A changing planet

Ever since Earth formed roughly 4.5 billion years ago, its climate has gone through a number of incredible changes.
地球形成至今已有约45亿年，在这期间，地球气候经历了诸多令人难以置信的变化。

All you have to do is look at images of the Jurassic Period to know that at one time, much of our planet was covered in extremely hot and humid jungle. Skip ahead a couple million years and you get to an ice age event, when global temperature experienced a huge drop. While many species were not able to deal with these changing climate patterns, others successfully adapted, and some are even still with us today.
你只要看看侏罗纪时期的照片，就会知道曾经地球大部分地区都极其炎热潮湿、丛林密布。向前跳转几百年，你会进入冰河时期，当时全球气温经历了一次骤降。虽然许多物种无法应对这些变化的气候模式，但是有些物种成功适应，甚至存活至今。

Now, as humanity pushes the planet closer to another extreme climate event, scientists are eager to find out how the world’s species will react.
现在，随着人类将地球推向另一个极端性气候事件，科学家们急于发现地球物种将作何反应。

The idea was highlighted in a study published on April 6 in the journal PNAS, which showed that between 1970 and 2010, open water species such as lobsters and fish had declined by about half in tropical marine zones across the globe because over the 40-year time period, sea temperatures in those regions had risen by roughly 0.2 C.
发表在4月6日《美国科学院院报》上的一项研究强调了这一观点。该研究显示，在1970年至2010年间，全球热带海洋地区开放水域中的龙虾、鱼类等物种总数减少近一半，原因是过去40年内，这些地区的海水温度上升了将近0.2摄氏度。

The lower numbers aren’t a sign of all the sea creatures dying off though. In fact, the scientists found some of them outside of their traditional habitats, meaning that if a species can migrate to cooler waters and adapt in a new environment, they will.
不过，数量减少并不代表所有海洋生物都将灭绝。实际上，科学家发现，有些生物离开了原本的栖息地，这意味着如果一些物种可以迁移到较冷的水域，适应新的环境，他们就会这么做。

However, those movements aren’t always a good thing; species that can’t move, such as coral, which is fixed to the seabed, rely on the fish and other sea creatures to contribute to the natural food chain and stay healthy. Additionally, when a non-native species moves into a new area, it threatens to disrupt the ecosystem that already exists there.
然而，这些迁移并不总是一件好事；不能迁移的物种，比如固定在海底的珊瑚虫，依靠鱼类和其他海洋生物，形成天然的食物链，从而健康生存。此外，外来物种迁移至新地方，可能扰乱原本的生态系统。

Depending on the species, it can take anywhere from one generation to thousands and thousands of years to properly adapt, so the changes that have occurred in just the last 40 years are very troubling for scientists. As Sebastian Ferse, an ecologist at the Leibniz Centre for Tropical Marine Research, Germany, explained: “In geological history, this has occurred in the blink (眨眼) of an eye. To see such changes occurring so rapidly is something quite alarming.” He added, “One of the big questions is ‘Will coral reefs as ecosystems and corals as species be able to move north or south fast enough to adjust to a changing climate?’”
对这些物种而言，真正适应新环境可能需要经历一代甚至千万年，所以近40年出现的这些变化令科学家感到十分困扰。正如德国莱布尼茨热带海洋研究所生态学家塞巴斯蒂安·弗泽解释的，“在地质历史中，这发生在眨眼之间。看到如此迅速的变化，真的令人担忧。”他补充道，“其中一个大问题是，‘作为生态系统的珊瑚礁和作为物种的珊瑚能够快速向北或向南迁移以适应变化的气候吗？’”

以上文章内容选自《21世纪学生英文报高中版》，详情请见《21世纪学生英文报高中版》高二828期