万物简史 第262期:大地在移动(16)（在线收听） |
Earth is alone among the rocky planets in having tectonics, and why this should be is a bit of a mystery. It is not simply a matter of size or density—Venus is nearly a twin of Earth in these respects and yet has no tectonic activity. It is thought—though it is really nothing more than a thought一that tectonics is an important part of the planet's organic well-being. As the physicist and writer James Trefil has put it, "It would be hard to believe that the continuous movement of tectonic plates has no effect on the development of life on earth." He suggests that the challenges induced by tectonics—changes in climate, for instance—were an important spur to the development of intelligence. Others believe the driftings of the continents may have produced at least some of the Earth's various extinction events. 在岩质行星中，只有地球才有板块。为什么是这样，这多少是个谜。这不仅是个大小或密度的问题──在这些方面，金星几乎是地球的孪生兄弟，但它没有板块活动。据认为──真的仅仅是认为──板块是地球机体的重要组成部分。正如物理学家兼作家詹姆斯·特雷菲尔所说：“如果说构造板块的移动对地球的生命发展没有影响，这是难以想像的。”他认为，构造地质学引发的挑战──比如气候变化──对知识进步是个重要的促进。还有人认为，大陆漂移至少是地球上某些绝种现象的原因。
古地球版块
In November of 2002, Tony Dickson of Cambridge University in England produced a report, published in the journal Science, strongly suggesting that there may well be a relationship between the history of rocks and the history of life. What Dickson established was that the chemical composition of the world's oceans has altered abruptly and vigorously throughout the past half billion years and that these changes often correlate with important events in biological history—the huge outburst of tiny organisms that created the chalk cliffs of England's south coast, the sudden fashion for shells among marine organisms during the Cambrian period, and so on.
2002年11月，剑桥大学的托尼·迪克森在《科学》杂志上写了一篇报道，强烈认为岩石史和生命史也许有联系。迪克森确认，在过去的50亿年里，世界海洋的化学结构时常突然发生戏剧性的变化；这些变化往往与生物史上的重大事件有关联──比如，大批微生物突然出现，后来形成了英格兰南部海岸的白垩悬壁；寒武纪贝类动物在海洋生物中突然增加；等等。 |
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