Across the century and a half since the Challenger expedition, our understanding of life in the depths has offered many surprises.[qh]
自“挑战者”号探险以来的一个半世纪里,我们对深海生命的了解给我们带来了许多惊喜[qh]
。One of the most important of these involves the existence of thriving communities of living things clustered around hydrothermal vents in the ocean floor.[qh]
其中最重要的一点是,海底热液喷口周围存在着繁荣的生物群落[qh]
。These vents form where cracks in the Earth's crust allow seawater to come into contact with liquid magma.[qh]
这些喷口形成于地壳的裂缝,使海水进入喷口与液态岩浆接触[qh]
。At the surface, water exposed to magma would simply boil away, but deep below the surface, the pressure prevents this.[qh]
在地表,暴露在岩浆中的水会简单地蒸发掉,但在地表以下深处,压力阻止了这一情形的发生[qh]
。Instead, the water is expelled back into the ocean in a superheated geyser.[qh]
取而代之的是,水通过一个过热的间歇泉被排放回海洋[qh]
。These jets can exceed 400C, and bear a stream of minerals upwards from the Earth's mantle.[qh]
这些喷流水流的温度可以超过400摄氏度,并携带着一股来自地幔的矿物流[qh]
。As the water cools, these minerals solidify, forming structures that can be dozens of metres high and can grow as much as 30cm a day.[qh]
随着水的冷却,这些矿物质凝固,形成了几十米高的结构,每天可以变高30厘米[qh]
。The first hydrothermal vent was found in 1977 by scientists surveying the seabed 2,500 metres below the ocean on the Galápagos Rift, between Ecuador and the Galápagos Islands, who detected a temperature spike near the ocean floor.[qh]
1977年,科学家在查看厄瓜多尔和加拉帕戈斯群岛之间的加拉帕戈斯裂谷海2500米处的海床发现了第一个热液喷口,他们在海底附近发现了一个温度峰值[qh]
。When the scientists reviewed the photos their submersible had taken, they were amazed to find a thriving community of living creatures.[qh]
当科学家们回看他们的潜水器拍摄的照片时,他们惊讶地发现了一个繁荣的生物群落[qh]
。In an article published soon afterwards, the scientist Robert Ballard marvelled that the photograph taken just seconds before the temperature anomaly showed only barren, fresh-looking lava terrain.[qh]
在随后不久发表的一篇文章中,科学家罗伯特·巴拉德感到惊讶的是,在温度异常发生前几秒钟拍摄的照片只显示了荒芜、看起来清新的熔岩地形[qh]
。But for “13 frames (the length of the anomaly), the lava flow was covered with hundreds of white clams and brown mussel shells.[qh]
但在“13帧”(温度异常的时长),熔岩流被数百只白色蛤蜊和棕色贻贝壳覆盖[qh]
。This dense accumulation, never seen before in the deep sea, quickly appeared through a cloud of misty blue water and then disappeared from view.[qh]
这种密集的堆积,以前从未在深海中见过,迅速出现在云雾般的蓝色海水中,然后从视野中消失了[qh]
。For the remaining 1,500 pictures, the bottom was once again barren of life.”[qh]
在剩下的1500张照片中,海底又一次一片荒芜[qh]
。”Since that first discovery, more than 600 fields of vents have been identified, all teeming with living organisms.[qh]
自第一次发现以来,已经确定了600多个喷口,所有喷口都充满了生物体[qh]
。Specially adapted colonies of mussels and other shellfish cling to their seething columns alongside fields of feathery worms and starfish; crabs and shrimp dart here and there, feeding in the cloudy water.[qh]
特别适应的贻贝群和其他贝类的群落,紧贴着喷口那火热的柱体,旁边是长满羽毛的蠕虫和海星;蟹和虾在浑浊的水中来回游动觅食[qh]
。Such richness of life should be impossible in the darkness of the ocean's depths – without sunlight there is no photosynthesis.[qh]
如此丰富的生命在黑暗的海洋深处是不可能存在的——没有阳光就没有光合作用[qh]
。But the creatures that thrive around the vents do not draw upon the sun's energy.[qh]
但在喷口附近繁荣成长的生物并不依赖太阳的能量[qh]
。Instead, they rely on chemosynthetic microbes capable of transforming the chemicals produced by the vents into energy.[qh]
相反,它们依靠化学合成微生物,将喷口产生的化学物质转化为能量[qh]
。The discovery of animals around hydrothermal vents has led to a dramatic broadening of our understanding of the sorts of environments in which life can survive.[qh]
热液喷口附近动物的发现大大拓宽了我们对生命生存环境的理解[qh]
。This has significant implications for the search for extraterrestrial life – if life thrives in such environments on Earth, it is plausible it might flourish in similar conditions in the oceans of ice moons such as Enceladus, which orbits Saturn.[qh]
这对寻找地外生命有着重要的意义——如果生命在地球上这样的环境中茁壮成长,那么在类似土卫二这样的冰卫星的海洋中,生命也可能在类似的条件下茁壮成长,土卫二围绕土星运行[qh]
。It has also shifted assumptions about where life on Earth began: perhaps it was not in a shallow pool, but somewhere in the depths of the primordial sea.[qh]
它也改变了关于地球生命起源的假设:也许它不是在一个浅水池里,而是在原始海洋深处的某个地方[qh]
。In other words, the deep ocean might not be a place of death and forgetting, but rather the birthplace of life on our planet.[qh]
换句话说,深海可能不是死亡和遗忘的地方,而是我们星球上生命的发源地
。[qh]