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万物简史 第425期:生命的起源(19)

But about 3.5 billion years ago something more emphatic became apparent. Wherever the seas were shallow, visible structures began to appear. As they went through their chemical routines, the cyanobacteria became very slightly tacky, and that tackiness trapped microparticles of dust and sand, which became bound together to form slightly weird but solid structures—the stromatolites that were featured in the shallows of the poster on Victoria Bennett's office wall. Stromatolites came in various shapes and sizes. 但是,大约在35亿年前,更加坚强的东西变得显而易见。只要哪里的海水很浅,可见结构就开始展现。在藻青菌完成惯常的化学过程的当儿,它们开始带有点儿黏性。那个黏性粘住了微小的灰尘和沙粒,一起形成了有点古怪而又能坚困的结构——浅水里的叠层石,维多利亚·贝内特办公室墙上挂的画里就是这类东西。叠层石有各种形状、各种大不。 Sometimes they looked like enormous cauliflowers, sometimes like fluffy mattresses (stromatolite comes from the Greek for "mattress"), sometimes they came in the form of columns, rising tens of meters above the surface of the water—sometimes as high as a hundred meters. In all their manifestations, they were a kind of living rock, and they represented the world's first cooperative venture, with some varieties of primitive organism living just at the surface and others living just underneath, each taking advantage of conditions created by the other. The world had its first ecosystem. 叠层石有时候看上去像巨大的花椰菜,有时候又像毛茸茸的地垫(叠层石在希腊语里就是地垫的意思);有时候,叠层石呈圆柱状,戳出水面几十米——偶尔高达100米。从各种表现形式来看,叠层石都是一种有生命的岩石。叠层岩代表了世界上第一个合作项目,有的种类原始生物就生活在表面,有的就生活在下面,一方利用了另一方创造的条件。世界有了第一个生态系统。 For many years, scientists knew about stromatolites from fossil formations, but in 1961 they got a real surprise with the discovery of a community of living stromatolites at Shark Bay on the remote northwest coast of Australia. 多少年来,科学家是从化石结构了解叠加层石的。但是,在1961年,他们在遥远的澳大利亚西北海岸的沙春湾发出了一个有生命的叠层石社会,着实吃了一惊。 来自:VOA英语网 文章地址: http://www.tingvoa.com/html/20180711/572792.html