, sucking up every photon that hits you is a great way to go,” Osborn said.
超黑鱼的近乎完整的光吸收取决于黑色素,黑色素是染色并保护人皮肤免受阳光的相同色素。奥斯本(Osborn)和她的同事们发现,这种色素不仅在超黑鱼的皮肤中丰富,而且以独特的方式分布。
Pigment-filled cellular compartments called melanosomes are densely packed into pigment cells and these pigment cells are arranged very close to the surface of an ultra-black fish’s skin in a continuous layer. The size, shape and arrangement of the melanosomes cause them to direct any light they do not immediately absorb toward neighboring melanosomes within the cell, which then suck up the remaining light.
“Effectively what they’ve done is make a super-efficient, super-thin light trap,” Osborn said. “Light doesn’t bounce back; light doesn’t go through. It just goes into this layer, and it’s gone.”[EurekaAlert]